MIT analysis of battery powered aircraft

[GregLocock]

TLDR? Nope

https://www-technologyreview-com.cdn.ampproject.org/c/s/

http://www.technologyreview.com/2022/08/17/1058013/electric-planes-taking-off-challenges/amp/

Cheers

Greg Locock


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[IRstuff]

Doesn't seem like much as changed nor are there any simple solutions in the near future

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

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[rb1957]

no, there are no simple solutions. but if we can find a niche for electric planes then the market will develop, and develop better batteries. I mean, look at the V22 ... with enough money and time we can make almost anything work !?

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

 

[kontiki99]

The current US regulations for VFR fuel reserves require enough fuel to land with 30 min of reserve fuel onboard. IFR operations must be able to land with 45. IFR aircraft may have to fly to an alternate field owing to weather below minimums for a second approach though. So, that means enough fuel to fly to a destination, fly the approach, go missed, climb to cruise get to an alternate destination, fly that approach and land with 45 min reserves.

Given all of that, expecting the same performance from an electric airplane, maybe a regional island hopping operation or route structure with very short flight times would be the only passenger service I'd envision.

As always, the artist renditions look really cool on the cover of Aviation Week though!



My posts reflect my personal views and are not in any way endorsed or approved by any organization I'm professionally affiliated with.

 

[rb1957]

reserves are a reason for an APU driving a generator to recharge, if needed. Of course there are issues with an almost fail-proof starting (of the APU ... ie must start when needed).

And once there you may as well use it as a range extender ... ?

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

 

[dik]

Unless you have a green power source, it's self defeating... You cannot use fossil fuel to make the power that charges them... big problem with Tesla autos...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[rb1957]

ok, how about electric powered airships ?

As I see it there are three options ...

1) find ways to deploy the electrical power systems we have today. This would require govt subsidy, and may involve very limited airplanes, or 1/2 measures (like FF powered APUs), but the point is to push the technology along.

2) bemoan the state to current technology, and do nothing.

3) ground all FF powered planes (and see our civilization implode).

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

 

[Macm_020171]

There are a few new manufacturers developing electric aircraft that are designed for certain type of missions, with ranges around 100 miles for 4 passengers 1 pilot for commuting in big cities. For this kind of operations they are pretty much optimized. It seems there is an important market for this kind of aircraft (EVTOLS) Larger than that, I believe electric has no future, unless a revolutionary battery technology is developed. The future will probably be hydrogen for large aircraft or hybrid electric/hydrogen for medium size aircraft.

 

[MintJulep]

ok, how about electric powered airships ?

Yes, and we could use hydrogen for both lift and power! Doubly green!

Oh, wait......

But seriously, electric lighter-than-air might fill some niche and novelty use cases - the exact same ones that fossil fuel powered lighter-than-air fills today.

Regardless of power source, they are slow, and have a limited operational envelope relative to weather.

 

[kontiki99]

I believe current practices for industrial production of hydrogen involve cooking methane which is not really a green process. Maybe solar farms could do water electrolysis on a large enough scale to be cost effect but, that's not how it's done now. I've read there are some industries that require hydrogen fuels now, I don't recall which ones, methane is the current source.

My posts reflect my personal views and are not in any way endorsed or approved by any organization I'm professionally affiliated with.

 

[SwinnyGG]

Unless you have a green power source, it's self defeating... You cannot use fossil fuel to make the power that charges them... big problem with Tesla autos...

You've expressed this sentiment a lot in various threads.. and it's not correct.

 

[enginesrus]

If planes are electric they would have to be propeller driven again. If so there is a way to do the same right now and massively cut the use of jet fuel to maybe 2/3 rds or less that what is used now.
And dik, the greenest fuel there is comes from the earth, yes good old mineral oil.

 

[btrueblood]

"there is a way to do the same right now and massively cut the use of jet fuel to maybe 2/3 rds or less that what is used now."

No. You've posted that crap before, and been proven wrong. Jets, turboprops, and reciprocating props, form a spectrum, and the most efficient engine depends on distance and payload.

 

[drawoh]

GregLocock,

Is it worthwhile to convert existing aircraft into electric aircraft?

Weight Summary                                          lb     kg
Empty weight with all fixed equipment except weapons  6544   2970
Pilot and parachute                                    200     90
Fuel, 523 litres (115 gallons)                         860    390
Oil, 45 litres (10 gallons)                             96     44
Two MG151/20 20mm cannon                               196     89
Ammunition for above (2 × 200 rounds)                  200     96
Two MGFF 20mm cannon                                   126     57
Ammunition and magazines for above (2 × 55 rounds)      90     45
Two MG17 7.92mm machine gun                             56     25
Ammunition for above (2 × 1000 rounds)                 142     64
Radio equipment                                         70     31
                                                      8580   3890

Here are the weights of a Fw[ ]190A captured by the British. This comes from Arco Aircraft Classic No 2 [—] The Focke Wulf Fw[ ]190, by Gordon Swanborough and William Green. Note the weight of the fuel. Fuel, ammunition and cargo must be placed somewhere near the aircraft's centre of mass. A battery's mass ought to change very little. The battery(s) can go anywhere in the aircraft.

I would expect an aircraft designed from the ground up as electric, to look different from current, conventional aircraft. This does not solve the problem of battery life, but it creates opportunities for better cargo configuration. If the batteries moved from the fuselage to outboard in the wings, could the wings be made a bit lighter?

--
JHG

 

[GregLocock]

Goodness knows, the (first and) last aircraft I designed for real was when I was 14! I imagine it'll be the same as with cars, the requirements are so different that a ground-up redesign pays off, but you can certainly make a flyable/drivable conversion. You didn't break out the engine weight 1250 kg and the oil cooling system. The engine was initially rated for 1147 kW.

Funnily enough despite my first para I am just putting a more robust worksheet together, on the basic parameters for an a/c, I'll use the electric Fw as a test case.

Late edit, my long term collaborator on battleship weirdness wrote one already,

http://rocketpunk-observatory.com/home.htm

. So I'll start there.

Cheers

Greg Locock


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