Air France Flight 447: A detailed meteorological analysis

NOTE: This writeup is from an acquaintance of mine who wrote some powerful meteorological software, Digital Atmosphere, that I use in my office. He used that software (and others) to analyze the Air France 447 crash from the meteorological perspective.  h/t to Mike Moran – Anthony

by Tim Vasquez

Air France flight 447 (AF447), an Airbus A330 widebody jet, was reported missing in the equatorial Atlantic Ocean in the early morning hours of June 1, 2009. The plane was enroute from Rio de Janeiro (SBGL) to Paris (LFPG). Speculation suggested that the plane may have flown into a thunderstorm. The objective of this study was to isolate the aircraft’s location against high-resolution satellite images from GOES-10 to identify any association with thunderstorm activity. Breakup of a plane at higher altitudes in a thunderstorm is not unprecedented; Northwest Flight 705 in 1963 and more recently Pulkovo Aviation Flight 612 in 2006 are clear examples.

Back in the 1990s I did flight route forecasting for the Air Force. One of my assignments in summer 1994 was forecasting was the sector between Mombasa, Kenya and Cairo, Egypt for C-5 and C-141 aircraft. The Sudan region had tropical MCS activity similar to this with little in the way of sensor data, so this incident holds some special interest for me as one of our C-5s could easily have followed a very similar fate. Using what’s available to me I decided to do a little analysis and see if I could determine anything about the fate of AF447 and maybe through some circuitous, indirect means help give authorities some clues on where to look.

1. Reports and evidence

Reports indicate AF447 reported INTOL (S01 21.7′,W32 49.9′ or -1.362,-32.832) at 0133Z and was to proceed to TASIL (N4 00.3′,W29 59.4′, or +4.005,-29.990) in 50 minutes (a true track of 28.1 deg) (source) indicating that it flew high altitude route UN873 (see below).


Enroute High Altitude Caribbean and South America H-4, 30 AUG 2007 (National Geospatial-Intelligence Agency)

Though the actual flight plan data was not accessible to me, this corresponds well with an actual flight plan found on the Internet for a Varig B767 from Rio de Janeiro to Frankfurt:

(FPL-VRG8744-IS -B763/H-SIRYW/S -SBGL0110 -N0485F290 PCX3 POKA UA314 NUQ/N0475F330 UA314 SVD UZ10 NTL/M080F320 UN873 FEMUR/M080F320 UN873 INTOL/M080F320 UN873 EPODE/N0476F340 UN873 ASEBA/N0475F340 UN873 SAGMA/M080F340 UN873 CVS/M080F360 UN873 LIMAL/N0463F360 UN873 GDV UN858 SUNID/N0454F380 UN858 DGO UN976 PPN/N0457F360 UN976 LATEK UN871 KUDES T163 PSA PSA2W -EDDF1129 LSZH EDDL -EET/SBRE0050 SBAO0309 ORARO0340 GOOO0355 GVSC0518 GCCC0618 GMMM0746 LPPC0836 LECM0848 LFFF0951 LSAS1042 EDUU1059 EDFF1111 RIF/PPN/N0456F390 UN857 BAN BAN2E LEMD RMK/ETOPS UNDER 120 MIN RULE ENROUTE ALTS SBNT GVAC)

I decided to project the flight forward from INTOL. An altitude of FL350 and speed of 520 mph was given. Presumably this is ground speed according to the ACARS specification. Compensating for a 10 kt headwind as given by the SBFN sounding this yields an airspeed of M.80, which correlates well with the A330′s typical early cruise profile. This yields the following aircraft coordinates:

Time Coordinates Description
0133Z -1.362,-32.832 Reported INTOL
0145Z -0.033,-32.125 Extrapolation
0200Z +1.629,-31.242 Extrapolation
0215Z +3.290,-30.357 Extrapolation
0223Z +4.150,-29.876 Estimated TASIL
0230Z +4.951,-29.469 Extrapolation

2. Meteorological analysis

Surface analysis showed the suspected crash region to be within the intertropical convergence zone (ITCZ), which at this time of year is usually found at about the 5-10N parallel. A region of strong trade winds covered most of the tropical North Atlantic and this kept the ITCZ in a somewhat southerly position. The linear convergence along the ITCZ and the unstable atmospheric conditions combined to produce scattered clusters of thunderstorms.


Surface analysis for 0000Z. (NCEP)

Using McIDAS I acquired satellite GOES-10 satellite data from UCAR and centered it over the region between INTOL and TASIL. I then plotted the waypoints using McIDAS’s built-in coordinate entry panel. Since the source satellite images are georeferenced NOAA/GINI datasets, the points shown here are very accurate and are NOT placed by hand but by lat/long coordinates to the nearest 0.001 deg (0.06 mile). In the image below, the stationary southerly point in blue is INTOL and the aircraft’s estimated location from the above table is marked with a cross. Graticule spacing is 5 degrees. For the orange temperature plots I used the NCL/3aw curve; the sharp gradient of the enhancement from dark to light occurs at 243K (-30 deg C), indicating a cloud top of FL310 assuming the satellite pixel is completely overcast with that layer (which is not always true).

NOTE: If you have trouble seeing some of the large images, the source link is here -Anthony

Frame Controls Satellite images
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satellite image

(Hit reload if you don’t see the satellite images in the looper above)

Raw infrared images are also available here: 0145Z, 0200Z, 0215Z, 0230Z.

And finally this image shows a zoomed image at 0215Z when AF447 made its last transmission:

click for a larger image

About 90% of the cloud material seen on this image is actually multiple levels of convective debris fields from dying storms and activity that occurred previously during the day, with only scattered cirrus fields at flight level. The active thunderstorm areas are defined by small-scale mottled areas of cold cloud tops. Compare with this structural diagram below of a similar tropical MCS in the same area in 1977. It illustrates that planes inflight are clear of most dangerous weather throughout a tropical system except when directly above an active updraft area.


Schematic of a typical tropical MCS observed in the Atlantic southwest of Dakar on 4 Sep 1974. (Structure and Dynamics of a Tropical Squall-Line System, R. A. Houze Jr., Mon. Wea. Rev., 105, 1540-1567)

It appears AF447 crossed through three key thunderstorm clusters: a small one around 0151Z, a new rapidly growing one at about 0159Z, and finally a large multicell convective system (MCS) around 0205-0216Z. Temperature trends suggested that the entire system was at peak intensity, developing rapidly around 2300-0100Z and finally dissipating around dawn. From a turbulence perspective, these cold spots would be the areas of highest concern as they signal the location of an active updraft producing new cloud material in the upper troposphere.

The last communication from the plane was at 0214Z (12:14 am local meridian time). This was an automated ACARS message reporting an electrical fault and pressurization problem. This would be about the time the plane was beginning to exit the cluster, but not before having flown for 75 miles of numerous updrafts. The exact aircraft location cannot be determined with certainty, however, since a 1-minute time error in position or reporting time translates to 9 miles of spatial error.

The Fernando de Noronha sounding is available here and shows typical tropical conditions with modest positive energy throughout the column from the surface up to 45,000 ft. There is what looks like anvil level material above 25,000 ft. The significant dry mid-level air is somewhat unusual and suggests the potential for enhanced evaporational cooling in the upper troposphere enhancing downdraft production, and any synoptic-scale lift (if present) enhancing instability through adiabatic cooling of the layer.

I modified this sounding (see below) using the prevailing temperature/dewpoint field across that part of the ocean and modifying for some cooling due to nighttime loss of heating. This is my best guess at the parcel profile that fed this storm. It yields a worst case instability of 1048 J/kg of CAPE, which is moderately strong but considered borderline for typical severe weather. Vertical velocity can be obtained by w=2*CAPE^0.5 yielding a maximum possible updraft speed contribution of 45.8 m/s or 102 mph, though in reality this is usually much less (on the order of half or less) due to precipitation loading and other factors.

3. Conclusions

The satellite imagery indicates that numerous cumulonimbus towers were rising to at least 51,000 ft, and were embedded in extensive stratiform anvils with tops of 35,000 to 45,000 ft. This kind of configuration is actually quite normal for equatorial storms due to the higher tropopause height, but it emphasizes that the aircraft was certainly within the bulk of an extensive cumulonimbus cloud field for a significant amount of time and that storms could indeed have been a contributing factor to the crash.

I’ve edited this section Monday night to cut down on the speculation about the accident chain, especially since I don’t know a whole lot about A330 systems. The airliners.net board and other sites cover the aircraft and CRM systems quite well. What I will try to do, however, is summarize what the aircraft probably encountered based on the data and my own experience.

* Turbulence — Turbulence is a definite candidate as a contributing factor. There is an isolated storm at (1.6,-31.5) that appears suddenly at 0200Z just as the A330 enters the main MCS cluster. From a turbulence perspective it is by far the most dangerous formation found on the loop. However it is 10-25 km to the left of UN873 and it is doubtful the crew would have been deviating at this time. Other cells like this one embedded within the main MCS may have caused severe turbulence. Young updrafts are particularly dangerous to flights because they contain significant rising motion yet precipitation fields have not yet fully developed and airborne radar signatures are weak, reducing the likelihood the crew will deviate around the cell. Another concern is the extensive upper-level dry air shown on the SBFN sounding (not counting the anvil debris at 350-300 mb), which may have contributed to enhanced evaporative cooling in and around the anvil and aggravated the turbulence experienced by the flight, especially around the margins of anvil clouds and towers. It is worth considering that cumulative periods of heavy turbulence crossing through the cluster may have caused minor internal damage that progressed in some way into an emergency.

* Icing — With a flight level temperature of -43 deg C suggested by the proximity sounding the A330 would have been flying mostly in rime ice and possibly some clear ice and graupel. At -43 deg C, water cannot exist even in supercooled form (see here for an explanation). The equivalent potential temperature throughout the profile is absolutely insufficient to bring warmer air with supercooled water to flight level. Without the supercooled water there is very little ice buildup on the airframe. My conclusion is that unless the plane descended below FL300 icing would not be the culprit.

* Lightning — Due to the high cloud tops and freezing level at 16,000 ft, there was extensive precipitation by cold rain process and it is likely the MCS was electrified. Lightning of course being considered with good reason since the A330 is one of the most computerized and automated airliners in service. I will say based on my 25 years of meteorology the storms were almost definitely producing lightning. As far what a strike would do to the A330, I have to leave that to to the avionics experts. Some answers might be found at http://www.airliners.net/aviation-forums/.

* Precipitation — A dual engine flameout due to precipitation or ice ingestion is a noteworthy possibility as has been discussed on other sites (specific to the A330 type too). The precipitable water content in any tropical weather system can run very high. However a rain-induced flameout is not possible because supercooled water cannot exist at the -43C cruise altitude and insufficient equivalent potential temperature exists, even in updraft cores, to bring warmer air beyond a few degrees change to the flight level. Therefore the plane at FL350 was completely within some mixture of rime ice, graupel, or small hail. But again, as the link indicates, even ice poses risks to the engine.

* Hail — I got a few comments about hail. I am not entirely convinced that structural hail damage is a factor, partly because I can’t recall hearing much about large damaging hail at altitude in my experience with equatorial flight operations. This would require strong instability, which I’m not yet sure we have, not only to grow the stones but to loft large hailstones from the embryo “nursery” at FL200-250 up to flight level. A value of 1000 J/kg CAPE is really on the fence but not out of the question. The other problem is the mounting body of evidence (see SPC studies) suggesting well-sheared storms (this profile is poorly sheared) are the ones conducive to structures that support hail growth. Finally, another issue is airborne radars are be highly sensitive to hail because of the very high backscatter values of ice, making evasive action likely, and the “young updrafts” I pointed out earlier as a threat would not have provided the residence times necessary yet to contain hailstones; their main threat would be severe turbulence. I am not sure about the hail hypothesis, but I believe there is a high probability of graupel, small ice pellets, or small hail at FL350 in the storm complex (see Icing above).


Overall what we know for sure is weather was a factor and the flight definitely crossed through a thunderstorm complex. There is a definite correlation of weather with the crash. However the analysis indicates that the weather is not anything particularly exceptional in terms of instability or storm structure. It’s my opinion that tropical storm complexes identical to this one have probably been crossed hundreds of times over the years by other flights without serious incident.

Still, in the main MCS alone, the A330 would have been flying through significant turbulence and thunderstorm activity for about 75 miles (125 km), lasting about 12 minutes of flight time. Of course anything so far is speculation until more evidence comes in, and for all we know the cause of the downing could have been anything from turbulence to coincidental problems like a cargo fire.

My own opinion of the crash cause, as of Monday night, based on the complete lack of a HF radio call and consideration of all of the above, suggests severe turbulence (see the BOAC 911 and BNF 250 tragedies) combining in some unlikely way with CRM/design/maintenance/procedural/other deficiencies to trigger a failure cascade. We can almost certainly count on some unexpected surprises once the CVR is recovered. Until then, all we can do is await the investigation and hope that the world’s flight operations stay safe until AFR447′s lessons are revealed.

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160 Responses to Air France Flight 447: A detailed meteorological analysis

  1. David L. Hagen says:

    Supporting news: Air France Pilot’s Last Communication on Bad Weather

    June 3 (Bloomberg) — Early investigations into the Air France plane crash in the Atlantic Ocean show that there was no evidence of technical problems with the aircraft before takeoff and that the pilot’s last communication was about bad weather.

  2. jon says:

    Look at the seismic activity in area prior to the crash … there was a seismic event on the mid Atlantic Ridge in the early hours of 31 May at position N5° W32° … a bit of a coincidence I guess … more so in that there doesn’t seem to be a lot of seismic activity in this area relative to other faults zones. Could there have been some sort of emission?

    See: http://www.iris.edu/seismon/

    REPLY: There is not any known connection between seismic activity and thunderstorm activity, except that of thunderstorms forming on active volcanic eruptions. Unless there is a new volcano emerging from the sea, the scenario is doubtful. – Anthony

  3. wws says:

    no one dares mention the possibility that a SHHH! (bomb) may have been involved. Wait, who said that? Did I say that? I didn’t say that!

