Pipe dream: Norway wants electric airplanes to provide passenger service

WUWT reader “Non Nomen” writes:

Norway now wants to electrify domestic air traffic by 2040.

Will they be able to recharge at every overhead power line?

If they are on medication, they’d better stop that.
If not, they’d better take their pills.


Medication aside, I don’t think these people understand the concept and difficulty of scaling up such technology.

Here is another video worth watching:

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June 22, 2018 12:36 pm

Anthony Watts wrote, “Medication aside, I don’t think these people understand the concept and difficulty of scaling up such technology.”

I think they do.

Boeing Co.-backed startup Zunum Aero plans to deliver its first hybrid-electric plane in 2022 to JetSuite Inc., setting the stage for a new era in regional flying.

JetSuite, a small charter airline with plans to expand a commercial operation nationally, eventually will receive as many as 100 aircraft that seat up to 12 passengers each, Zunum co-founder Matt Knapp said in a statement Monday. JetBlue Airways Corp. has invested in Zunum and JetSuite. The charter operator is also backed by Qatar Airways.

https://www.bloomberg.com/news/articles/2018-05-21/boeing-backed-startup-targets-2022-debut-for-electric-plane

Zunum is designing the propulsion architecture so that higher-performing batteries, electronics and motors can be plugged in over time. This way, the company intends to expand range from 700 nm in the early 2020s to 1,000 nm by 2030.

http://aviationweek.com/aircraft-design/zunum-s-software-style-approach-developing-electric-propulsion

We’ll see.

Non Nomen
Reply to  rovingbroker
June 22, 2018 12:58 pm

We’ll see.

Exactly. When they do as Tesla, another startup with considerable teething problems, did and still does, they are going south.

Walter Sobchak
Reply to  rovingbroker
June 22, 2018 1:21 pm

No we won’t.

Felix
Reply to  rovingbroker
June 22, 2018 1:30 pm

Hybrid prop engine tech has already been demonstrated:

https://www.flyingmag.com/hybrid-electric-aircraft-motor-powers-up

This option is probably the only way that the Green Norwegians can make their deadline.

MarkW
Reply to  Felix
June 22, 2018 1:54 pm

The advantage of hybrid electric is matching engine speed and torque to conditions.
Not a big problem with propellers.

Felix
Reply to  MarkW
June 22, 2018 2:08 pm

Yup. Developing hybrid jets is obviously more challenging.

RicDre
Reply to  Felix
June 22, 2018 2:56 pm

A hybrid Turboprop Jet engine might one day be possible or perhaps a hybrid Turbofan Jet engine since the air from the front fan bypasses the jet engine.

Felix
Reply to  RicDre
June 22, 2018 3:03 pm

They are being worked upon as I type.

RicDre
Reply to  Felix
June 22, 2018 4:24 pm

I’d be very interested to see how they are approaching the technology, do you have a link to an article I could look at?

Felix
Reply to  RicDre
June 22, 2018 4:30 pm

One program:

https://www.zdnet.com/article/boeing-jetblue-invest-in-electric-aircraft-maker-zunum-aero/

Copying some of my previous comments:

There are hybrids today with way over 65 or even 150 hp, and pure electric with more than the former. Not sure about attachment to a Cub, however.

This is from three years ago:

https://www.flyingmag.com/aircraft/siemens-unveils-260-kw-electric-aircraft-motor

“Weighing in at a little over 100 pounds, the new motor delivers a continuous output of 260 kilowatts (the gasoline-piston engine equivalent of about 350 hp), compared with just 60 kw (81 hp) for an electric engine tested in flight by Siemens, Airbus and Diamond Aircraft last year.”

Another:

After setting an electric aircraft record last year, the Siemens electric plane became the first electric glider tug:

https://www.siemens.com/press/en/feature/2015/corporate/2015-03-electromotor.php

This year it suffered a crash.

Siemens’ serial hybrid flew this year in Hungary.

Since 2013, Chip Yates’ electric Rutan Long-EZ has set records and outperformed, at less cost, gas-powered light planes such as Cessnas under FAI supervision.

This technology is more mature than might be imagined, but not ready for multiple passengers yet.

The Norwegians are far from alone:

https://en.wikipedia.org/wiki/Electric_aircraft#Developments

Among the projects listed in that link is this:

http://atwonline.com/airframes/easyjet-joins-electric-aircraft-project

UK (budget carrier) LCC easyJet has formed a partnership with US-based Wright Electric, which aims to develop an 180-seat electric aircraft for commercial aviation use within 10 years. EasyJet said it has been working with Wright Electric “over the course of 2017,” providing “an airline operator’s perspective” on the project in areas ranging from maintenance to revenue management.”

https://www.theguardian.com/business/2017/sep/27/easyjet-electric-planes-wright-electric-flights

Please overlook the source. It’s just quoting the companies.

Who knows whether such an ambitious time table can be met.

A pure electric plane from three years ago in Slovenia, relying heavily on Siemens technology:

https://www.youtube.com/watch?v=WiADDbeFanU

And one in Oz, from five months ago:

RicDre
Reply to  Felix
June 22, 2018 4:39 pm

Thank you for providing the links.

Felix
Reply to  RicDre
June 22, 2018 4:46 pm

You’re welcome. You can find others in this long comments section.

Reply to  RicDre
June 23, 2018 11:02 pm

Electric ducted fans are already a reality in model aircraft. Unfortunately at model speeds they are woefully inefficient and so flight times are short.