    In spite of the fact that a bomb threat was called in from Buenos Aires just a few days ago, on May 27. Pay no attention to the man behind the curtain saying nasty things like that.

    http://www.sfgate.com/cgi-bin/article.cgi?f=/n/a/2009/06/03/international/i081726D51.DTL

    But don’t worry, that can’t be it. FTA: “A Pentagon official also said there was no indication of terrorism.”

    Other than the fact that a technologically advanced plane catastrophically broke up in midflight and plunged into the ocean for no apparent reason, that is.

  4. CodeTech says:

    As someone who flies extremely often, it is always disturbing to see planes go down, and especially to think that they could break apart at altitude.

    I, for one, feel for the families and friends of those lost, and hope they get the closure they so desperately need.

    Thanks for this fascinating analysis, I certainly hope that eventually we can get a definitive answer to what happened to this flight. Maybe the black boxes will be recovered and contain enough information to clear up the mystery.

  5. David L. Hagen says:

    Further to ice causing flameouts see:
    High Altitude Engine Flame-Outs By Patrick R. Veillette, Ph.D. , Business & Commercial Aviation, July 23, 2007

    In the past, it was thought that high-altitude ice particles — particles, not hail — would harmlessly bounce off wings and engine component surfaces and would not result in any ice buildup, either on the wing or in the engine. Recently it has been discovered that this past assumption may be wrong. Whether this discovery will provide an answer for the Beechjet engine flameouts hasn’t been definitively stated right now. However, the findings by several highly qualified research teams are quite eye-opening and have caused many of the engine manufacturers and FAA certification engineers to reconsider engine certification criteria.One of the significant findings of this research is quite surprising. Several researcher teams have learned that those high-altitude ice particles can accrete on static components inside the engine’s core even where the air temperature is significantly warmer than freezing. This interior form of engine icing can grow to such size that it blocks enough of the airflow through the engine’s core flow and adversely affects the operability. This ice accretion could eventually detach from those internal components and go directly into the high-pressure compressor or combustor, causing potential surge or flameout. Unfortunately, detecting this condition prior to such an event is almost impossible because the particles can enter the engine core without leaving ice accretion on the wing, engine inlet and fan components. So the first indication to the pilot is a significant rollback in engine rpm and sometimes complete flameout. . . .According to “The Ice Particle Threat to Engines in Flight,” a paper presented at the 44th American Institute of Aeronautics and Astronautics “Aerospace Sciences Meeting,” the majority of the uncommanded thrust reductions that occurred to engines of RJs happened near major thunderstorms at altitudes between 28,000 and 31,000 feet. Authored by Jeanne Mason, a senior engineer from the Boeing Commercial Airplane division; J. Walter Strapp, a physical scientist from Environment Canada; and Philip Chow, a senior principal engineer from Honeywell International, the report noted that all of these incidents occurred while in IMC, at thrust levels between 90 and 100 percent and in light to moderate turbulence. . . .In some cases the flight crew was diverting around areas of high reflectivity associated with a large convective storm and in most cases the engine problem began within 30 miles of the area of maximum radar reflectivity, often in the anvil outflow region of a thunderstorm. . . .Under the conditions of less dense air (higher altitudes) and decreased power, ice particles can constitute a greater proportion of the total mass flowing into the engine. Third, at low power the metal temperature in the compression section is lower than at high power, making it more susceptible to ice accretion. . . .
    The incident database includes complex cases of multiple convective cells with perhaps merged anvil regions and cases where there was no high-reflectivity core at flight altitude. All three reports recommend minimizing the time spent in these thunderstorm anvil regions. The authors of the AIAA conference presentation advise following the standard practice of avoiding the regions of high radar reflectivity by at least 20 nm since ice water content typically drops off sharply as a function of distance from the storm center. The AIAA report also recommends flying upwind of a cell to avoid the spreading anvil downstream and to limit exposure to high ice particle content conditions, advice that was just as valid before this “ice particle threat” came to our recent attention.

  6. David Ball says:

    To me, it seems appalling that the plane was not redirected to avoid this storm system. Surely the control towers had an idea what was going on weather-wise in the vicinity of the crash site. I understand that time is money when it comes to the airlines, but the cost here was obviously greater than anyone anticipated. Please, correct me if I am wrong.

    REPLY: There’s no ground based remote reporting weather radar out there, all they have is satellite and synoptic maps. It is the pilot’s responsibility to detect and avoid storms using the plane’s onboard weather radar.- Anthony

  7. Ecotretas says:

    AF 447 was very near to a TAP plane at the time it went down. Pilot from TAP, which was slightly to the west, confirmed on Portuguese TV that it was a “normal trip for that zone, smooth”. In the meantime, brazillians have suggested a link with global warming. There is even a greenie that said he had predicted it more than 2 years ago!

    Ecotretas

  8. jon says:

    One heck of a coincidence though!

  9. adoucette says:

    The disturbing thing to me is that the A330 design is derived from the A300.

    Both have composite tails.

    In the AA-587 crash in Nov of 2001, the NTSB blamed the failure of the A300′s composite tail on the co-pilot.

    The NTSB claimed that the pilot made dramatic rudder inputs to counter wake turbulence from a 747 which had departed Kennedy two minutes earlier.

    See ground tracks I developed for both planes:

    http://usread.com/flight587/AA587-FLIGHT_PAV2-trk4b.jpg

    See Victor Trombetta’s analysis of AA 587′s demise here: http://www.usread.com/flight587/Timeline.html

    The NTSB said that the pilot, to combat mild turbulence, over controlled the aircraft by swinging the rudder fully to one side and then all the way to the other side, and it was this over-control which exceeded the tail’s design limits.

    Pictures of the tail damage are here:

    http://www.ntsb.gov/events/2001/AA587/tailcomp.htm

    Now if this is possible from rudder inputs in mild turbulence in clear air at relatively low airspeed over NY, consider what could happen at high speed in major turbulence over the ITCZ.

    Arthur

  10. jon says:

    Massive underwater eruptions do occur at depth and are known to release considerable amounts of gas … see: http://www.whoi.edu/page.do?pid=7545&tid=282&cid=44586&ct=162

  11. IW says:

    A pilot flying 150 miles behind saw two very bright flashes. The complete and sudden breakup at altitude (leaving a debris field 30+ miles long on the ocean surface) is not consistent with engine failure, or electrical failure, or lightning strike. Weather notwithstanding, an onboard explosion seems most likely to me.

    In some ways, to think it was a terror attack is more comforting; I’d greatly prefer that explanation to suggesting that the aircraft was flawed, or that thunderstorms can bring down aircraft at altitude.

  12. David Ball says:

    I have just read on the net that it may have been a bomb, as the French authorities had received a threat. How much truth there is to this, I do not know.

  13. Steven Kopits says:

    This is truly a remarkable story. A specialist appears from nowhere and gives us a very solid , reasonably technical (but skip to the conclusion, if you like), and accessible presentation on the weather and its likely impact on a disaster only two days old.

    Amazing.

    If you understand why this is truly an impressive feat, then you understand why the New York Times business model is doomed.

  14. dhogaza says:

    no one dares mention the possibility that a SHHH! (bomb) may have been involved. Wait, who said that? Did I say that? I didn’t say that!

    Actually, the possibility has been widely mentioned, but authorities don’t have any reason to jump to that conclusion. We have a very likely candidate for the cause that’s irrefutable. They also have the stream of data from the plane itself describing how it was failing, presumably they’ve not found anything in this to make them suspect a bomb.

  15. Bill Illis says:

    The Atlantic has developed its own mini-El Nino-state right now so convective activity is expected to be strong in the equatorial region.

    http://www.osdpd.noaa.gov/PSB/EPS/SST/data/anomnight.6.1.2009.gif

    http://www.cpc.ncep.noaa.gov/products/people/wwang/rtgsst/rtgsst.gif

  16. layne Blanchard says:

    I flew the following day on AF306, Paris to Seattle. Same model A/C (A330) I’d say the crew and passengers were a bit nervous….but I suspected lightning or turbulence as soon as I heard the story.

    But I’m with CodeTech…. it’s just disturbing. If I’m going to die in a plane, I’d prefer controlled flight into terrain in a cloud…. Not enamored with the cataclismic break up and plunge to sea from altitude scenario.

  17. Rickj says:

    This blog is PURE SPECULATION today. You CANNOT know what happened on that flight, and you state ‘Overall what we know for sure is weather was a factor and the flight definitely crossed through a thunderstorm complex. There is a definite correlation of weather with the crash.’

    Do you have the black box?
    I think not. IF they find the black box and then If your theory is correct, hats off to you. But If they find the black box and they find weather wasn’t a factor, the only weather we’ll be seeing is the wind blowing the egg off your face.
    You list so many factors related to weather but miss out ball lightning. The plane is a Faraday cage, and lightning wouldn’t be a factor, unless I misunderstand physics.

  18. Clarity2009 says:

    I would think if it were just a matter of a flameout, there would have been some kind of radio transmission made because the pilots would have had more time to send a message and they would have wanted to relay their coordinates. This would suggest a violent turbulence event that led to the plane going out of control and/or breaking apart mid-air after which there would be very limited time for the pilots to do anything. Or, of course there is the unfortunate possibility of foul play.

  19. AnonyMoose says:

    I didn’t expect the meteorological inquisition!

  20. Jeff Alberts says:

    The lack of a Mayday or any other radio transmission indicating a problem to me means an immediate catastrophic failure. Either sudden electrical failure which would prevent the radio from working, or something which prevented the pilots from physically making the call.

    A bomb isn’t out of the question, but right now it’s sheer speculation.

  21. Leon Brozyna says:

    Just look at all these strange sounding terms – INTOL … TASIL. At least I was able to find that the distance between the two points was 663 km. For example, “INTOL is an RNAV waypoint located in the Atlantic Ocean, 565 km from Natal, Brazil. The TASIL waypoint is located 1228 kilometers from Natal. TASIL is at the border of the Recife FIR and Dakar Oceanic FIR.” Further details can be found atProjectDisaster. So the bottom line is that all we have so far is speculative but educated guess work; hope they find the black boxes.

  22. AnonyMoose says:

    jon: The estimated location at the last transmission at 0215Z was “+3.290,-30.357″. The quake 00:47:04 UTC at “4.971°N, 32.615°W”
    http://earthquake.usgs.gov/eqcenter/recenteqsww/Quakes/us2009hhab.php

    It was speculated years ago that methane releases could down an airliner, but this has never been observed to happen. Even if the quake released a whole lot of methane (which has been created in a lab in deep crust/mantle conditions), the methane would have had to travel several miles during the 1.5 hours and not been ignited nor dispersed by the thunderstorms. The methane would have to be of large enough volume to mechanically affect the plane (plane would fall in methane, but had 35,000 feet in which to recover), or to affect the airframe. The engines probably did not fail, or the crew would have reported the problem. The plane’s problem was not that the crew was asphyxiated by methane, because the plane would have probably have continued flying.

    I’m ignoring the depth of the seismic event because it’s shallow and I suspect the surface is within the margin of error of the estimate.

    A seismic event can also happen due to volcanic eruption (no other planes had ash damage), landslide (irrelevant), explosion (not reported by other planes, and nuclear surface or airburst would be needed to affect planes at 35,000 feet), or impact event (no meteor fireballs reported by other planes – at 35,000 feet it probably wouldn’t be flaming but something large enough to cause a 4.0 quake should have been visible over the Atlantic when it first hit atmosphere).

  23. Smokey says:

    Rickj (10:22:10) :

    This blog is PURE SPECULATION today.

    I prefer to look at it as a good analysis based on very limited data.

  24. Mike McMillan says:

    Rickj (10:22:10) :
    This blog is PURE SPECULATION today.

    Yup. And?

    You list so many factors related to weather but miss out ball lightning. The plane is a Faraday cage, and lightning wouldn’t be a factor, unless I misunderstand physics.

    Ball lightning has been reported rolling down the aisle of an airliner. Strange stuff. Airliners aren’t complete Faraday cages, as witnessed by all the people talking on their cell phones during taxi-in.

    Airliners can build up tremendous static charges flying through high clouds. I’ve often seen St Elmo’s fire glowing purple off the windshield wipers, and static discharge trees snapping across the windscreen. That might be a concern, as computerized as the Airbus is, and the initial report that automatic maintenance data downlinks concerned sequential electrical system failures.

    Meanwhile, a truly excellent effort looking at the weather circumstances surrounding the flight.

  25. crosspatch says:

    Anthony, must we be presented with Church of Scientology ads (dianetics.org)? I don’t mind commercial ads for products but … well … there it is.

    I think there has been a lot of jumping to conclusions by various news organizations. Generally lightning, for example, won’t bring down a plane but when there are all kinds of stray currents flying around, there could be an electrical arc somewhere that one does want to see one … like in an empty fuel tank or something … if there is a shielding fault.

    The final transmission reporting electrical and pressure problems would be consistent with a catastrophic failure. The amount of turbulence being experienced probably means all of the crew would have been awake or at least not in a deep sleep.

    Rapid decompression at that altitude from something like the loss of a cockpit window would be extremely difficult or possibly impossible to manage but probably wouldn’t generate a simultaneous loss of electric power.

    Loss of both engines would result in problems with electrical power and pressurization but should be manageable.

    I have a couple of questions … on that new cell that they would have hot first, is the position shown in the charts the position the cell was in when the last transmission was received or is that the position of the cell when the flight passed near it? What was the speed and direction of that cell? Could it be that the plane flew directly through it and the position of the cell is moved a bit by the time the flight’s final transmission?

    My bet would be on one of two things:

    1. Cascading structural failure possibly beginning long ago.
    2. Fuel air explosion along the lines of TWA 800 possibly due to anomalous currents induced by lightning strike.

    REPLY: I’ll see if I can get rid of dianetics – Anthony

  26. dhogaza says:

    The plane is a Faraday cage, and lightning wouldn’t be a factor, unless I misunderstand physics.

    Well … if this were true, they wouldn’t spend so much engineering time and money figuring out how to shield sensitive electronics from the effects of lightning strikes.