MarkW
Reply to  Felix
June 22, 2018 4:46 pm

It’s not just challenging, it’s a waste of effort.

Felix
Reply to  MarkW
June 23, 2018 12:59 pm

Boeing, Siemens and a number of other companies beg to differ.

HAS
Reply to  rovingbroker
June 22, 2018 1:36 pm

Hybrids have a lot going for them. Allows the turbine to run at a constant optimised speed, distributed motors, superconducting motor/generators to compensate for weight.

Current target has them entering service for regional aircraft in early 2030s. Both Airbus and Boeing are developing.

And then of course there are drones.

Felix
Reply to  HAS
June 22, 2018 1:44 pm

Drones would be OK for cargo. Pilotless passenger planes might be a hard sell, even if the aircrew were only along for the ride.

I’d be willing to risk a ride in a drone, however, for short hops, if it had a good glide capability and backup manual controls for emergency landings.

MarkW
Reply to  Felix
June 22, 2018 4:47 pm

In modern jets, the crew is pretty much along for the ride. From takeoff to landing, the crew just monitors.

simple-touriste
Reply to  MarkW
June 23, 2018 11:42 am

And sometimes, the crew is there just to pull the stick in a situation with a high AoA (*): high attitude, negative climb rate and crashes the plane.

(*) yes there is no AoA indicator in either Airbus or Boeing cockpits, I knew there is some debate about whether it would be useful

MarkW
Reply to  HAS
June 22, 2018 1:55 pm

Super conducting motor/generators??????????

Have you factored in the weight of a tank of liquid helium?

HAS
Reply to  MarkW
June 22, 2018 2:22 pm

high temperature superconductors use mechanical cryocoolers with very low power requirements. Also we are just cooling a very small volume, unlike MRIs where the magnets need to be big enough to wrap around a body. All quite doable.

MarkW
Reply to  HAS
June 22, 2018 2:56 pm

Low power is relative. Most of the ones I’m familiar with draw more power than this airplane motor does. Then theirs still the extra weight to deal with.

HAS
Reply to  MarkW
June 22, 2018 4:24 pm

Try “High power density superconducting rotating machines—development status and technology roadmap” Haran et al 2017 iopscience.iop.org/article/10.1088/1361-6668/aa833e/pdf to get you started. Add to that completely sealed cryostats with coils that are excited inductively to reduce load. Remember power is required at ~50K not 4K.

MarkW
Reply to  HAS
June 22, 2018 4:48 pm

I didn’t say they weren’t possible, just not practical for this application.

HAS
Reply to  MarkW
June 22, 2018 7:54 pm

Yes you did, but that view was based on your knowledge of low temperature superconductor technology. When it was pointed out that you had the technology wrong you just refer back to your original mistake. Can’t help you anymore, sorry.

MarkW
Reply to  HAS
June 23, 2018 12:38 pm

You haven’t provided anything beyond vague assertions.
Pretty typical.

RicDre
Reply to  MarkW
June 22, 2018 2:33 pm

“Super conducting motor/generators??????????”

I was wondering about the same thing. I thought maybe someone had invented room-temperature super-conductors and I missed the announcement.

David Hoopman
June 22, 2018 12:45 pm

Decades ago I concluded that the stupidest thing you could possibly do is jump into your car and drive it until you run out of gas. Now I can move something even more stupid to the top of my list.

John Harmsworth
June 22, 2018 12:58 pm

Why settle for electric? Catapult launched gliders or ballistic passenger capsules wouldn’t require any carried energy at all!
Or just catapult people directly.

Non Nomen
Reply to  John Harmsworth
June 22, 2018 1:44 pm

Oars and rows and paddles for the passengers and a competent drummer, and off they go.

MarkW
Reply to  John Harmsworth
June 22, 2018 1:56 pm

They tried that to get free range immigrants over the border.
They are still working on mastering the landing.

Reply to  MarkW
June 22, 2018 2:57 pm

The landing is easy. The hard part is walking away from the landing.

Jim

jorgekafkazar
Reply to  John Harmsworth
June 22, 2018 4:14 pm

Catapults are noisy:

John Harmsworth
June 22, 2018 1:03 pm

I know we’re supposed to be polite but do we have to be patient and tolerant much longer with these Green idiots? I’m going to explode pretty soon!

Bruce Cobb
Reply to  John Harmsworth
June 22, 2018 1:14 pm

Laughing at them works wonders – very therapeutic, and they hate it. Win-win!

drednicolson
June 22, 2018 1:18 pm

Snoopy’s doghouse looks like a safer plane ride than that.

Toto
June 22, 2018 1:19 pm

ATTN: Elon Musk. The Norwegians are really good at drilling tunnels.

dmacleo
Reply to  Toto
June 22, 2018 1:36 pm

bet an aircraft like this can drill one faster…..

MarkW
Reply to  dmacleo
June 22, 2018 1:57 pm

At 300kg, it wouldn’t dig a very deep tunnel.

June 22, 2018 1:43 pm

Lets not forget that this kind of dismissal followed the Wright brothers’ <100m flight. The small plane depicted is a fair start. Who knows,maybe they can be recharged continously in flight, microwaves? Maybe they could refuel passively using powerlines' magnetic fields… My point is you should write your article to define the limitations and what possible technologies might be tried. At some point we will have to fly someway without petroleum fuels. Hopefully we dont consider converting half of American agriculture to corn fuel to make things worse.

Non Nomen
Reply to  Gary Pearse
June 22, 2018 1:47 pm

Power lines brought more a/c down than recharged them. Microwaves are a safe method to heat up the passengers until they explode.

Reply to  Non Nomen
June 22, 2018 2:02 pm

Its hard to make a difficult point

Clyde Spencer
Reply to  Gary Pearse
June 22, 2018 3:42 pm

“At some point we will have to fly someway without petroleum fuels.”
Why? As someone pointed out above, av’ gas can be made from things other than crude oil.

M___ S___
June 22, 2018 1:46 pm

People seem not to be able to do the barest research—to check on energy density. The only way we’ll see electric aircraft is if they are using fuel cells that convert fossil fuels to electricity first, and then they use the electricity to drive electric motors—propellers only.

Keep in mind that these politicians are no better than 99% of our own politicians—incompetent people making decisions and creating edits for all of us.

John Mason
June 22, 2018 1:48 pm

Looking at the Wikipedia article on Energy Density it’s about a 40 to 1 ish advantage in power per weight of current aircraft to an electric one.

Perhaps by 2040 there will be some break thru, but without that, electric aviation is just not going to feasible or competitive.

In a ground vehicle the weight of the batteries can be handled to a certain degree that we have some vehicle applications that work (light duty commuting or long distance if the vehicle can switch to gas like the Chevy volt or Honda clarity).

For me, when I’m on a long road trip looking for 900 miles in a day even the long distance electric car solutions aren’t tenable. Quick replaceable battery packs like people exchange propane tanks was one approach, but the car makers have nothing remotely standardized with their batteries. So we are left with the charging stations.

In that state, electric cars are still not competitive and when the whole life cycle of the electric vehicle including the fossil energy require to mine and make and later dispose of the battery, I doubt there is any CO2 savings at all. It’s all virtue signalling.

Order of magnitude * 4 for aviation.

John Hardy
Reply to  John Mason
June 23, 2018 9:23 am

John Mason: 900 miles a day is an edge case, but if you insist: https://www.theverge.com/2018/1/2/16842816/tesla-model-3-la-new-york-record-cannonball-run. Tesla Mosel 3 2800 miles LA to NYC in 50 hours

Auto
Reply to  John Hardy
June 23, 2018 11:17 am

Ah. The Mosel 3.
Run entirely on German white wine.

Bit of a waste, in my opinion.

Auto

Sheri
June 22, 2018 1:50 pm

There is a complete lack of reality in these people’s lives. They live in a dreamworld and for some reason, rational people keep electing them. Or we live in the dreamworld and the people who elect them are rational……

Marcus
Reply to  Sheri
June 22, 2018 2:14 pm

An electrical battery fire at 10,000 ft would really light up their “dreamworld” !!

drednicolson
Reply to  Marcus
June 22, 2018 9:42 pm

For maximum poetic impact, the plane ought to be named Icarus.

richard verney
June 22, 2018 1:53 pm

It’s a toy. An expensive plaything for the wealthy.

When I lived in Norway, there were lots of small sea planes at the bottom of people’s garden who lived on the islands in the Fjord. Great for hopping to see the neighbours for a BBQ, but presently nothing more serious than that.

June 22, 2018 2:06 pm

The film reminds me of this old clip of demonstrated steam powered aircraft shortly before they became commercially viable: https://www.youtube.com/watch?v=_yowX1_1sEg (sarc)

dodgy geezer
June 22, 2018 2:08 pm

It’s a big model aircraft….

shrnfr
June 22, 2018 2:36 pm

Of course, thorium reactors were being developed to do exactly this. Perhaps it is time to go back and dust off the blueprints. We do not need so much plutonium these days. We have enough bombs. http://www.businessinsider.com/aircraft-nuclear-propulsion-molten-salt-reactor-2016-12

Gamecock
June 22, 2018 2:45 pm

As often happens with these theatrical technology presentations, the actual achievement is NOT in what is promoted.

The great achievement here is the plane itself, not the electric drive train. That thing might fly with a 5hp Briggs & Stratton.

Felix
Reply to  Gamecock
June 22, 2018 2:53 pm

Not that different from a light sport aircraft.

Three types of Light Sport Aircraft. In the foreground, an E-LSA Antares USA Ranger weight-shift control trike. In the background, an S-LSA Evektor SportStar and an L-LSA Zlin Aviation Savage Cub:

comment image?download

Their owners hate it when you call them “ultralights”.

MarkW
Reply to  Felix
June 22, 2018 2:59 pm

With the exception of the kite in the foreground, everyone of those air craft carry way more in passengers and cargo and can all fly a lot longer than 1 hour at a time.

For that matter, the kite in the foreground has the same passenger and cargo passenger capacity as the plane in the video. It probably has a similar speed and range as well.

Felix
Reply to  MarkW
June 22, 2018 3:37 pm

Yup on the kite.

MarkW
Reply to  Felix
June 22, 2018 4:49 pm

I’m guessing it costs around an order of magnitude less as well.

Felix
Reply to  MarkW
June 22, 2018 9:50 pm

Yes, but without much promise of future development.

Ve2
Reply to  Felix
June 23, 2018 9:56 pm

They hate it more when you call them a crumpled heap of duralium.

Mike M.
June 22, 2018 2:51 pm

A solar powered horse could pull back a giant rubber band to launch a sling shot airplane. With a good sized draft horse ( 5 ton pull) you could probably go a couple miles on a nice day if the wings don’t fall off. (Maybe even up there long enough to wake up after the initial G’s?)