    From 1963 …

    Elkton, Md. (AP) — Eighty-two persons perished Sunday night in the explosion and flaming crash of a jet airliner near here during a lightning-streaked rainstorm.
    Witnesses said they saw lightning hit the plane, transforming it into a ball of fire. They told of seeing some occupants spilled from the flaming wreckage as it plummeted into a cornfield.
    The plane, a Boeing 707 on Pan American World Airways Flight 214, was minutes away from the end of its 4-hour, 15-minute Puerto Rico-to-Philadelphia run when it bucked into the storm and tragedy struck.

    That one turned out to be due to the strike igniting gasoline fumes inside a fuel cell. Presumably they do a better job of isolating tanks, etc, than they did in this earlier airliner.

    Damage from lightning strikes is normally minor but not infrequent. The cabin interior is insulated from the skin and other metal components, passengers don’t get fried …

    I’ve been in an airliner struck by lightning while descending into PDX. It was … interesting. Big explosion sounds. Bright light from the strike and an orange flaming phenomena outside – dirt on the skin vaporizing? Silence from the cockpit for what seemed like several minutes, presumably as they went through a post-strike checklist to make sure everything was ticking normally. Engines working, everything fine, I wasn’t worried. The woman next to me had never flown before and had been worried from the time we taxied from the gate – did she ever fly again? I’ve wondered. Finally one of the pilots got on the intercom and assured everyone that things were OK, but he couldn’t keep his voice steady. Loud explosion-type noises have their affect even on the professionals, I guess.

  27. Ron de Haan says:

    Thanks for the weather analysis.
    Now let’s wait for the official accident analysis.

    I am sure the officials will go to their limits to find the cause of the accident.

    This will be a most difficult salvation effort due to the location and the equipment needed because the ocean at this location is very deep and covered with undersea mountains.

  28. Anaconda says:

    Yes, it’s speculation, but given the preliminary evidence available (the weather zone), it seems that it is reasonable.

    Not only could lightning and extreme turbulence be a factor, but given the nature of the Tropical Convergence Zone, “extreme lighning” such as “Elves”, Red Sprites”, “Blue Jets” and “Positive Lightning” need to be considered.

    Never heard of these types of lightning?

    Well, that’s okay because only in the last 15 years or so have they been confirmed by Science.

    Pilots of commercial airliners had known of these phenomena for years, but were mostly leary of reporting them for fear that they wouldn’t be taken seriously and it might even impact their careers. (Where have we seen that before?) But early in the 1990s investigators began to take the rumors seriously and to look for evidence of lightning above the clouds.

    Scientists did, indeed, find these rumored “extreme” lightning phenomenon by reviewing old satellite photos.

    The causes for the “extreme lightning” are not well understood, but there are ideas that this lightning is an example of Earth’s weather being connected to larger electrical phenomena ultimately associated with the electromagnetic energy emitted by the Sun and recieved, here, on Earth.

  29. Fernando says:

    Rickj (10:22:10) :

    “This blog is PURE SPECULATION today.”

    Smokey (11:49:28) :

    I prefer to look at it as a good analysis based on very limited data.

    I Love Smokey:

    Speculation:

    I am an A340 First Officer and my airline suffered a serious incident a couple years ago in similar circumstances when encountering severe icing and turbulence at high altitude which led to the sudden loss of all ADIRUs (Air Data/Inertial Reference Units) and to a reconfiguration to alternate fly by wire control law as a result, forcing the crew to declare an inflight emergency and land to the nearest suitable airport. Then it is not difficult for me to make a parrallel with flight AF447′s last ACARS transmissions:
    - 0210: Auto Pilot disconnects
    - 0211,12,13: series of ADIRU and ISIS messages
    - 0213: SEC1 FAULT, PRIM1 FAULT (Alternate Law) with lots of ATA34 (Navigation Systems), ATA22 (Auto Flight), and ATA27 (Flight Controls) messages, and increase of cabin vertical speed. Best regards,
    Alex…..?

    http://www.weathergraphics.com/tim/af447/

  30. Vincent says:

    The concept of a Faraday cage being a a”magical” protection against lighting is flawed in my view. The aircraft frame will probably protect occupants from being killed, but protection of electronic circuitry is far more difficult.

    My experience is in the missile industry, which does not have the more rigourous requirements of the air-industry, so I may be mistaken here. Nevertheless lightning is not trivial.

    This is a new aircraft design. Maybe a flaw in the electrical bonding has been shown up. Who knows?

  31. lex says:

    As a career aviator (albeit military) I read this post with interest, and appreciate the author’s time putting it up.

    One of things I’ve noticed about conjectural discussions about aviation mishaps: It doesn’t matter how well informed the writing, or how persuasive the argument, there is always at least one commenter that shows up and says “Let’s wait for the official analysis.”

    Which makes me wonder, why? This is simply an extended water cooler discussion like you might have at any work place, bar or cafe. In this case we happen to be lucky enough to “work” in the same space as a person with expert knowledge on a plausible causal factor. Not that he’s there, not that he has access to the wreckage – and that’s the whole point, if he was, he’d be obligated to hold fire until the final conclusions had been drawn. But this does provide something to noodle over while waiting the interminable period between finding the DFDR and CVR – if we ever do – and reading the analysis that follows.

    Why do people take it upon themselves to be the town scold on issues like this?

  32. David L. Hagen says:

    Task of Locating Air France Black Boxes Begins

    “We used the atmosphere data in that area to measure the updraft in that area would have been,” Margusity said. “These thunderstorm were towering up to 50,000 feet. And based on that data we saw, we calculate updrafts up to 100 miles (160 km) per hour. … So, we are talking about significant turbulence, significant updrafts that would have really rocked that plane when it hit it.”

  33. wws says:

    to dhogaza:

    “We have a very likely candidate for the cause that’s irrefutable.”

    There’s not one shred of hard evidence that it happened that way at all. Just post event arm-chair spin doctoring.

    There, I refuted it.

    and to AnonyMoose:

    “I didn’t expect the meteorological inquisition!”

    NO ONE EXPECTS THE METEROLOGICAL INQUISITION!!!

  34. Smokey says:

    Faraday cage? click

  35. Anaconda says:

    @ lex:

    Yes, there are always those that want only the “official” version, and don’t want others to offer opinions, whether educated or not.

    These people tend to defend “authority” no matter what the situation.

    Now, there is nothing wrong with “authority” or wanting the “official” version, most times that turns out to be the most informed and expertise.

    But scolding people for offering an opinion and suggesting they “should just pipe down” is unrealistic given human nature.

    And frankly, as we have seen on this website, “authority” is not always right and nor the “official” version a full accounting of the evidence.

    Hopefully, in due course, a full and fair accounting will be made by the relevant authorities and the skys will be safer for the general traveling public.

  36. Mike McMillan says:

    A few notes on decoding the Varig Rio (SBGL) to Frankfurt (EDDF) flight plan -

    The first items are about the aircraft and the nav equipment it has. The -N0485F290 means the flight will climb to 29000 ft altitude and fly at 285 knots true air speed. The UA…, UB…, and UN… are Upper airways, standard routes. Five letter names are waypoints. INTOL/M080F320 means that at INTOL the flight will climb to Flight Level 320 (32000 ft) and fly at Mach .80 . GMMM0746 LPPC0836 … are UTC Greenwich times that the flight will cross into the GMMM and LPPC air traffic control sectors. ETOPS is for “extended twin engine operations” and says the aircraft must remain within 120 minutes of a landing field (with one engine out). ALTS are two alternate airports, SBNT and GVAC.
    Speeds are airspeeds, not ground speed. Air traffic computers have the current winds and compute the ground speeds.

    .
    dhogaza (12:23:24) :
    “Witnesses said they saw lightning hit the plane, transforming it into a ball of fire. They told of seeing some occupants spilled from the flaming wreckage as it plummeted into a cornfield. The plane, a Boeing 707 . . . ”

    That one turned out to be due to the strike igniting gasoline fumes inside a fuel cell.

    Damage from lightning strikes is normally minor but not infrequent. The cabin interior is insulated from the skin and other metal components, passengers don’t get fried …

    Ball of fire, passengers spilling from flaming wreckage plummeting, gotta love it.
    Jet fuel is kerosene, not the explosive gasoline we have in our cars.

    I’ve been hit by lightning (er, rather the plane has) half a dozen times. Big bang, white flash, nothing breaks. You do get small holes punched in the radome or wing tips. And the passenger compartment is Not insulated from the airframe – the metal leg of your seat has a metal to metal connection all the way out to the skin. That’s where the Faraday cage part comes in handy.

  37. MartinGAtkins says:

    Bill Illis (10:10:06) :

    The Atlantic has developed its own mini-El Nino-state right now so convective activity is expected to be strong in the equatorial region

    Tropical Atlantic SSTs are often in phase with El Nino conditions. Plot ENSO along with this data and see if you agree.

    http://www.cpc.ncep.noaa.gov/data/indices/sstoi.atl.indices

  38. Bhanwara says:

    The crash was obviously caused by the spectacular increase in Arctic sea ice.

  39. Fernando says:

    Anaconda (13:25:26) :

    @ lex:

    Yes
    Yes,Yes,Yes….

    Qantas Looking To Blame A330′s Sudden Drop in Altitude On Passengers’ Gadgets?
    Posted by John Mahoney ……. October 10, 2008

    Earlier this week, a Qantas A330 inexplicably climbing 300 feet then nose-diving back down. In the cabin, 71 people were injured. Interestingly, the ATSB is now looking at in-cabin interference from personal electronics as a possible cause of the “irregularity with the aircraft’s elevator control system.” Wait, what? Really?
    This wouldn’t be the first time Qantas has blamed passengers’ gadgets for an in-flight mishap; in July, a Bluetooth mouse was said to have resulted in a Qantas jet’s autopilot being thrown off course. Passengers on Tuesday’s ill-fated altitude drop will now be questioned regarding what electronics they may have been using at the time of the incident.

    http://tinyurl.com/rbc2ow

  40. Sylvia says:

    Fascinating analysis. Thank you.

  41. Houston Aggie says:

    I sure hope the bomb siuation is totally wrong. Anthony great work on the anaylsis. I used to draw the aviation weather map for the entire globe. As a meteorologist and a ceritfied pilot, the speculation about turbulence is the best guess as to what happen up there. Untill black boxes are found, everything is speculation.

    In pilot training, we are taught to deal with turbulence and thunderstorms. An airplane is rated based on how many G’s the plane can take before stucturual damage is caused. Every plane is different based on size and design. The airplane’s wings are the support of the plane in the air, they produce the lift nessecary to fly, it is called load factor. There are several things that can increase the load factor on the wing of a plane. The weight is the main one, but turbulence, quick changes in pitch and roll of the plane, and just simple turning of the plane increase the load factor on the wings. If the load factor, i.e. increased G’s is beyond the limit of design, you can cause stuctural damage to the plane and wings.

    Pilots are taught to avoid thunderstorms all together, but if we happen to fly into a thunderstorms or severe turbulence, we are taught to reduce the plane’s speed to maneuvering speed. If the plane is at or below maneuvering speed, the plane will stall, wings lose there lift or the load factor is greatly reduced, before any damage is cause to the plane. The plane will not just fall out of the sky when it stalls, but will recover when air flow is increased over the wings again producing lift. Usually when a plane is stalled, it will lose 200-500 feet of altitude. I have been in severe turbulence where I heard metal creeking. I reduced the speed and the plane was not damaged, but I only encountered the severe turbulence for a about 10-15 seconds. I can’t image severe turbulence for 10-15 minutes even in a thunderstorm.

    The Air France flight could have experiences 2 or 3 areas of severe turbulence within the thunderstorms where first or second damaged the plane and the third one is what gave the fatal blow, if the pilots did not reduce to maneuvering speed. All of this is speculation, until they find evidence for any of the this or for anything else that brought plane down, I will say speculation and that it is a good theory.

  42. Sam bailey says:

    The bomb Idea has questionable merits, and the quantity explosives needed to remove all ability for onboard warnings or some pilot communication, though not impossible, is unlikely.
    The absence of any emergency call, does imply sudden and catastrophic events.( ball lightning though rare.. would provide a likely causaility.
    The flight recorder should yield some idea.

  43. Antonio San says:

    RickJ, you cannot be more wrong in your assessment!
    The weather analysis provided here is truly top notch information so when french newspapers such as Le Figaro bombasts its readership with the “impenetrable wall of the pot-au-noir” instead of offering the analysis presented here, that is clearly their speculation.
    Congratulation to Tim Vasquez and WUWT to provide the most detailed meteo account of this accident.
    Now at least there is no doubt the plane went through a sever weather zone and given the maps, a zone they could have avoided to the west to the tune of a 400miles detour. End of facts.

  44. Strangely says:

    Excellent investigation of the weather and other factors Tim. However, your initial paragraph about the “clear examples” of modern planes breaking up in thunderstorms is a bit over the top! Even using the two links you provided casts serious doubts about that.
    One was an old 707 variant with first gen turbojets etc that crashed in 63. Hardly modern? The other was the Russian thing that had so many red herrings and inaccuracies surrounding it’s report that it’d need Sherlock Holmes to figure it out. It even says in the report you are quoting that later investigations are pointing to excessive height and a flat spin as the cause.

    I’m not an aviator, but just commenting on the validitity of your opening remarks, that’s all.

    The rest of your investigation is fantastic, by the way. Proper and thorough. I’ll be going through the rest of your website as it looks very interesting. I’ve a layperson’s interest in that sort of thing.

    Thanks.

  45. bimjim says:

    I’m a retired airline pilot, and even though we have our own discussion forum we don’t discuss theories in detail – even amongst ourselves – but we do throw out possibilities to each other based on what hard evidence is known so far.

    The reason we do not discuss crashes in public is because there are professional accident investigators trained to perform investigations based on facts – including data from the “black box” – and follow through with recommendations to the appropriate authorities and manufacturers.

    There is another reason we do not discuss crashes in public… we look at discussions of crashes as leaning experiences, but the public looks at discussions of crashes with sheer unreasoning panic. Anyone who reads some of the above comments and is contemplating a long-distance over-water flight is likely to start calling shipping companies about a berth and asking how long their ship takes to get there.

    Sure, we throw theories around between ourselves under the wing and in conversation, but always seriously and we always see it as something to learn from… some of us do go on to become accident investigators, and we even learn from having a wide range of approaches to any given possibility. That only comes from discussion among our peers.

    My understanding is that this could have been anything – lightning, turbulence, a bomb, whetever. My experience with Americans and Canadians is that they simply refuse to shut up, no matter what drivel they are trotting out without fore-thought, so let’s all take the comments here with a heaping tablespoon of salt and move on with our lives.

    J

  46. K says:

    Tim should be thanked for this information.

    I became acquainted with aerial accident investigation years ago. It was never my primary work or interest. It was before black boxes.

    First, Faraday cages do not provide unlimited protection. But they can provide a great deal. The cage material, its thickness, size of any openings, and the frequency of the electrical fields do matter.

    Fortunately modern airplane design does not conflict with effective cage design. So aircraft cages normally suffice.

    Second, not everything about lightning is known. Therefore protection isn’t absolute.

    Third, the methane idea seems extremely unlikely. Methane emissions can cause grief, but in this case you must have the right methane mixture at the right place and altitude at the right time.

    Fourth. A bomb planted for political purposes would probably detonate shortly after takeoff or before landing. Not much political gain from a mystery far from land.

    A suicide bomber, perhaps a severely depressed person, might donate at any point. And if a bomb was aboard to kill a specific passenger it should be set to donate over the ocean.

    Finally, there is nothing wrong with speculation provided it is presented as speculation. However Investigators and officials should not speculate publicly, it does no good and may make matters worse.

    My guess. Extreme turbulence caused almost instant failure. No time to report.

  47. Dodgy Geezer says:

    and to AnonyMoose:

    “I didn’t expect the meteorological inquisition!”

    NO ONE EXPECTS THE METEROLOGICAL INQUISITION!!!

    wws, what are your three chief weapons…?

  48. Mike Borgelt says:

    Mike McMillan (13:26:22) :

    Don’t forget Mike that, at the time of the Pan Am crash referred to, the US civil airlines were using JP4, wide cut kerosene which had more gasoline like characteristics. This is no longer done because of the increased fire/explosion hazard of that fuel compared to jet A or jet A1 also known as Avtur. There was quite a campaign about this by Flight International IIRC.

    As for the speculation and waiting for the official investigation I’ve seen an official investigation of a gliding accident that went to a lot of trouble to get things utterly wrong because the people doing the investigation made one bad assumption and forget to look at the time averaging characteristics of the recording devices. When I eventually got the raw data this was obvious. Not that the officials wanted to know.

  49. dano says:

    Here’s another look at the weather the flight flew through from the CIMSS Satellite Blog: http://cimss.ssec.wisc.edu/goes/blog/

  50. Ken Hall says:

    Has a plane ever been hit by a meteorite whilst in flight and what would the consequences of such an event? Could it be possible that this is what caused the crash and if so, how would we know?

  51. noaaprogrammer says:

    IW wrote:

    “A pilot flying 150 miles behind saw two very bright flashes. The complete and sudden breakup at altitude (leaving a debris field 30+ miles long on the ocean surface) is not consistent with engine failure, or electrical failure, or lightning strike. Weather notwithstanding, an onboard explosion seems most likely to me.”

    Most terrorists organizations want to claim responsibility for their terrorists acts, as publicizing such events is an effective way of spreading the fear they want certain segments of society to have. Do we know of any such organization(s) claiming responsibility for this crash?

    These very bright flashes and the presence of seismic activity at the same time has caused some speculation of an associated electrical discharge, however Anthony responded by saying:

    “There is not any known connection between seismic activity and thunderstorm activity, except that of thunderstorms forming on active volcanic eruptions.”

    However there are reports of electrical phenomena associated with non-volcanic seismic activity. See:

    Early (1910-1967) references to earthquake lightning: http://www.nature.com/nature/journal/v228/n5273/abs/228759a0.html

    Earthquake light: 1995 Kobe earthquake in Japan: http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V95-4GM45N4-3&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=529eae2596b25421ec1dfb587f3c9d51

    Sumatra-Andaman earthquake of December 26, 2004: http://cat.inist.fr/?aModele=afficheN&cpsidt=17713974

    Speculating that a seismoelectric event caused the crash, how could the blackbox data distinguish between that and regular lightning?

  52. CodeTech says:

    bimjim, I’m glad I don’t fly with you.

    Why? Most pilots I chat with are very forthcoming, and don’t believe it necessary to protect me from myself or my interests. I’m not sure how you intended that post to sound, but it sounded extremely condescending. Insulting, actually.

    We (regulars at WUWT) are hardly uneducated rubes. We understand that every flight contains an element of risk, especially when there is rough weather along our route. Fortunately, “we” also understand that there is probably a higher level of risk every time we drive our car to the local 7-11 than in any flight in a commercial airliner.

    I can’t even imagine why this shouldn’t be discussed. Those who are squeamish or whatever can simply skip it. Most of the commenters here are fascinated by the mechanics of what happened. I know I am… and as my first post at the top stated, I also feel bad for family and friends (but they are in a different zone than this discussion).

    Also, not to bring up a raging debate (elsewhere), I still have white knuckles whenever I find myself flying on those horrid Airbus planes…

  53. Douglas DC says:

    Mike McMillan and others: I second all of the good analysis today, I an ex- professional Pilot myself, everything from Cessna 150′s to DC-7′s . I have flown Night Freight, and for the last ten years of my career, I was an Aerial Firefighter.-I sell Real Estate now.
    I have been hit by lighting in: Piper Navajo,Cessna 402, and DC-7.Scorched paint, bright flash-bang! that was it.However I became a passenger-though flying the Aircraft,due to severe turbulence and Downburst conditions.Most memorable was mashed into the high New Mexican desert in a loaded (fire retardant) DC-7,by a Downburst.It was as close as I ever wanted to come to crashing.It’s a long story, but suffice to say when it happened,it took _ALL_ of our skill to come out alive.It is not good when you have time to think about it…
    FYI -a loaded DC-7 is about 110-112,000 lbs. Gross. We were slapped like a mosquito by that smallish cloud. Flt.447 may have had something else happen,
    but weather can and does crash airplanes…

  54. TP says:

    I usually lurk, trying to learn the science presented on this website. But as a current 747 Captain who has flown the route in question many times in the last few years, I can’t help but respond to several of these comments (in no particular order)
    1) Even with a double flameout or a catastrophic electrical system failure, the A330 in question would have automatically deployed its RAT – Ram Air Turbine – which provides enough power to run essential Flight Control Computers and at least one VHF and one HF radio. The aircraft is also certified to provide battery power for essential systems “for at least 30 minutes”. (so says the reg) Besides, the ACARS still worked, sending an HF data report. This tells me the crew didn’t have time to make a report, not that the radio didn’t work.
    2) AF 447 was operating in a non-radar environment. Anthony mentioned it briefly in a response, but what it means is that ATC is blind, deaf, and dumb – they rely on Position Reports from aircraft, and have no idea what weather is out there. People often assume we have omnipotent radar and communication services spanning the whole globe. The reality is a lot less impressive.
    3) AF447 could have a perfectly functioning WX Radar and still fly through nasty convective activity. A study done by FSF several years ago found that many corporate and air carrier pilots had a poor understanding of the use and limitations of their radar, and used the system in a way that limited the information they received. More importantly, you have to turn the damn thing on. I can’t count how many times I’ve come up to the flight deck to find two knuckleheads flying in an area of known thunderstorms with the radar off.
    4) Someone speculated about AF 447 having a similar tail design to the American A300 which crashed in 2001, due to excessive rudder displacement. The A330 design is similar, but not the same in the most crucial aspect of this conjecture. The lugs which fasten the vertical stabilizer (tail) to the airframe failed on the American A300. They are a different design than that of the A330. In addition, all operators of A300s conducted extensive re-training of their crews after that incident. I find it highly unlikely that the AF crew did the same thing; the A330 is stronger in that respect anyway.
    5) Someone commented about a bomb being the most likely reason for a 14 mile long debris field. Nonsense. Anytime an aircraft breaks up at altitude and traveling Mach .80, its going to leave a long elliptical debris field. The size in question is completely inconclusive; it tells us only that the aircraft didn’t hit the ocean intact.
    My gut feeling is they flew into severe vertical shear, lost cabin pressure and probably destroyed a pressure bulkhead, and very quickly thereafter lost structural integrity. An Air Force C-141 flew into a tropical thunderstorm near Cam Ranh Bay in the early 70s. They gained 20,000+ feet in less than 60 seconds. They managed to limp back to Danang, missing a lot of parts. I am still amazed they lived at all. I fear AF447 met a similar, more severe fate.

  55. Rod Smith says:

    Some anecdotal comments:

    I couldn’t agree more with the folks here who say that lightening strikes on aircraft are not catastrophic. I managed to survive several lightning strikes in B-36′s decades ago. Despite the fact that we carried large quantities of highly volatile 115/145 avgas, we never suffered any fires, although losing the functionality of (roasting) some electronic equipment was not unexpected.

    And I have seen “large fireballs” roll around the compartment, which combined with the explosive sound of the strike will make your knees limber for a few seconds, but turned out to be spectacularly harmless.

    Thunderstorms are a different matter entirely. I remember an old accident report concerning an Air Force plane having baseball size hailstones thrown through the windshield at a distance of two miles from the nearest thunderhead.

    This flight plan analysis is a superb bit of work, but I wouldn’t hazard a guess as to the final cause or causes.

  56. IW says:

    Upon further reflection, it seems that it had to be either an onboard explosion (bomb) or severe turbulence.

    The reason is simple: whatever brought the airplane down had to be able to physically break it up – lightning, hail,etc. have never done this to a modern Western aircraft. The mechanism would be a stretch – like TWA-800, for which investigators speculated, but were never able to actually duplicate what they thought happened (ignition of fuel vapors will not happen with a spark, or even a plausible open flame). Cracking at airplane open is NOT something that happens by hitting it with water or ice, or zapping it.

    There ARE examples of wings being torn off of aircraft at very high G loading (C-130s, C-141s, and others), and highly localised turbulence is what did it to the C-141 aiming for RAF Mildenhall. These are, of course, ridiculously improbable wind shears — but the highly improbable *does* happen (ask any lottery winner). And the weather allowed for these conditions.

    In terms of an onboard explosion: some bombs on aircraft are designed to go off well into the flight. See http://en.wikipedia.org/wiki/Air_India_Flight_182 for one such. As far as I know, no organization claimed credit for it.

  57. David L. Hagen says:

    AP provides more details in:Air France jet likely broke apart above ocean

    . . .The pilot sent a manual signal at 11 p.m. local time saying he was flying through an area of “CBs” — black, electrically charged cumulonimbus clouds that come with violent winds and lightning. Satellite data has shown that towering thunderheads were sending 100 mph (160 kph) updraft winds into the jet’s flight path at the time.

    Ten minutes later, a cascade of problems began: Automatic messages indicate the autopilot had disengaged, a key computer system switched to alternative power, and controls needed to keep the plane stable had been damaged. An alarm sounded indicating the deterioration of flight systems.

    Three minutes after that, more automatic messages reported the failure of systems to monitor air speed, altitude and direction. Control of the main flight computer and wing spoilers failed as well.

    The last automatic message, at 11:14 p.m., signaled loss of cabin pressure and complete electrical failure — catastrophic events in a plane that was likely already plunging toward the ocean.

    “This clearly looks like the story of the airplane coming apart,” the airline industry official told The Associated Press. . . .

  58. David L. Hagen says:

    Further from the AP article:

    One fear — terrorism — was dismissed Wednesday by all three countries involved in the search and recovery effort. France’s defense minister and the Pentagon said there were no signs that terrorism was involved, and Jobim said “that possibility hasn’t even been considered.”

  59. Steptoe Fan says:

    gaining ten or twenty thousand feet in a minute or under would NOT be my choice for an in flight experience.

    those poor souls …

  60. Anaconda says:

    “Extreme” lightning often happens with extreme turbulence.

    I agree, “average” lightning is not likely to cause catastraphic structural failure of a modern commercial jet airliner.

    But taken in combination, “extreme” lightning and extreme turbulence, the two events in rapid and concurrent succession could cause catastraphic structural failure, and as pointed out by thoses more knowledgable, once structural failure has happened at high speed at high altitude, break up of the aircraft is a likely result.

  61. Leon Brozyna says:

    When Colgan Air Flight 3407 crashed outside Buffalo on 12 February, the initial reports quickly focused on icing conditions. And so it went for several days, with more experts chiming in for several days about the dangers of icing as the initial reports seemed to indicate icing problems from the cockpit voice recorders. However, upon more detailed reconstruction, thanks to the information gleaned from the ‘black boxes’, the latest report from the NTSB is that icing was not a serious problem, that the pilot may not have been adequately trained and, when the stick began vibrating to warn of stall conditions, the pilot pulled up, making a bad situation worse. Crew fatigue and cockpit chit chat may have been contributing factors. The problem with Flight 447 is that without data from the black boxes, we may never really know what happened and all we’d be left with is a best guess scenario.

  62. TheAnalyst says:

    Regardless of the actual cause behind the Aircraft break-up and crash, some of the Airbus A300 variants are notoriously unreliable when it comes to electronics. A highly experienced aeronautics expert whom I hold in the highest regard, quite literally told me that the new A380 was a disaster waiting to happen. It truly goes to show how the Boeing Hydraulics/Mechanical based systems are in many forms superior to anything Electronic in nature. Sure, Hydraulics can leak in rare instances, but Electronics, when they fail, can completely trash the entire system.

    The Data Burst Transmission system indicates a major catastrophic failure, and if the failure was brought about due to a manufactured device, then the storm could have been the finishing touch per say. A severely breached cabin would present serious structural issues during normal flight conditions at that altitude, but imagine the chaos which would be brought about in addition due to lightning, high winds, and extreme pressure variances.

    I would normally not jump towards the abhorrent possibility of a malfeasant and purposeful interference in this flight’s operations, but it must be considered, especially given the threat directed at Air France roughly One Week prior. A storm would also provide the perfect cover for such a scenario, so all possibilities must be looked at, both in parallel and combination.