Pierre
June 22, 2018 3:15 pm

Now let me get this straight. We are going to carry big high density high amperage batteries on a passenger plane! I won’t fly on one.

GoatGuy
June 22, 2018 3:15 pm

So…

Its like there is an alternate reality universe in which the Green Goblins live, and refuse to acknowledge physics, whether packaged as aerodynamics, payload fraction or energy intensity.

So…

The problem of batteries is as a technology for powering aircraft all comes down to kWh/kg. Not volume (they’re not fluffy down pillows, nor anchors of pig iron), not output power (completely sufficient when scaled with kWh). The very, very best battery options availabe today, and even tnose envisioned for the next 10 years (being the time-to-market for today’s various announcements and hints-for-future-tech), just don’t exceed 0.5 kWh/kg.

FUEL CELLS — where the “battery guts” is separated from the ion-generating “fuels” which are stored in some variation of tanks, are the eletric equivalent of internal combustion engines. Fuel + oxygen (ICE) → engine → heat + mechanical power → transmissions to convert torques. For the fuel-cell it is something like electronegative ion A + electropositive B → fuel cell → heat + electrical power → motors … giving mechanical power.

Thing is, CONVENTIONAL BATTERIES have “fuel” (A+B) contained in usally-but-not-always smallish cells, hooked massively in parallel into banks, those in series into large batteries. And they weigh a LOT. The remarkably well-and-thoughtfully engineered-for-safety-and-heaps-of-power-production TESLA Model S (85) battery weighs in at 1,200+ lbs (550 kg), stores 85 kWh of useful power, and has all interlocks, per-cell fusing, anti-flammability and other protections built in. OUT THE DOOR spec is 85 kWh ÷ 550 kg → 0.156 kWh/kg.

So…

As I said above, the most aggressive claims for near-future all-in, all-packaged tech for any weight sensitive use is something like 0.50 kWh/kg, or about 3.2× better performance than a Tesla energy anchor. At the very least, when working with airframes and aloft-mass-budgets, you can substitute stainless steel frames, cells, banks, hardware with titanium. No problem. Well, except for catching fire. You could even lighten it further with carbon-fiber composite materials, where utile.

But that’s about it.
_______

Looking at the flight profile though of just about any commercial aircraft, what becomes immediately obvious is that if “100% power” is needed for some part(s) of the flight, it is clear that 35% to 50% is needed during most of the rest of the flight. The CRUISE portion.

This — at least to anyone who was born after 1950 — immediately suggests the optimizing crux solution. HYBRID architecture. Storing hugely mass-efficient liquid fuel aboard at just under 4 kWh/kg (without needing to also store the oxygen!) is quite a win for providing most of the energy required for the nominal flight. A much smaller and lighter weight set of batteries could then be required JUST to service that “100% parts” of the flight. Hybrid. Battery storing a bunch of extra power for a bunch of extra thrust (becoming extra lift) to climb to altitude. To get to full cruise speed.
But then the “next part of the sanity-check” comes into play.

Because you see, there are these pernickety beings called PASSENGERS that don’t want to use air travel that goes at the Speed of Smell™. They are accustomed to air travel times from under an hour to well under ⅓ of a day … for most points of domestic travel. And — not for Norway, tho’ perhaps — but the United States, ⅓ of a day, 8 hours at 450 knots nominal speed is a whole lot of miles. Seattle to Tampa. San Diego to Boston. Honolulu to San Francisco. New York to Milan. London to Chicago. Reykjavik to Los Angeles “over the pole”‘.

And those require 400 to 500 knot, 10,000 meter (35,000 ft) flight.

Even the shortest hops that we regularly use as domestic travelers — within nominally commercial air traffic corridors — by propeller planes are still “turbofan” designs, with 250–300 knot airspeed expectations. Can’t tell you the number of last-minute el-cheapo LAX → SFO flights I took on mid-sized Saab prop planes over the years. Seating for 25 to 85, LAX → SFO in under 2 hours (regular jets do it in about 60 minutes), but nowhere near a taxing trip. Noisy and comfy. As the booby prize, the single attendant just handed out free everything. Beer, wine, nuts, crackers. Consolation for being late-out-the-gate (always!!!), slow and noisy, and much easier than making dumb penny-change for the fliers.
Still… it was fine.

I think I and the other 25 to 85 passengers (these flights were ALWAYS totally full) were satisfied with “the deal”. Fast enough, endurable enough.

Question is, what was the power required to accomplish this? The Saab 340 weighed about 12,000 kg at takeoff, powered by a pair of GE 1,300 kW (1,750 HP) turbofans; Cruise 250 knots, ceiling 25,000 ft, range 900+ nautical miles, 34 passengers, 2 pilots, 1 attendant. 3,220 liters of JP–1 jet fuel at takeoff. 3,000 kg worth. Cruise at 40% full power at 25,000 ft, at 250 knots. You do the math.

40% of (2 × 1,300 kW) → 1,000 kW nominal during cruise.
80% of (900 knot ÷ 250 kt/h) = 2.9 to 3.0 hr aloft
3.0 h × 1,000 kW = 3,000 kWh.

IF that were battery, even at 0.5 kWh/kg, that’d be 6,000 kg of battery. At something closer to 0.30 kWh/kg (figuring Tesla tech, in light-weight packaging and only modestly improved internal cell chemistry), you’re talking 10,000 kg. In battery. For JUST the cruise part.