  63. jeez says:

    Can’t….

    resist…

    It’s just weather!

  64. Pat says:

    “Anaconda (12:32:04) :

    Pilots of commercial airliners had known of these phenomena for years, but were mostly leary of reporting them for fear that they wouldn’t be taken seriously and it might even impact their careers. (Where have we seen that before?) But early in the 1990s investigators began to take the rumors seriously and to look for evidence of lightning above the clouds.”

    Similarly during WW2, fighter and bomber pilots/crews also refrained from reporting what they called “Foo Fighters”.

  65. crosspatch says:

    From what I heard, the crash location was some 60 miles South of the Cape Verde Islands somewhere about here.

    It is a very deep part of the Atlantic.

  66. David Ball says:

    Thank you for your information, TP. Much appreciated. I have learned much this day.

  67. rbateman says:

    Something has crossed my mind as I have noticed many planes going down in recent months.
    Is there be a possibility that a GCR strike at critical components of an airplane (such as their computer) could take the pilot’s automated systems out?
    At the planes altitude, perhaps a chance strike is possible, but wouldn’t the upper atmosphere have already caught the ray and broken it up?

  68. Fernando says:

    jeez (17:10:32) :
    Can’t….
    resist…

    many Brahama’s….

    in next year….oh!!! …many Brahama’s….
    overall planning…

  69. Steven Kopits (10:06:49) : “…the New York Times business model is doomed.”

    the New York who?

    dhogaza (10:09:13) : “We have a very likely candidate for the cause that’s irrefutable…”

    Yes, the science is settled.

    Rickj (10:22:10) : “This blog is PURE SPECULATION today…”

    Hey, I missed the SPECULATION FORBIDDEN sign on the way in. When was it posted?

    Jon, Ken: Science calls for exploring all the possibilities, no matter how remote. Well done.

    I still think the fact [confirmed?] that there were two debris fields 60 km apart indicates catastrophic fuselage failure. Order of likelihood: bomb or other antipersonnel device; turbulence; lightning; and, uh, yes, meteorite.

  70. E.M.Smith says:

    The cascade of electrical failures is worrisome. It is possible they were hit with some extreme electrical discharge event. (Why I, perhaps irrationally, prefer the mechanical / hydraulic approach to things… I’ve had to fix too many computerized things when they quit in strange and unexpected ways..)

    Per the tail fin: I have a big problem with a design that breaks apart if you move the rudder to full deflection. The “fix” of “don’t do that” did not inspire confidence… (Yes, you really can “break the tail off” by the simple expedient of moving the rudder to it’s normal full deflection position… so if you learned to fly in any of the thousands of airplanes where that is OK, it isn’t exactly obvious that moving the control surfaces as you normally would to control the plane in an emergency can break the airplane… IMHO, unforgivably bad human factors problem…)

    But what to I know. I’ve flown a hot air balloon and sail planes and did a bit of hands on as a co-pilot in a Cesna, but nothing near what the pros do… they may be used to the idea that using a control can break your plane…

    I’ve noticed that at the top of the solar max we had a couple of years with nearly no accidents, then with this sudden drop of solar output we’ve had a spike of plane crashes (including the FedEx plane that did a touch and go and crash act while trying to land). No idea if it’s a people problem, a random events have patterns problem, or a solar particles can cause what again? problem: But it is a pattern…

    Personally, I’d be a bit cautious about flying a lot for a while. I’d fly if I needed to do it, but if it’s optional, I’d opt out. At least until things stabilize a bit more…

  71. Mike McMillan says:

    I tend to go with TP’s view, vertical shear. My guess is the aircraft would have been in the low 30000′s, where it would be in t-storm turbulence. The pilots didn’t report deviating for weather, so whatever they saw on the radar didn’t look bad enough to hurt them.

    The maintenance reports went from first faults to system failures to loss of cabin pressure, which would come with a breakup. As I understand it the Airbus is completely fly-by-wire, no mechanical controls at all for the pilots, so loss of flight control computers would be disastrous.

    Just don’t know. We’ll have to wait.

  72. AKD says:

    [snip ]

  73. Yes, us slaves in the data mines often joke aboot a stray alpha particle that flipped a crucial bit in our otherwise immaculate data…servers (particularly those running large in-memory cubes and the like) can do the darndest things.

    And as the Svensmark early experiments noted, the GCR’s which do make it to the surface are very high energy, by definition.

    But I’m not flying Airbus A330/340 (the fully FBW jobbies) anytime soon. Or making any more water-cooler jokes about high-energy particles.

  74. AnonyMoose says:

    The list of failure messages which David L. Hagen posted are very informative. I’m sure the experts with the blueprints will find more interesting details.

    Interestingly, it has been noticed that A330 flight control computers have taken unexpected and dangerous actions on other flights.
    http://news.yahoo.com/s/time/20090602/wl_time/08599190242100

    K: A methane bubble is far-fetched and is only an unlikelyhood due to the seismic event. I didn’t suggest ignition of the methane for several reasons, but the lesser density of methane would be irritating for an aircraft. But a large enough volume of methane to bother an airliner would also increase the chance of ignition, and that would be visible to other pilots. It’s real dark, except for the lightning. And I neglected to point out that if the seismic event was caused by an extraterrestrial rock…the impact happened over an hour before the aircraft flew near, and a rock on the ground would have difficulty bothering an aircraft.

  75. AnonyMoose says:

    jorgekafkazar (18:26:09) :
    Steven Kopits (10:06:49) : “…the New York Times business model is doomed.”
    the New York who?

    The guy in New York who models business wear. Apparently he’s having a hard time.

  76. adoucette says:

    E.M.Smith (18:52:53) wrote:

    Per the tail fin: I have a big problem with a design that breaks apart if you move the rudder to full deflection. The “fix” of “don’t do that” did not inspire confidence… (Yes, you really can “break the tail off” by the simple expedient of moving the rudder to it’s normal full deflection position… so if you learned to fly in any of the thousands of airplanes where that is OK, it isn’t exactly obvious that moving the control surfaces as you normally would to control the plane in an emergency can break the airplane… IMHO, unforgivably bad human factors problem…)

    It was iMHO incredibly poor design, one which Airbus didn’t fix:

    Preliminary calculations by Safety Board and Airbus engineers show that large sideloads were likely present on the vertical stabilizer and rudder at the time they separated from the airplane. Calculations and simulations show that, at the time of the separation, the airplane was in an 8° to 10° airplane nose-left sideslip while the rudder was deflected 9.5° to the right. Airbus engineers have determined that this combination of local nose-left sideslip on the vertical stabilizer and right rudder deflection produced air loads on the vertical stabilizer that could exceed the airplane’s design loads. The Board notes that, at the time the vertical stabilizer and
    rudder separated from the airplane, the airplane was flying at 255 knots indicated airspeed (KIAS), which is significantly below the airplane’s design maneuvering speed of 273 KIAS.

    The rudder control system was also problematical:

    at 250 knots, when the limiter restricts rudder travel to about +/-9.3°, a pilot force of about 32 pounds is required to move the rudder pedals about 1.3 inches. The rudder system on the A300-600 uses a breakout force of about 22 pounds. Thus, at 250 knots, the rudder can reach full available travel (9.3°) with a pedal force of only 10 pounds over the breakout force.

    See NTSB Recommendation.

    As noted previously, pilots were trained after this crash to not do the above, but there are limits to training and maybe the composite tail was strengthened on the 330, but then the forces are much more severe at high speed and extreme turbulence.

    I’m not saying this is what caused it, but then it wouldn’t be like this was the first time that a structural failure brought down an Airbus in the last decade either and it does appear that the plane broke up in flight and the only two things likely to cause that is an explosion or structural failure.

    Arthur

  77. rbateman says:

    E.M.Smith (18:52:53) :
    I’ve noticed that at the top of the solar max we had a couple of years with nearly no accidents, then with this sudden drop of solar output we’ve had a spike of plane crashes
    But it is a pattern…

    You noticed it too. Glad it’s not just me.
    I didn’t know there are no mechanical controls on Airbus.
    Not much hope of flying one if the computer goes down.
    I’m going with the GCR’s as suspect, and I’m NOT getting on an airplane until they settle back down.

  78. Power Grab says:

    @rbateman: Check out the June 2 page for spaceweather.com. Look at the bright night photo from Poland on May 31 at 20:48 UT. They said it was a meteroid, but it was totally unexpected and no one identified a projectile. This AF break-up was in the wee hours of June 1. We finally have a significant sunspot extant. I wish the EM nature of the sun/universe were fully on the table. There might be a connection. We could learn a lot.

  79. Noelene says:

    If it is true that the automated message said that the entire electrical system had failed,what could have caused it?I don’t believe weather alone could cause that.Could the pilot do something wrong that would cause such a failure?I am guessing that the pilot or co-pilot(there is talk that the pilot was on a break)reacted the wrong way to a situation,but in that Qantas incident the pilot temporarily lost control because a malfunction in the computer caused the plane to nose dive.I am worried that there is a problem with the software in the computers of these planes,they can’t ground them all because of the cost,but I wouldn’t travel in one.

  80. K says:

    anonymoose:

    I discounted methane only because it is so unlikely. I certainly don’t doubt that flying into enough methane would produce some odd and undesirable event.

    To my limited imagination that event would either be explosion or loss of lift.

    Explosion requires the right mixture. Up there any methane bubble would be very cold and the pressure very low. It don’t think an external explosion would occur; a real engineer may calculate and find I am wrong.

    Inside the plane it is warmer and the pressure is higher. Methane inside would be far worse.

    Nor am I sure how much loss of lift would occur. Again, how much has the methane mixed with the air. But LOL would give the pilots time to radio. And control might well be regained anyway. Neither happened.

    Satellites were used during the Cold War to monitor the Earth for covert atomic tests. A sizeable explosion at night at altitude would be detectable if the detectors still operate. But that night there was a lot of lightning, not every flash is an explosion.

    For now we can only offer somewhat intelligent guesses. At least I hope we can.

  81. TP says:

    For E.M. Smith and Adoucette –
    Part 23 certified aircraft (read here – airliners) are not required to withstand full stop-to-stop rudder displacement. Boeing does not – cannot – guarantee that a 777 could withstand such a maneuver. Nor does Airbus. Most of us in the industry (myself included) didn’t fully understand this at the time. Its not written intuitively in the regs. The A300 vertical stab lugs WERE designed poorly, but that was just icing on the cake. The American crew exceeded the DESIGN limitations of the aircraft, no differently than if they performed such a flight control input in a 777 or 747, etc.
    The gotcha to the American crash was that AA produced a training manual written by Airbus which taught a full stop-to-stop maneuver during alternate gear extension (trying to get the landing gear to extend when it doesn’t want to). Therefore, Airbus was actually teaching – and thereby sanctioning – operators to perform a maneuver for which the aircraft was expressly not engineered or tested for. OOPS!
    As for GCRs destroying 3 separate Flight Control Computers – its a horse guys, not a zebra. I would sooner bet money on a bad line of code or a nasty thunderstorm. Personally, the Airbus FBW system scares the S*** out of me.

  82. TP says:

    TheAnalyst-
    The A330/340 are a completely new design, not a derivative of the A300. Different engineering. Also, the A300 is an old school mechanically controlled aircraft. The A330 is Fly By Wire.

  83. Keith Minto says:

    What intrigues me is the that the French authorities are saying “there is no hope of finding the black box”. Why so gloomy, they haven’t even started looking!

    dano (14:46:57),that was an interesting ,if data hungry link that you provided. I was surprised at this……” thunderstorm updrafts have been known to initiate strong gravity waves aloft that have generated moderate to severe turbulence.”

    Gravity waves ? Really ? Is the search finally over ?

  84. crosspatch says:

    “A methane bubble is far-fetched and is only an unlikelyhood due to the seismic event.”

    Methane bubble? You HAVE to be kidding me, right? That plane was six and a half miles up. That would have to be one HUGE methane bubble.

    “As I understand it the Airbus is completely fly-by-wire, no mechanical controls at all for the pilots, so loss of flight control computers would be disastrous.”

    Mechanical systems are known to have serious flaws too. That L-1011 that crashed in to Sioux City (United 232) being an example. One engine failure took out three hydraulic systems.

    The beauty of “fly by wire” is that if you think of the aircraft as a giant printed circuit board, you can have a myriad of redundant paths. As long as a server gets a signal, it will act, no matter which path the signal took.

    In many ways fly-by-wire can be much safer than hydraulic or mechanical controls. You can forget about mechanical controls on a plane that large flying that fast anyway. You would have to be a serious jock to move a control surface against that kind of wind.

    Hydraulic systems have one or more pumps (generator), reservoir (battery), lines (wires), and a hydraulic motor that operates the control surface or gear or whatever. If you cut a hydraulic line (short circuit) you have to go to a backup system. With an electrical system you can blow a breaker to conserve what is left of power. Multiple redundant paths are possible with electrical systems. And while it might normally be controlled by a major high-tech computer, there can also be a final emergency mode that is basically an analog servo system. You move a control, it changes a voltage that moves a control surface. I believe I would rather fly a well-designed fly-by-wire system than a mechanical or hydraulic system.

    You can design in a dozen different electrical paths. You can have it all using pretty much digital communications like a computer network and if a path fails, traffic between the controller and controlled is taken from a different path. And if that system fails, you can fall back on an analog dc system that is basically changing potentiometers that change analog voltages that correspond to control positions and the servos act accordingly.

    The more I read about this accident the more it looks like a cascading structural problem. The seeds for such a failure could have been sown in an earlier flight or hard landing. If I were Air France and the black boxes are not retrieved, I would bit the bullet and take two aircraft out of service with similar age and flight history and perform destructive testing on them. Shake them apart and see what falls off first.

    If they don’t get those boxes and there is another failure of this sort on the same airframe, it is going to be a major hit on their business.

  85. Lindsay H. says:

    For someone in New Zealand every flight is a long distance flight, every second flight ive been on we seem to be diverting around weather of one sort or another. I dont know what the flight rules are for Air France out of South America giving the pilot discretion to divert around bad weather. But I know both Quantas which I usually fly and Air NZ give pilots a lot of latitude and use of GPS to route around turbulence, their weather radar and satelite feeds assist in choosing the best route. That freedom for the pilot can cost extra fuel etc, some airlines are a lot more cost consious, and discourage actions which increase operational costs.
    It appears that the airframe broke up at some altitude, with the loss of electric power early in the event, suggests major structural failure regardless of the cause. The fly by wire design of the Airbus series saved a bucket of money in the manufacturing process, but has introduced the risk of complete loss of control, add to that some design limitations in the airframe, plus the european (especially french) willingness to sweep problems under the carpet; this crash might force Airbus to be a little more honest about the integrity of the Airframe design.
    Great Post though; the range and quality of opinion in the comments makes WUWT one of the must read sites.

  86. Dodgy Geezer says:

    A very similar series of events seems to have happened to BOAC Flight 911 in 1966. This 707 flew past Mount Fuji, and was torn apart by turbulence from winds of only 60-70kt. See http://en.wikipedia.org/wiki/BOAC_Flight_911

    This accident was well witnessed from the ground. The turbulence tore off the vertical stabiliser first, followed by the rest of the tailplane and the engines. The remainder of the aircraft spun in, disintegrating as it fell. The 707 left a debris trail 10 miles long, including spraying fuel over a wide area. This matches the reports of the demise of flight 447 closely.

    This also suggests that vertical stabilisers take the brunt of turbulence-related stress, and may fail in any aircraft design. I don’t think there is any need to look for alternative and more obscure causes for the crash..

    …Yes, us slaves in the data mines often joke aboot a stray alpha particle that flipped a crucial bit in our otherwise immaculate data… Wayne Findley

    A long time ago I was working in a virus lab, and had a rig where the entire system memory was being monitored for changes as we ran suspected malicious software. On one occasion a researcher reported ( and had the printout to prove it) a single bit change in a 4Mb memory pack which was completely uncommanded. So it happened, at least once, but we never found out if it was a hardware glitch, a cosmic ray, a monitoring artifact…..

  87. King of Cool says:

    Also a very old and not so bold ex-commercial pilot.

    I can recall being in a Cb in a DC3 going up at 4000 ft /min with both throttles at idle.

    Thunderstorms are monsters that you treat with the utmost of respect and some of my old buddies that flew with QANTAS tell me that they have diverted up to 200 nm to avoid them.

    At this stage there will be a lot of conjecture and we will only know the facts if and when the black boxes are found. But some of the wreckage will certainly give a clue as to a bomb or structural failure.

    There was a QANTAS Airbus incident recently that some-one referred to earlier involving passenger electronics. The incident was actually a faulty air data inertial reference unit which supplies information such as air speed, altitude and position and led the aircraft’s Flight Control Primary Computers to incorrectly determine the airliner was climbing when actually in level flight. As a result, the aircraft’s nose pitched down losing thousands of feet, critically endangering the aircraft and injuring many passengers. I understand this was also crew and procedures related as there had earlier been a warning light on the autopilot.

    I am sure that our investigation team will be closely looking at this incident as aircraft accidents are often a chain events and history has a habit of repeating itself. Commiserations to Air France and all involved and for the sake of world aviation safety good luck with the investigation.

  88. GeoS says:

    Strange that the computer controlling the gear shift (6 gears) in my car went pear shaped about that time. Had to go back to the dealer to be reprogrammed.

    I guess car systems don’t need complicated voting systems to protect against random IC failures. It’s likely CRs present a risk with satellite systems.

  89. Alan Chappell says:

    Spending my working life in the clouds, I have not, and never will set foot on a ‘airbus’ product, it is a accident waiting to happen ! Pieces are made all over Europe and are not a product, but a political wet dream, wings in one country, tail in another, electronics and engines all come from different countries and if you are lucky, get assembled in order, it has been common knowledge that these aircraft suffer from chronic electronic and political problems, not one would ever fly if it was not for hundreds of billions of taxpayers money, expect some real interesting lawsuits in the near future.

  90. Bill Abbott says:

    I think Pierre Sparaco got it right on Monday when he pointed out that airplane disasters, like most complex system failures, are not typically caused by a single event. It won’t be much of a surprise if this was a sequence of failures, faults, errors, etc. A design flaw, bad weather, human error, an unforseen sequence of failure… Even when something breaks, there isn’t

    The China Airlines 747 the broke-up in flight experienced catastrophic failure of of a 20 year old repair. Which was done incorrectly, and never detected by inspections which are created specifically to find problems of that nature.

    The Lufthansa A320 that overshot the runway when landing, killing the cockpit crew and some of the 1st class passengers, overshot because the thrust reversers never deployed, because software was looking for a switch closure indicating weight on the main gear legs, because the wind reversed to a strong tailwind and the plane had been coming in faster than it should have, so it wouldn’t stop flying.

    In one case we’d all say “Bad repair/skin patch”, in the second is clearly a software design/requirements issue. But it really wasn’t just the one thing, it was a chain of events, including something high profile so I can drink a Coke from time to time.

    Cheers!
    Bill IV

  91. jon says:

    AnonyMoose … the seismic event occurred on Sunday, May 31, 2009 at 00:47:04Z … the aircraft disappeared at approximately 02:20Z on June 1 (23:20 local on May 31 in Brazil).

    Gas emissions from volcanoes are primarily water vapour, carbon dioxide and sulphur products … if there was an emission could it have created severe thunderstorms in the area? Just speculation but worth checking out.

    Cheers,

    Jon

  92. Calvin says:

    Great Blog! But with no means to cause offence do you think you can change your profile image? it is blurry and is kind of off putting everytime it comes up as the number 1 hawt post… if not i totally understand.. its been a long day

  93. David L. Hagen says:

    Further clues:
    Air France Flight 447 ‘may have stalled at 35,000ft’ Times Online June 4, 2009

    Airbus is to send advice on flying in storms to operators of its A330 jets, Le Monde reported today. It would remind crews of the need to maintain adequate thrust from the engines and the correct attitude, or angle of flight, when entering heavy turbulence. . . .The fact that the manufacturer of the aircraft is issuing new advice indicates that investigators have evidence that the aircraft slowed down too much, causing a high-altitude aerodynamic stall. This would explain why the aircraft apparently broke up at altitude over the Atlantic. . . .Jean Serrat, a retired airline pilot, told Agence-France Presse: “If the BEA [accident investigation bureau] is making a recommendation so early, it is because they know very well what happened. If they know what happened, they have a duty to make a recommendation, for safety reasons … The first thing you do when you fly into turbulence is to reduce speed to counter its effects. If you reduce speed too much you stall.” . . .the first anomaly was the disconnection of the automatic pilot and computerised flight controls. This means that the pilots were hand-flying the aircraft. . . .French experts dismissed [the no explosion] theory, noting that an explosion could fracture the fuselage and cause the break-up of an aircraft without igniting the fuel, which is mainly carried in the wings.

  94. adoucette says:

    An onborad explosion has to remain a concern:

    The pilot of a Spanish airliner flying near where the Airbus is believed to have gone down reported seeing a bright flash of white light that plunged to the ocean, said Angel del Rio, spokesman for the Spanish airline Air Comet.

    “Suddenly, off in the distance, we observed a strong and bright flash of white light that took a downward and vertical trajectory and vanished in six seconds,” the pilot wrote in his report, del Rio told the AP.

    Arthur

  95. Joe says:

    To Mr. Alan Cambell: You might as well not step into a Boeing product either because they too use parts from all over the world. Seattle or Witchita or Long Beach are just assembly points.

    Also, I used to monitor HF Transoceanic frequencies quite often. To deviate around thunderstorms using HF and the procedures required seems always to take forever (probably 10 minutes) from the time of request to checking with Gander, Shanwick, Santa Maria, Dakar and then to not being able to hear the transmissions clearly so everything needed to be repeated. Quite different from when overland where radar is tracking.
    I stopped monitoring these frequencies because I thought by now we had gone to GPS and satellite transmissions. How wrong I was!

  96. Pete says:

    What about the Kenya Airways (a new 737- 800)flight out of Douala (last year) which crashed 30 secs after take off. There was deinitely a severe thunderstorm involved here. The black boxes were apparently found. What were the findings?

  97. Imran says:

    To anyone who has had the misfortune to experience severe turbulence whilst inside a jet airliner, it seems of little comfort that turbulence should not be able to bring down an aeroplane. I experienced this in December 2000 whilst flying a Continental 777 from Houston to London – somewhere over Arkansas or Tennessee. It was horrific- people screaming, everything flying around. I remember getting dripped on afterwards – the drinks had hit the ceiling ! It seemed incredible that the plane was designed to withstand such treatment … and we didn’t even have anyone injured ! Sometime flights end up with hospitalisations of 30-40 people – how bad must that be ?

    http://www.chron.com/CDA/archives/archive.mpl?id=2003_3678096

    Once you have expereinced the total violence of such turbulence, no amount of scientific assurance will convince you the ‘planes are designed for it’. Personaly I think the Air France tragedy is the result of such a scenario.

    Of coures with global warming making storms worse, we can all expect this to happen more often.

  98. adoucette says:

    Bill Abbott (04:15:29) wrote :

    The China Airlines 747 the broke-up in flight experienced catastrophic failure of of a 20 year old repair. Which was done incorrectly, and never detected by inspections which are created specifically to find problems of that nature.

    The Lufthansa A320 that overshot the runway when landing, killing the cockpit crew and some of the 1st class passengers, overshot because the thrust reversers never deployed, because software was looking for a switch closure indicating weight on the main gear legs, because the wind reversed to a strong tailwind and the plane had been coming in faster than it should have, so it wouldn’t stop flying.

    I believe you were referring to the JAL – 123 flght.
    The improperly repaired rear bulkhead failed, which caused an explosive decompression, loss of the vertical stabilizer and severed all 4 of the hydraulic lines. The plane flew about 30 minutes, using variable trust on the engines to steer the plane (much like the United DC-10 crash at Sioux City)

    http://en.wikipedia.org/wiki/Japan_Airlines_Flight_123
    http://en.wikipedia.org/wiki/United_Airlines_Flight_232

    As to the A320 crash, this sounds almost identical to the crash of a Piedmont 737 at Charlotte, and was caused by a hot landing, and then the inability of the pilot to deploy the thrust reversers because the “squat switch” didn’t engage because the plane was travelling too fast. (In this case the pilot had also set the spoilers to automatically deploy, but their deployment was also based on the squat switch being triggered, so they didn’t automatically deploy.)

    http://aviation-safety.net/database/record.php?id=19861025-0

    Arthur

  99. konamicrew says:

    any news about survivors?

  100. adoucette says:

    Imran wrote:

    “no amount of scientific assurance will convince you the ‘planes are designed for it’.”

    Maybe this will help:

    This is the destructive test of a 777 wing, note that 100% is the design limit load, meaning the highest load the wing is expected to reach in flight, even in severe turbulance. The wing survives more than 150% of this load.

    Arthur

  101. adoucette says:

    Pete (07:33:07) wrote:

    What about the Kenya Airways (a new 737- 800)flight out of Douala (last year) which crashed 30 secs after take off. There was deinitely a severe thunderstorm involved here. The black boxes were apparently found. What were the findings?

    Actually the crash was 2 years ago.
    Canada is handling the investigation on the request of Kenya.
    AFAIK the final results of the investigation have not been released yet.

    http://en.wikipedia.org/wiki/Kenya_Airways_Flight_KQ_507

    Arthur

  102. ralph ellis says:

    As one in the industry:

    In general, lightening will not effect aircraft operations. I have been struck five times without any effect whatsoever. The widely reported Delta airline ‘strike’ was actually a fire.
    http://www.flightglobal.com/blogs/unusual-attitude/2009/04/atlantic-southeast-airlines-cr.html

    .

    Hail, however, is a different matter. Normally aircraft will stay clear using radar, but if you have a radar failure for some reason, the results can be dramatic.
    http://lh3.ggpht.com/abramsv/R48vQ0KUpNI/AAAAAAAAELk/AnqKnEk3NHo/ndi_hailstorm.jpg
    http://rv8.ch/gallery/d/5288-2/111_1104.jpg
    http://news.bbc.co.uk/1/hi/england/manchester/2941118.stm

    Structural failure in a large cell is always a possibility but again this begs the question as to why the aircraft would ever get into that situation in the first place.

    .

  103. Sandy says:

    Say they flew into a big area of 5,000 fpm + lift. The auto-pilot would throttle back the engines and put the nose down to maintain height, this combined with the Stoke’s effect would give an alarming increase in airspeed. The pilots clock this, switch off the auto and pull back to stabilize the speed before they run up the engines. If at that point the plane flew from updraught to 5000 fpm + of downdraught then the total change of angle of attack to highly negative would completely stall the wing and maybe the engines as well.

  104. AnonyMoose says:

    Satellites were used during the Cold War to monitor the Earth for covert atomic tests. A sizeable explosion at night at altitude would be detectable if the detectors still operate.

    The published descriptions are that the satellites watch for a nuclear bomb’s characteristic double-flash. X-Rays escaping from the bomb cause the atmosphere to flash while the fireball is still inside the bomb casing. A few milliseconds later the fireball becomes visible. Normal explosions aren’t noticed. We can conjecture that some lightning causes false alarms, but the engineers probably tried to minimize that.

    adoucette: My favorite destructive test device is one which measures the forces needed to crush a mine jack. It breaks something designed to hold up a mountain.

  105. RobP says:

    Facinating discussion up above of load factors and I now understand why pilots slow down giong into turbulence, which then may give credence to the stall warning issued by Airbus. It seems like balancing air speed is a lot more critical than just arriving on schedule. (A comment I read somewhere – might have been here – talked of the “coffin shoulder” between too slow to fly and too high for the structural integrity od the aircraft.)

    I guess we all think that with GPS, weather radar, electonic auto-pilots, fly-by-wire etc. the skill of the pilot is reduced to a minor factor. Events like this, and the landing on the Hudon earlier this year, are reminders that airline pilots still have a major role in flight safety.