Compare that back to the 3,000 kg of jet fuel. Jet fuel kind of wins. Because the mass of a jet engine to convert it from liquid fuel to rotary power is absolutely no more than the same power permanent super-magnet type 500 kW (ea) output motors and electronics. Not with FAA tolerances, safety and overkill.

_______

This is why I think its generically “nuts” to consider all-electric domestic flight. Either its going to have to be slower (with the public upsold as to why), or its going to have to be hybrid. There’s no alternative.

UNLESS we get awfully lucky and serendipitously discover some unimagined-so-far battery chemistry which takes us cleanl over 1.5 kWh/kg. 40% of jet fuel. At that point, it’d work.

Just saying…
GoatGuy

GoatGuy
Reply to  GoatGuy
June 23, 2018 7:40 am

Also: that 3,000 kg of jet fuel, converted to kWh of motive power directly is about 3.5 kWh/kg so that is roughly 10,000 kWh of jet-engine produced energy. For the WHOLE trip at longest range … 900 nautical miles.

Even if “400 nautical miles” is chosen as the acceptable puddle-hopper range, you’re still looking at over 5,000 kWh of motive power required for the plane. Maybe more. At 0.35 kWh/kg, 5,000 kWh becomes 14,500 kg. Clearly this weighs MORE than the entire fueled-up and ready-to-take-off Saab 340 with 30 passengers (12,000 kg at TKO of which 3,000 kg is fuel).

Building a plane around a 15,000 kg battery is going to take another 10,000 kg of airframe, motors, seats, electronics, cubby space, and so forth. With a takeoff weight of close to 30,000 kg, and a complete inability to shed ‘fuel mass’ during flight(!!), I doubt very much that a 5,000 kWh plane is going to do better than 150 knots, and give only 200 nautical miles of range.

All that for all-electric flight?
Need WAY better batteries.

GoatGuy

drednicolson
Reply to  GoatGuy
June 23, 2018 9:26 pm

Apparently, with aluminum-air and lithium-air batts, you would gain mass during flight, as the metals oxidize during discharge.

Felix
Reply to  drednicolson
June 23, 2018 9:33 pm

Yes. Slightly.

GoatGuy
Reply to  Felix
June 24, 2018 10:09 am

4 Al + 3 O₂ → 2 Al₂O₃
4 × 27 + 3 × 2 × 16 = 204 whereas (4 × 27 aluminum = 108).

The take-up doubles the mass of the original reacting aluminum. Not “slightly”.

And the rather dissapointingly practical problem is that aluminum hydroxide naturally bonds with H₂O to for gelatinous alumina “hydrated hydroxides”. Which take up much higher volume than either the aluminum or the anhydrous oxide.

Since H₂O is also bound with the (Al₂O₃) production takes mass … it is consumed by the electrochemical cell and must be resupplied externally. But for aircraft, this is yet another dead weight burden. That and either making enough room in each cell to take the overburden of hydrous aluminum oxide volume-wise, or coming up with an active electrolyte-and-plate scrubbing technology that elutes the sloughed off gel, captures it, and one presumes… that without too much weight penalty or reliability-and-cost add-on, recovers the alumunium oxide and separates the bound water, again for use back in the cells.

Just saying, tho’ really attractive, the aluminum-metal + air battery is very likely not to suddenly become the predominant tech, cheap and also light-weight.

GoatGuy

Reply to  GoatGuy
June 23, 2018 11:41 pm

GoatGuy: First of all a rousing cheer from me for making the real points so clearly BUT with one exception.

I doubt very much that a 5,000 kWh plane is going to do better than 150 knots, and give only 200 nautical miles of range.

I suspect this is where your understanding of aerodynamics falls short. So did mine until I started thinking about it during my electric model plane heyday 15 years ago…

The power to sustain (cruise) flight is a function of the planes weight and lift to drag ratios ONLY.

If you want a faster plane, chop off its wings. You will reduce drag, and lift in pretty much equal proportions.

A light plane can take off at 50mph and maybe have a top speed of 150mph. A jet airliner takes off at 180mph and has a top speed of 550 mph.

In all cases for efficient use of fuel there is about a 3:1 ratio between stalling speed and top speed. Jet liner are designed to fly at high altitude where they can – due to less atmosphere being there – fly faster for the same drag. However it takes a long time and a lot of energy to get there, so thats only viable for long haul.

What a given amount of energy storage gets you is either maximum altitude or maximum DURATION.

SPEED is not actually in the equation except insofar as if you try and break the sound barrier, your lift to drag ratios become appalling, and energy use climbs dramatically.

Thats is why commercial planes fly a little under the speed of sound. They actually consume fuel at similar rates per lb of aircraft as a light plane doing 100mph, but speed means more passengers per year. And thats means more profit out of the airframe. Whose costs of capital is in terms of percent interest per year. (In fact that, and the reduced downtime for engine maintenance is what drove the almost overnight switch to jet passenger planes in the 1960s. It is also the reason that jet engines are in pods under the wings. Easier to service/swap out = less downtime)

So at subsonic flight speeds, what a given amount of fuel buys you is altitude and duration, or both. Speed can be anything you want, and as range is a function of speed, so too can be the range. Up to a practical limit of say 500mph.

Currently I’d say a BEA (battery electric aircraft, not British European Airways) could do an hour in the air. Giving it a practical range of say 400 miles at a top speed of around 400mph.