    As a regular long-haul traveller, to think that weather alone can still cause a catastrophic structural failure in modern jet aircraft is worrying. I guess this is why there are so many people trying to find some kind of other circumstances to explain this, if only to give us confidence that we can prevent it happening in the future. I’ve never thought this way about terrorism – maybe that’s the point, it is easier to see the response to these in enhanced security measures etc. (which probably do no more than reassure me – but they have worked in that respect).

    At the end of the day (or in my case, tomorrow morning), we have to get “back on the horse” so to speak and remember that there are very very few plane crashes – a testament to the safety record of Boeing, Airbus et. al. and the airlines that operate them.

  106. ralph ellis says:

    >>Spending my working life in the clouds, I have not, and
    >>never will set foot on a ‘airbus’ product, it is a accident
    >>waiting to happen ! Pieces are made all over Europe and
    >>are not a product, but a political wet dream, wings in one
    >>country, tail in another, electronics and engines all come
    >>from different countries and if you are lucky

    What utter (American presumably) rot. If that is the case, I presume you will never even touch a Boeing with a barge-pole, because their latest airplanes are thrown together from bits made all over the WORLD – not just a ‘United States of Europe’.

    Boeing 787:
    Tail Italy Alenia
    Fuselage Italy Alenia
    Fuselage USA Vought Aero
    Fuselage USA Spirit Aero
    Floors India Tata
    Wings Japan Fuji
    Wings Japan Mitsubishi
    Center wing Japan Kawasaki
    Landing gear France-UK Messier Dowty (with Russian castings)
    Doors France Latecoere
    Flaps Australia
    Engines UK Rolls
    Brakes France Snecma
    etc: etc:

    http://www.aerospace-technology.com/features/feature1690/
    http://en.wikipedia.org/wiki/Boeing_787

    I think, with the 787, Boeing in Seattle might make the go-faster stripes.

    .

  107. ralph ellis says:

    >>Spending my working life in the clouds, I have not,
    >>and never will set foot on a ‘airbus’ product, it is a
    >>accident waiting to happen ! Pieces are made all over
    >>Europe and are not a product, but a political wet dream,
    >>wings in one country, tail in another, electronics and
    >>engines all come from different countries

    What (American presumably) rot. If that is the case, then I presume you would not touch Boeing’s latest offerings with a barge-pole, as they are manufactured from parts from all over the WORLD – not just a ‘United States of Europe’.

    Boeing 787:
    Tail Italy Alenia
    Fuselage Italy Alenia
    Fuselage USA Vaught Aero
    Fuselage USA Spirit Aero
    Floor India Tata
    Wings Japan Fuji
    Wings Japan Mitsubishi
    Wing center Japan Kawasaki
    Nose USA Spirit Aero
    Doors France Latecoere
    Landing gear France-UK Messier-Dowty (with castings from Russia)
    Flaps Australia Boeing
    Brakes France Snecma
    Engines UK Rolls

    http://www.dcvelocity.com/news/?article_id=1750
    http://en.wikipedia.org/wiki/Boeing_787

    With the 787, I think that Boeing in Seattle may make the go-faster stripes…

    .

  108. TP says:

    Arthur –
    FAA and JAA (european) regulations require manufacturers to destructive test a new wing design to 150%. The original A380 wing failed at 140 something percent and required a redesign. Every airliner that has broken up in flight and was designed after the late 1950s passed the 150% test….

  109. adoucette says:

    TP,
    Since the crashes of the Lockheed Electra – (Flt 542 on 9-29-1959 and Flt 710 on 3-17-1960) I can’t recall a single crash caused by structural failure of the wing (in this case actually lack of stiffness in the engine nacelle mounted to the wing was the root cause).
    Once fixed the plane went on for many more years, including the Navy variant, the Submarine hunter – P3 Orion.
    http://en.wikipedia.org/wiki/P-3_Orion
    Arthur

  110. Jeff Alberts says:

    I’ve noticed that at the top of the solar max we had a couple of years with nearly no accidents, then with this sudden drop of solar output we’ve had a spike of plane crashes (including the FedEx plane that did a touch and go and crash act while trying to land). No idea if it’s a people problem, a random events have patterns problem, or a solar particles can cause what again? problem: But it is a pattern…

    Really? A spike? What constitutes a spike? 3 out of 10,000 flights?

  111. Jeff Alberts says:

    To anyone who has had the misfortune to experience severe turbulence whilst inside a jet airliner, it seems of little comfort that turbulence should not be able to bring down an aeroplane. I experienced this in December 2000 whilst flying a Continental 777 from Houston to London – somewhere over Arkansas or Tennessee. It was horrific- people screaming, everything flying around. I remember getting dripped on afterwards – the drinks had hit the ceiling ! It seemed incredible that the plane was designed to withstand such treatment … and we didn’t even have anyone injured ! Sometime flights end up with hospitalisations of 30-40 people – how bad must that be ?

    And it still amazes me how people completely disregard the “fasten seat belt” sign during flight, and the verbal instructions to keep seat belts fastened when in flight and seated (while the sign is off), and until the aircraft has come to a complete stop at the jetway. So many idiots think it doesn’t apply to them, for some bizarre reason. They’re the ones who’s bodies will become projectiles and injure the people who follow very sensible instructions.

  112. adoucette says:

    Jeff,

    3 out of 10,000?

    Hardly,

    There are ~28,000 flights each day in the US alone.

    http://www.natca.org/mediacenter/bythenumbers.msp

    Arthur

  113. Jeff Alberts says:

    adoucette (10:30:00) :

    TP,
    Since the crashes of the Lockheed Electra – (Flt 542 on 9-29-1959 and Flt 710 on 3-17-1960) I can’t recall a single crash caused by structural failure of the wing (in this case actually lack of stiffness in the engine nacelle mounted to the wing was the root cause).
    Once fixed the plane went on for many more years, including the Navy variant, the Submarine hunter – P3 Orion.

    So far none have landed on my house, only 3 miles from the NAS Whidbey runways ;)

  114. David L. Hagen says:

    Brazilian Navy Recovers First Pieces of Downed Air France Plane Bloomberg, June 4, 2009 14:00 EDT

    . . .Some of the plane’s exterior sensors had frozen, French Energy Minister Jean-Louis Borloo said on France’s RMC radio . . .

  115. crosspatch says:

    I think this article in the Times of London could be on the right track. If the pilot slowed down in the turbulence and the wind suddenly changed when he crossed over or through a cell top from a head wind to a tail wind, he could have experienced a high altitude stall. It would be something like wind shear from a downburst in reverse. You have a column of rising air that then spreads out when it reaches some altitude … outflow at the top. You would have a headwind going into it and a tailwind coming out. If they were experiencing severe turbulence, slowing down is the normal course. If you suddenly get a 100mph tail wind when you aren’t expecting one and aren’t going fast enough, you are out of control.

  116. Fred Schloss says:

    The skin made of a composite embedded with relatively thin wire mesh or thin wires can never be as effective against lightning as a continuous aluminum skin.
    Positive lightning current may reach 300 kA and they last longer than negative lightning.

  117. TP says:

    Arthur –
    Somewhat off my last post, but an old A model C-130 used for firefighting crashed at low level after catastrophic wingbox failure in 2003….or was it 2004? Of course, the C-130 was designed for the Air Force, and therefore did not adhere to Part 23 cert. requirements. But it was an inflight wing failure…

  118. Outstanding meteorological analysis, as to the rest of the speculation, it is just that: Speculation. It has its place. If it was a bomb, which I seriously doubt, explosive residue will be present on the fragments.

  119. adoucette says:

    TP
    Yeah, you can’t compare military craft to civilian craft and you really can’t compare OLD military craft to modern civilian craft.

    Now as far as stressful use of an aircraft I doubt anything but dogfighting comes close to fire-fighting.

    The C-130 tanker that crashed in Walker California was the second C-130 to shed its wings doing low level high g pullouts while trying to suppress forest fires (let them burn is my motto)

    The Walker C-130A was built in 1957 and had 21,863 hours on the airframe when the wing failed.

    The wing box on the C-130A uses an alloy of aluminum 7075-T6 that unfotunately is susceptable to fatigue cracks. Lockheed changed the alloy on the C-130E models to 7075-T7531, an alloy which has much better fatigue tolerance and also redesigned the wing box to reduce loads near the point where the wing and the fuselage meet.

    Arthur

  120. adoucette says:

    Christopher wrote:

    Speculation. It has its place. If it was a bomb, which I seriously doubt, explosive residue will be present on the fragments.

    Considering the water its not that likely any residue will remain, but conclusive pitting from the explosive could be found. Still, this would only be on structures very near an explosion, and considering its location its highly unlikely that much of the airframe will be recovered.

    Consider that the explosive that brought down the Pan Am 747 over Lockerbie was in a luggage container and only created a 20 inch hole in the fuselage.

    Arthur

  121. Doug Barber says:

    adoucette, I loved that link to video of a Boeing wing loading test.

    The conclusion in the article atop these comments that extraordinary weather was *a factor* in this catastrophe seems like a safe bet to me. Was it a primary, secondary, or tertiary factor? The author makes no claim in that regard.

    This is my first encounter with wattsupwiththat. Fantastic site, amazing commenters. Thanks to all.

  122. They now say in the radio news that the wreckage found at sea was not from AF447…

  123. crosspatch says:

    So it is increasingly looking like speed of the aircraft was a factor. Either a sensor was giving incorrect input to the on-board systems causing improper flight operation or the pilots made a mistake.

    That the incident happened as the plane was leaving the area of heavy weather. This is an area where one might expect to pick up a tailwind from the storm outflow.

    More information may come to light if they can collect the boxes but so far there is “chatter” that the automatic data being reported from the plane showed “unintelligible” speed data, the plane appears to have been flying too slowly, and the rest of the data reported by satellite is consistent with a “high altitude stall” which may have been nearly impossible to recover from in heavy weather.

  124. ancyta says:

    Hi
    Thank You for your article…it is really sad and i pray for their family.

    Ancy

  125. peter says:

    The most important point is to find out why there is no radio frequency tracking device on this aeroplane.These days tracking devices are very common even if
    Car is lost or stolen can be tracked within seconds.Blackbox is the last hope
    Of the scientific explanations of what actually happened but it is pathetic to know that there is no tracking device installed on the black box.
    Lighting or sudden electric failure due to any reason is THE REAL CAUSE OF THIS ACCIDENT.

  126. Hugo M says:

    IW (09:54:14) : A pilot flying 150 miles behind saw two very bright flashes

    Said pilot was from Air Comet, observing bright lights (not exactly flashes) from 49° W and 7°N. Whatever he saw (probably a meteor breaking up into peaces) was about 2000 km away from the location where AF447 vanished.

    http://www.correiobraziliense.com.br/html/sessao_18/2009/06/04/noticia_interna/id_sessao=18&id_noticia=115913/noticia_interna.shtml?

  127. Layman says:

    What about this?

    Red sprites and blue jets.

    1) Could those events have been present then? then…
    2) Was the plane in the range? then…
    3) What would happen if the red or blue hit the plane?

  128. Jan S says:

    adoucette,
    re: crashes due to structural wing failure: in 1981 a Fokker F28 crashed in the Netherlands after flying into a tornado (http://www.aviacrash.nl/paginas/eindhoven.htm and http://en.wikipedia.org/wiki/NLM_Cityhopper_Flight_431) I seem to remember being told during my study aeronautical engineering that the registered load at the time of right wing breakoff was at 2.28 times the maximum operating load, meaning the safety factor j was in practice 2.28, well above the required safety factor j=1.50

  129. IW says:

    The high altitude stall theory is interesting, but seems to be incomplete. Is there any suggestion that a high altitude stall would actually lead to a breakup of the aicraft at a high altitude?

    I wonder if there was a combination here… the computers may not have been programmed to anticipate the stall recovery techniques, and so they could have prevented the pilots from recovering (Airbuses can do that). That would be quite the double-whammy.

  130. adoucette says:

    Carsten Arnholm, Norway (23:49:03) wrote :

    They now say in the radio news that the wreckage found at sea was not from AF447…

    Not exactly, a helo picked up a wooden pallet they found in the area, but the plane carried no wooden pallets, so the only piece recovered so far wasn’t from AF 447, but the other pieces, including the fuel slick that were spotted from the air (but not retrieved), were from AF 447.

    Arthur

  131. adoucette says:

    peter (02:24:52) wrote:

    it is pathetic to know that there is no tracking device installed on the black box.

    Actually the Flight Data Recorder has an attached Underwater Locator Beacon that will transmit a signal for about 30 days.

    http://en.wikipedia.org/wiki/Underwater_locator_beacon

    The transmitter isn’t that powerful (of necessity, since its battery powered) and thus finding it, even with it broadcasting its location, may still prove difficult if the box is under several miles of water, in mountainous terrain and only its general location is known.

    Arthur

  132. Has anyone thought of a meteorite? Odds are one in a squillion … but one day? Or last week.

  133. i am just a journalist but the eschanges above shed more light on this situation than anything i have read in the general press.in my blog entry http://unsilentgeneration.com/2009/06/03/air-france-447-structural-flaws/, i quote from the New Scientist and Canadian Safety board about structural problems and the use of composites.The Canadians focused on the tail in a cuba-canada airbus flight crash.

  134. ralph ellis says:

    >>Of the scientific explanations of what actually
    >>happened but it is pathetic to know that there is
    >>no tracking device installed on the black box.

    All black boxes have an underwater pinger. But that may be no use if the box has been damaged or is sitting under 2 miles of water. What is the depth there?

  135. David L. Hagen says:

    Nuclear sub to join hunt for jet BBC 15:38 GMT, Friday, 5 June 2009 16:38 UK

    Airbus has reissued guidelines to pilots after experts said the plane may have had false speed measurements.

    A spokesman for Airbus said that a notice had been sent reminding Airbus air crews worldwide what to do when speed indicators give conflicting read-outs. . . .
    Spokesman Justin Dubon said that the inconsistent readings meant that “the air speed of the aircraft was unclear”.

    He said that in such circumstances, flight crews should maintain thrust and pitch and – if necessary – level off the plane and start troubleshooting procedures as detailed in operating manuals. . . .