Beats a WWII Spitfire anyway 🙂

The trade off for high flight speed is of course a high take off and landing speed. Even with massive increase in wing area and huge flaps a modern airliner can’t really fly at less than 130mph. Hence 4 mile runways instead of a cricket pitch to fly from…

(You wont see a better example of a dead stick landing on a sixpence than this: Ernst Udet in the 1930s – https://www.youtube.com/watch?v=1VdXVowLKQ0 – a large wing area biplane using massive sidslip to act as airbrakes . kills the planes speed and dumps it for a 50 meter rollout – if that. If he had had wheel brakes… )

(Actually I forgot the adapted STOL cCubs that delight in this sort of thing https://www.youtube.com/watch?v=bPSElw8qEsI )

Anyway my point is that you wont ever see that kind of landing from a jet airliner,. although you might from a Hawker Harrier..

So thats my lengthy objection to one phrase. Electric model planes already do way better than 150 knots.

And I would guess personally that 400 miles range is on. Otherwise I agree with you totally.

How much payload? Not a lot.

Big Bubba
June 22, 2018 3:20 pm

There is possibly one application for electric that no-one has mentioned: assisted take off for gliders.
The norm is a tow plane for getting in the air, and if you don’t fancy a tow there are gliders with pop up (and retractable once airborne) petrol motors. Electric might be a good exchange for them?

Felix
Reply to  Big Bubba
June 22, 2018 4:01 pm

After setting an electric aircraft record last year, the Siemens electric plane became the first electric glider tug:

https://www.siemens.com/press/en/feature/2015/corporate/2015-03-electromotor.php

This year it suffered a crash.

Siemens’ serial hybrid flew this year in Hungary.

Since 2013, Chip Yates’ electric Rutan Long-EZ has set records and outperformed, at less cost, gas-powered light planes such as Cessnas under FAI supervision.

This technology is more mature than might be imagined, but not ready for multiple passengers yet.

The Norwegians are far from alone:

https://en.wikipedia.org/wiki/Electric_aircraft#Developments

Among the projects listed in that link is this:

http://atwonline.com/airframes/easyjet-joins-electric-aircraft-project

UK (budget carrier) LCC easyJet has formed a partnership with US-based Wright Electric, which aims to develop an 180-seat electric aircraft for commercial aviation use within 10 years. EasyJet said it has been working with Wright Electric “over the course of 2017,” providing “an airline operator’s perspective” on the project in areas ranging from maintenance to revenue management.”

https://www.theguardian.com/business/2017/sep/27/easyjet-electric-planes-wright-electric-flights

Please overlook the source. It’s just quoting the companies.

Who knows whether such an ambitious time table can be met.

Reply to  Big Bubba
June 23, 2018 11:42 pm

Already exist.

June 22, 2018 3:35 pm

Don’t know what all the fuss is about, an electric aeroplane can fly quite well using electricity. All that is needed is some technology that will allow efficient handling of the extension cords between the airports. 🙂

Cheers

Roger
🙂

Non Nomen
Reply to  Roger
June 22, 2018 10:53 pm

The a/c are hooking on the overhead power lines. Norway has many of them. Some are really, really dangerous. They catch a/c in flight and bring them down.

drednicolson
Reply to  Non Nomen
June 23, 2018 9:29 pm

And the lower the craft’s flight ceiling, the more likely it is to take a high-voltage clothesline.

John the Econ
June 22, 2018 4:24 pm

Actually, I’m excited about this technology. If the cost of an hour of general aviation flight could get down below $20/hr from the >$100 it largely is today, I’d jump back in. Mind you, with the current state of this technology, I wouldn’t consider cross-country flights, or even venturing far past the landing pattern. After all, I can’t remember how many times have I picked up a supposedly intelligent battery powered device that proclaimed that it was ready to go with a multi-hour charge only to have it die on me less than 30 minutes later. But just to be able to bounce around a traffic pattern and practice touch & go’s inexpensively at my local airport would be great.

As for scaling this up to anything that would be commercially viable to replace contemporary airliners, it won’t happen, at least for a very long time and until some other radical breakthroughs are achieved on many levels. For one thing, these hyper efficient and lightweight planes are barely capable of 100 mph, versus 250 to 350 for turbo-prop commuters and over 500 for jets. In other words, considering the slow speed and frequent stops for recharging required for a cross country trip of any significant distance and the associated costs of keeping passengers for long periods of time, you’d get there faster and cheaper by just driving.

Yirgach
Reply to  John the Econ
June 23, 2018 6:45 am

The second video from the top indicates a low cost per hour because they assumed the cost of the electricity was 0.
Anyway, that’s the way I read it.

John the Econ
Reply to  Yirgach
June 23, 2018 6:59 am

The cost of electricity is a fraction of the equivalent amount of energy in gasoline. Also consider that the aviation gasoline that most general aviation aircraft use costs much more than the automotive variety, usually $5 to $7 dollars per gallon in the US at the moment. But that is not the only advantage. What an electric plane does is turn the economics of general aviation on its head. Not only is the “fuel” much cheaper, but so is the maintenance. Most general aviation engines only have a 2000 to 3000 hour life before they must be overhauled or replaced. Those overhauls and replacements typically cost $20,000 and up. Of course, the anticipated cost of that, along with required maintenance is factored into the hourly cost of operating one of these planes. Electric motors with few moving parts should theoretically last indefinitely.