    The BBC’s Tom Symonds says erratic speed readings could have been caused by heavy turbulence and might have caused the plane’s automatic throttle to power up or down as it passed through heavy storms.

    Meteorologists say that the Air France Flight 447 had entered an unusual storm with 100mph (160km/h) updrafts that sucked water up from the ocean.

    As the moisture reached the plane’s high altitude it quickly froze in -40C temperatures. The updrafts would also have created dangerous turbulence, they say.

  136. idlex says:

    Times: 5 June French Ministers voiced frustration after the Brazilian forces said they had been mistaken in identifying flotsam collected from the ocean as coming from the Airbus A330 that disappeared in a storm on Monday on a flight from Rio to Paris. They also said that they had mis-identified a fuel slick on the surface.

    Can a large jet airliner come down in the ocean and leave no trace whatsoever? If it broke up in flight, there would have been a scattering of floating debris over a wide area. If it dived into the sea, it would have broken up on impact, leaving a local debris field. Only if it successfully ditched on the sea, and sank shortly thereafter, would there have been no trace – except the passengers would have climbed out before it sank.

    It makes no sense, except if AF447 was nowhere near its planned flight path, and the search is being conducted in the wrong place. Perhaps the captain changed course to try to avoid thunderstorms? Perhaps the plane was badly damaged, and the captain was heading back towards land? It seems clear that AF447 wasn’t where it was supposed to be.

  137. TP says:

    Boeing and Airbus publish checklists for “flight with unreliable airspeed or attitude indication”. In my airplane (747-400) it is a memory-item checklist; we’re required to memorize it and be able to accomplish it w/o reference to the checklist. AIrbus re-issued the checklist as a CYA. Boeing would have done the same thing.
    The media questions surrounding pitot tube icing seem flaky. All jets are required to have independent pitot-tube heat for both pitot systems. More importantly, an ice-blocked pitot tube will not change the indicated airspeed if altitude is not changed. My understanding is that AF447 had not changed flight levels prior to entering CBs. Therefore, the ADIRUs would have thought there was no change in indicated airspeed, not an overspeed as speculated.

  138. Hey Skipper says:

    I am an active MD-11 pilot.

    Meteorologists say that the Air France Flight 447 had entered an unusual storm with 100mph (160km/h) updrafts that sucked water up from the ocean.

    Interestingly, given AFR447′s weight and the air temperature at altitude, and very strong updrafts, it is possible for a plane to be going too fast (exceeding max mach) and too slow (below buffet onset speed) at the same time.

    That could have caused the conflicting speed readings.

    Also, the AFR447 undoubtedly had the latest Future Air Navigation System equipment on board. However, I don’t know if the air traffic services unit serving that airspace had the corresponding ground equipment.

    I have written a longer pilot’s eye view of this, but posted it elsewhere to avoid inflicting a word wall on WUWT.

  139. peter says:

    What astonishes me that an aeroplane built with high technology worth
    Billions of dollars and all the sophisticated gadgets and gizmos and
    YET NO TRACKING CAN BE DONE NEITHER FOR THE PLANE NOR FOR THE BLACK
    BOX????????
    Only insurances claims worth HUNDREDS OF MILLIONS of dollars to be paid other than PRECIOUS LOSS
    OF LIVES??
    How does it make sense when a CAMERA AT MARS & MOON CAN SEND PICTURES
    BUT NOT A DROWNED AEROPLANE???

  140. Gerald Machnee says:

    In 2007 there was an incident where two paragliders got sucked into a thunderstorm. One survived. The other was found over 40 miles from where he started.
    See:
    http://www.cbsnews.com/stories/2007/02/16/world/main2486010.shtml

  141. David L. Hagen says:

    Tim Vasquez
    Excellent informative post.
    A possible minor refinement is to check the latest speed information. cf

    The Airbus A330-200 was cruising normally at 35,000 feet (10,670 meters) and 522 mph (840 kph) just before it disappeared nearly four hours into the flight.

    Pilots Saw ‘Fire on Ocean’ Where Jet VanishedFox June 2, 2009

  142. David L. Hagen says:

    TP
    While pitot tubes may be heated, it appears that some models can fail:

    The investigation is increasingly focused on whether external instruments may have iced over, confusing speed sensors and leading computers to set the plane’s speed too fast or slow — a potentially deadly mistake in severe turbulence.

    Pitot tubes, protruding from the wing or fuselage of a plane, feed airspeed sensors and are heated to prevent icing. A blocked or malfunctioning Pitot tube could cause an airspeed sensor to work incorrectly and cause the computer controlling the plane to accelerate or decelerate in a potentially dangerous fashion.

    Air France has already replaced the Pitots on another Airbus model, the 320, after its pilots reported similar problems with the instrument, according to an Air France air safety report filed by pilots in January and obtained by The Associated Press.

    The report followed an incident in which an Air France flight from Tokyo to Paris reported problems with its airspeed indicators similar to those believed to have been encountered by Flight 447. In that case, the Pitot tubes were found to have been blocked by ice.

    “Following similar problems frequently encountered on the A320 fleet, preventative actions have already been decided and applied,” the safety report says. The Pitots on all Air France’s A320s were retrofitted with new Pitots “less susceptible to these weather conditions.”

    The same report says Air France decided to increase the inspection frequency for its A330 and A340 jets’ Pitot tubes, but that it had been waiting for a recommendation from Airbus before installing new Pitots.

    Recovery of bodies may refine crash location:

    RECIFE, Brazil (AP) — A Brazilian military official says searchers found two male bodies in the Atlantic Ocean near the area where an Air France jet is believed to have crashed. . . .They were picked up roughly 400 miles (640 kilometers) northeast of the Fernando de Noronha islands off Brazil’s northern coast.

    Brazil: 2 bodies found near jet crash siteAP June 6, 2009

  143. Mike McMillan says:

    idlex (12:02:47) :
    . . . Can a large jet airliner come down in the ocean and leave no trace whatsoever?

    No. There’s flotsam out there, but even knowing the approximate area, the ocean is big. Very big. Most metal bits would sink, so that limits search aircraft radar ability, and few ships were in the area. That’s changing. They just haven’t found it yet.

    French weather service says IR satellite shows T-storms, but not of unusual intensity. BBC says the aircraft sent 28 automatic maintenance fault reports before it went down.

    Ken Hall (14:51:58) ‘s idea of a meteorite strike is ridiculous. But it does fit. A hit on the right part of the plane would produce all the symptoms we’ve heard of, just as much as a missile strike would. During a pre-dawn turning climbout back in my AF days, I saw one shoot straight down two or three miles away, so it’s not impossible. Only finding kryptonite traces in the wreckage could confirm something that unlikely, though.

  144. Phil. says:

    peter (00:27:13) :
    What astonishes me that an aeroplane built with high technology worth
    Billions of dollars and all the sophisticated gadgets and gizmos and
    YET NO TRACKING CAN BE DONE NEITHER FOR THE PLANE NOR FOR THE BLACK
    BOX????????
    Only insurances claims worth HUNDREDS OF MILLIONS of dollars to be paid other than PRECIOUS LOSS
    OF LIVES??
    How does it make sense when a CAMERA AT MARS & MOON CAN SEND PICTURES
    BUT NOT A DROWNED AEROPLANE???

    Radio waves don’t propagate through water (particularly sea water) if the crash had been on land the EPIRB would have been detected by satellite (406 MHz).

  145. peter says:

    What my point is that there must be PROPER TRACKING of allthe aeroplanes.
    At least the Route taken by aeroplane and LAST POINT OF CONTACT should
    Be mapped with Satellite charting.
    Now a days Satellite can read car licence plate BUT IT IS FOOLISH TO SEE
    HOW COME AN AEROPLANE LOADED WITH 228 PASSENGERS GONE MISSING
    AND DAYS AND DAYS PASSED WITHOUT ANY TRACE >>??

  146. Sandy says:

    If a ship goes down beaconed life-boats pop off and automatically inflate. Surely aircraft have similar systems??

  147. Keith Minto says:

    Sandy (13:59:11) :

    “If a ship goes down beaconed life-boats pop off and automatically inflate. Surely aircraft have similar systems??”

    Aircraft frequently fly over water and, sometimes land in water (Hudson River landing).
    It puzzles me why aircraft parts,wings especially but also tailplane structures and the lower section of fuselage bodies are not built with foam inserts so that they float.
    I realise that it would take up room but would stop aircraft from sinking to the bottom of wherever it did its watery landing. A larger break-up would yield many floating parts.

  148. David L. Hagen says:

    RPT-Timeline of Airbus speed data problems Reuters June 7, 2009

    . . .Air France notices temporary loss of airspeed data lasting several minutes during cruise on A330/340 jets due to icing.

    Air France presses Airbus for a solution. According to the airline, Airbus says using the same sensors recommended for the smaller A320 would not solve the problems witnessed at cruise height and reiterates established operating procedures. . . .
    Q1 2009

  149. IW says:

    So now it looks like the plane did NOT break up at altitude at all. A high altitude stall seems to have been what happened, and then a combination of pilot error and misprogramming of the “computer-knows-best” Airbus systems could have foiled stall recovery (no programmer can anticipate all possible combinations). Also wouldn’t surprise me at all if the pilots decided not to trust *any* of their instruments, and in white-out conditions, flew the bird all the way down. Lots of planes go down in white-out conditions when the pilot decides the instruments are lying to him.

    And voila. Airplane in the drink. It breaks up on or near the surface.

    I *really* hope they find the black box. My money is that the fault is on BOTH the pilot and the computer.

  150. Hugo M. says:

    I found one thing really disgusting: beginning with the very first day, when no one could know for sure what really had happened to the plane, the press (the French gouvernment) started to assert that the Airbus had crashed and there would be no hope for survivors. Then they underlined that probably the remains of the aircraft would never be found, because the ocean would be so wide. Then we were told, since the oceans would be so deep, it would be almost impossible to locate the flight recorders, and even if these devices could found, they could probably never be retrieved — draping the story with photographs of deformed black boxes, while concealing that they are constructed double-walled in order to absorb mechanical shocks, as well conceiling that they are equipped with sonar beacons reaching about 6 km. Then, just two days after the accident, they decided to held a religious ceremony in Notre Dame de Paris to mourn the victims – some of them still swimming in the 28° Centigrade warm tropical sea, possibly themselves still praying for help. That made me angry to the extreme. It would have been the damn duty of at least Germany and France to immediately send all available SAR planes to that region before the last survivor died from pulmonary edema. But the Brazil forces were alone for almost a week – and they still almost are. Now each and every new article suggests the public, that probably the beacons and the recorders would have separated from each other. There is something amiss.

  151. Is there anything that comes to mind by looking at initial photos of the tail?

  152. adoucette says:

    The tail looks similar to the photos of the composite tail from the AA587 crash (see my previous post).
    The fact that the tail looks mostly intact makes me suspect, that like AA587, that the tail most likely failed at the attachment points.

    http://www-tc.pbs.org/newshour/bb/transportation/587crash/splash_image.jpg

    Arthur

  153. David L. Hagen says:

    Crews find vertical stabilizer in Air France crash AP June 8, 2009

    William Waldock, who teaches air crash investigation at Embry-Riddle Aeronautical University in Prescott, Arizona, . . .Waldock — who examined the photos and video of the stabilizer and rudder — said the damage he saw looks like a lateral fracture.

    “That would reinforce the idea that the plane broke up in flight,” he said. “If it hits intact, everything shatters in tiny pieces.”

  154. David L. Hagen says:

    Air France to Replace Airspeed Sensors
    By NICOLA CLARK, NYT June 9, 2009

    PARIS — Air France, facing pressure from some of its pilots after the crash of one of its airliners last week, has decided to immediately replace airspeed sensors on all of its A330 and A340 jets, union representatives said Tuesday. . . .

  155. Heinz Rust says:

    i don’t have a comment but a question.
    can anybody tell me what are the prevailing winds on UN873, FL 300 between cape verde and natal in september
    thanks
    h

  156. the news now is that a paris lawyer named sophie battai has entered the scene as a plaintiff’s attorney in the investigation representing families and seeking information about records pertaining to the plane’s safety.does anyone know anything about her or this situation?

  157. David L. Hagen says:

    IDs of Air France victims could prove jet broke up By MARCO SIBAJA and ALAN CLENDENNING et al. AP, Townhall.com Thursday, June 11, 2009

    One of the messages showed a change of cabin pressure equal to an altitude change of more than 1,800 feet (548 meters) per minute, said Airbus spokesman Stefan Schaffrath.

  158. David L. Hagen says:

    Crash jet ‘split in two at high altitude’
    THE Air France jet that crashed into the Atlantic with 228 people on board broke apart before it hit the water . . . based on the discovery of two trails of bodies more than 50 miles apart, suggesting that the Airbus split in two after going out of control in bad weather and turbulence during its flight from Rio de Janeiro to Paris on June 1. . . . The absence of any traces of an explosion, such as burn marks or inhaled smoke, supports the view of investigators that the disaster was caused by a combination of factors, possibly beginning with the blockage of speed sensors. . . .
    One theory is that the “inconsistent” speed readings caused the automatic pilot to disengage, leaving the crew trying to fly manually – a difficult task at high altitude without knowing the plane’s speed.

    It has emerged that the same sequence of events occurred in six cockpit emergencies reported by Airbus pilots over a year beginning in February 2008. . . .

  159. David L. Hagen says:

    A few more clues/corrections:
    Inquiry Finds French Flight Struck Ocean Intact
    By NICOLA CLARK and MATTHEW L. WALD
    Published: July 2, 2009

    PARIS — The Air France Airbus 330 that crashed into the Atlantic on June 1, killing all 228 people aboard, did not break up in the air but rather hit the water intact, French investigators said on Thursday.
    . . .
    One of the maintenance messages indicated a rapid change in cabin pressure, which might have meant depressurization. But depressurization could occur without breakup, experts said.

    Alain Bouillard, who is leading the French investigation, said that “visual examination of the debris shows that the plane hit with the bottom of its fuselage with very strong vertical acceleration.” Shelves in the galley had compressed to the bottom, he said, among other evidence. . . .

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