Yirgach
Reply to  John the Econ
June 23, 2018 11:39 am

Thanks for the reply. Besides the costs of fuel and maintenance the other greater cost, which is the elephant lurking in the room, is safety. Until there multiple miracles in battery design – storage, density, safety yet alone overall systems integration and performance, there will be no safe advantage. I’ve flown enough to know what can happen during a flight and also at the most dangerous times, which is landing and takeoff (I’m not a pilot, just a thankfully alive passenger).
Experienced an aborted landing at OHare where we were 100 ft off the ground, a real roller coaster ride. Then multiple lightening strikes over the years, not to mention windshear and altitude drops similar to the Vomit Comet. Protection against these “speed bumps” requires a lot more energy, frame strength and resiliency than is currently available for this technology.

I will concede that in 50-100 years that MAY be over come, I just do NOT want to be an early pioneer.
Note to self – steer clear of air taxis in Norway.

Felix
Reply to  Yirgach
June 23, 2018 11:51 am

Surely safety design concerns and challenges exist, but being surrounded by up to 50,000 gallons of kerosene is also a hazard in case of a crash.

drednicolson
Reply to  Felix
June 23, 2018 9:50 pm

Fuel can be jettisoned in an emergency to reduce weight and fire risk, while retaining enough to keep control of the plane.

5000 kg batteries aren’t so easy to dump. And just imagine one of those impacting in somebody’s backyard.

Gamecock
Reply to  John the Econ
June 23, 2018 11:51 am

Turn around time another killer. Commuter jets can be refueled in minutes.

I remember when a Hawaiian Airlines 737 lost its roof. They said it had made 90,000 flights (!).

Felix
Reply to  Gamecock
June 23, 2018 11:52 am

PV cell-coated aircraft refuel themselves in flight. With IR spectrum cells, they can even do so at night.

And advances in battery technology will grant electric a/c longer range.

Reply to  Felix
June 23, 2018 11:53 pm

O purlease!

The A380 is the world’s largest airliner. … Wing Area, 845,0 m²…typical full sunshine insolation at midday at the equator 1kw/sq m

So 845kw. times 20% solar panel/drive train efficiency

It takes around 4 watts per pound to keep an airbus in cruise, or roughly 10 watts per kg, so at best we can fly an airbus weighing 845000 x 0.2 x 0. 1 kg …= 16.9 metric tonnes off a solar panel at midday on the equator.

An Airbus a 380 is 360 metric tonnes empty.. take off weight is around 560 tonnes.

PLEASE go away Felix and learn to Do Basic Sums as well as how to roll a spliff.

Felix
Reply to  Leo Smith
June 24, 2018 12:19 am

As I keep repeating, no one is talking about jumbo jets.

Flight Level
June 22, 2018 5:13 pm

Some facts. Solar impulse, wing load 15kg/m2. Airbuses and other fifi’s fly in the realm of 150kg/m2 of wing load. Anyone with appropriate education realizes at this point that the flight envelope of Solar Impulse is very similar to a kite. That’s why it lands after sundown to avoid even the slightest thermal.

To this day some V’s have been kept top secret for that contraption. An educated guess places Vne in the 2 digit numbers. An otherwise common gust can disassemble Solar Impulse, reason it has never been flown in any but uber-friendly weather.

As the chart’s room saying goes, climate does not kill. weather does.

Salon aviation for armchair green would be pilots. Fueled by ignorance optimism turns generally ugly and Solar Impulse was excellent at demonstrating it without casualties. Game over.

A go-round in a battery operated A/C can become harrowing, even more so since take off and landing weights are identical unless depleted batteries are jettisoned in mid-air.

One amongst the (too) many reasons why no self-respecting PIC should accept to expose pax to green fantasies.

How many times do we have to scream it out ? Planes are not fork-lifts ! They don’t need batteries as stabilizing ballast deadweight to prevent capsizing while carrying loads.

Felix
Reply to  Flight Level
June 22, 2018 6:03 pm

Solar Impulse repeatedly flew at night, albeit slowly. It took days of continuous flight to cross from Japan to Hawaii.

But for the distances traveled by regional airlines, it could reach higher speeds during the day. Its cruise speed under photon capture was 56 statute mph, but was capable of higher velocity. It needed the heavy batteries to fly at night.

A daytime only, all-electric plane would actually make sense even with today’s tech.

Flight Level
Reply to  Felix
June 23, 2018 9:55 am

Oh my my… Felix, your intervention is a brilliant example of why aviation requires that much training of which you exhibit evidence of none.

Reality is that airmanship and airworthiness are very closely related to maths. Let’s give it a go in a rather simplified way, would we ?

So if you equate the power required for a fixed wings level flight at constant airspeed to the power you could gather from the available surface considered as covered with photovoltaic cells, you’ll discover that, funny enough, the surface cancels out on both sides of the equation.

Leaving you with a cruise speed depending solely on the A/C aerodynamic and weight characteristics.

That’s in a bright light with that much of total energy falling per unit of surface.

Scaling up becomes nonsenical. Size simply cancels out on both sides of the equation.

Harrowing shear terror for someone who knows that airspeed and altitude are the most precious commodities for safe flying.

A solar powered aircraft has an absolute upper cruise speed llimit, educated guess, in the lower 3 figures for the most optimal airframes.

Things get ugly at altitude where winds of 250 knots are not that uncommon. Rendering boundary transitions a delicate exercice even for airframes whose Vne is in the upper realm of 4 figure numbers.

Turbulences, airholes and other things nice do exist, trust me on that. How bad can they be ? Figure the cabin crew service cart leaving a serious imprint of it’s shape on the upper cabin lining.

That’s why requlations require at least one pilot to be permanently buckled at all times. And much more.

The good thing with tolar A/C is that they cancel the paper trail a PIC is supposed to endure after a close encounter with a weather system on steroids, hail and presumably lighting strike.

Yep lightening. One of the best way to ruin your concentration on that crosswords while en-route. That’s quite a sound and light-show, paperwork and probably a dime of chipped paint for a liner. A no-event.

However your milleage might seriously vary on a fully composite electrically powered airframe covered by interconnected PV cells.

We take icing very seriously. A totally no-jokes topic. Jets are blessed as they have more than enough power to spare for heating their critical and control surfaces while turboprops carry anti-ice boots and a serious payload of optimism.

Anti-icing is a costly commodity since most of time it’s just a deadweight with stringent maintenance schedules. Until the moment when the “shields up” call becomes a life saving necessity. Happens also in summer BTW 😉

Airframe icing is a cummulative hazard. It depends on where you’ve been, what’s the weather sandwich you’re in and the noise-abatment craziness du jour, just to quote a few.

Not all landings are finalized. Some have to be aborted for various reasons, weather inclusive. Just another day at the office unless engine power becomes scarce. Then it quickly becomes the last day at the office. Inclusive for the souls who paid for their supposedly safe trip.

In other words a very ugly situation for a solar powered aircraft without significant reliable power reserve and flight characteristics a kite could be proud of. Tilt, game over, crosswinds win.

Well Felix, I could spend my evening writing down reasons why, despite the quest for profits, solar A/C are not a suitable transportation means.

Educating you is out of my roster.

Now it’s your turn to document yourself on the topic. And let those who pride themselves in the safety of their PAX and the souls under do what they’re supposed to do.

I’ll call it quits, it’s been a bumpy day despite the seemingly perfect sun-tan and barbecue inciting weather all over a few clouds down…..

Felix
Reply to  Flight Level
June 23, 2018 12:10 pm

You’re missing the point that SI 2 is only a concept demonstrator. It should be obvious that a commercial aircraft would be more substantial.

The issue is power, and advancing battery and PV tech promise to provide it. With more power, airframes can be sturdier (also thanks to materials science) and an excess of reserve power can be made available.

Reply to  Felix
June 23, 2018 11:56 pm

No Felix, the issue is that you cant do maths, dont understand physics and have about as much engineering comprehension as the average amoeba.

June 22, 2018 5:14 pm

Simple question of energy density.

jmorpuss
June 22, 2018 5:50 pm

“Wireless high power transmission using microwaves is well proven. Experiments in the tens of kilowatts have been performed at Goldstone in California in 1975[73][74][75] and more recently (1997) at Grand Bassin on Reunion Island.[76] These methods achieve distances on the order of a kilometer.”
https://en.wikipedia.org/wiki/Wireless_power_transfer

tty
Reply to  jmorpuss
June 24, 2018 2:37 am

Most aircraft tend to operate over distances larger than one kilometer. And wireless power transmission, while possible, is insanely wasteful, and highly dangerous for any living thing caught by the beam.

Hivemind
June 22, 2018 7:33 pm

This is actually a very practical proposal for Norway. Their people can drive half an hour North, South, East or West and be out of the country, where they can catch a normal aircraft to get to where they want to go.

The idea is really nothing but virtue signalling.

Felix
Reply to  Hivemind
June 22, 2018 7:48 pm

The fact that other airlines are aiming to get electric and hybrid short haul aircraft in service even sooner doesn’t mean that it’s not virtue signalling. But it could also be driven by fuel cost savings, low noise levels, maintenance or other operational considerations.

https://www.wired.com/2017/04/hybrid-jet-finally-make-electric-flight-reality/

It’s possible that Safran S.A., Boeing, Airbus, Raytheon, etc are virtue signalling or subsidy farming, but I don’t think so. Could be that they’re anticipating technilogical advances.

The next generation of batteries Obviously will need to deliver a lots of power at the same time as being smaller, safer and lighter than lithium-ion ones.

Scientists have made progress. For instance, MIT’s Dr. Qichao Hu has invented a polymer ionic liquid that allows batteries to hold double the energy of current lithium-ion models. Making batteries lighter will increase the energy savings and flying range of airplanes. Who can say what advances will occur in the next ten to 20 years?

http://www.solidenergysystems.com/

In the meantime, hybrid aero engines hold promise of savings.

Reply to  Hivemind
June 24, 2018 12:02 am

Have you ever looked at a map of Norway in your life? From Oslo to Tromsö is over 700 miles as the plane flies, or over 1000 miles of road.

And that’s not even the greatest distance in Norway.

The country is over 1000 miles long!

Felix
Reply to  Leo Smith
June 24, 2018 12:44 am

As I said, there is no commercial air route in Norway of 870 statute miles. Alta is 770 miles by air from Oslo (twice a day, WX permitting) and Tromso 713.

Don’t have to look at a map. I’ve been there.

tty
Reply to  Felix
June 24, 2018 2:43 am

Oslo-Longyearbyen is about 1250 miles. Been there too.

Felix
Reply to  tty
June 26, 2018 1:37 pm

IMO the electric commercial service probably wouldn’t go to Svalbard.

You’ve been in some cold places.