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[NEW2elec]

I know this isn't a motorcycle but it just shows what electric can (and will) do in the future with better batteries because the sky is the limit.

http://nextbigfuture.com/2016/07/vtol-electric-two-seater-could-be.html

[Doug S]

Honestly, it escapes me what advantage(s) an electric drivetrain would have in an aircraft. As I see it, the main advantage electric cars and motorcycles have is excellent efficiency over a wide range of conditions, which is great for a car or a motorcycle that has to perform well at speeds from a dead stop to high-speed cruising. But an aircraft just doesn't have to do that. An aircraft is at full power to launch, cruising speed for the great majority of the time, and low speed to land. They don't have to deal with low speed limits or traffic around town.

The EV's biggest disadvantage now and for a while to come is its weight. Batteries don't have anywhere near the energy density of gasoline, so for similar range, I'd think an electric airplane would be at a big disadvantage in terms of weight -- and weight is a HUGE concern in aircraft. Weight requires lift, which the wings are obligated to provide, which causes a dramatic increase in "induced drag"...in other words, a heavier aircraft will always pay a penalty in speed, unlike cars and motorcycles, whose top speed isn't very strongly unaffected by weight. Granted, an electric motor is probably considerably lighter than an ICE, but to provide good range, you'd probably have to have a massive battery in an electric aircraft.

[MrDude_1]

Honestly, it escapes me what advantage(s) an electric drivetrain would have in an aircraft. As I see it, the main advantage electric cars and motorcycles have is excellent efficiency over a wide range of conditions, which is great for a car or a motorcycle that has to perform well at speeds from a dead stop to high-speed cruising. But an aircraft just doesn't have to do that. An aircraft is at full power to launch, cruising speed for the great majority of the time, and low speed to land. They don't have to deal with low speed limits or traffic around town.

The EV's biggest disadvantage now and for a while to come is its weight. Batteries don't have anywhere near the energy density of gasoline, so for similar range, I'd think an electric airplane would be at a big disadvantage in terms of weight -- and weight is a HUGE concern in aircraft. Weight requires lift, which the wings are obligated to provide, which causes a dramatic increase in "induced drag"...in other words, a heavier aircraft will always pay a penalty in speed, unlike cars and motorcycles, whose top speed isn't very strongly unaffected by weight. Granted, an electric motor is probably considerably lighter than an ICE, but to provide good range, you'd probably have to have a massive battery in an electric aircraft.

for large planes.. yes. you are correct.
for smaller planes, the largest expense by far is gasoline. If you build a small plane that carries two people with minimal luggage a short distance without fuel, it will help alot of people with their transportation issues. You wont be going across the country with it, but if you lived on an island or a remote area, it would allow you to easily hop into and out of civilization.

[kingcharles]

You're assuming that the plane needs batteries for range but I think there are other ways of using electric drive in planes.

- Less air pollution and waste of fuel: switch to electric for all taxi manoeuvres. A hub motor in the nose wheel might be enough to make that possible.
- Less restrictions around airports: take off and landing in electric mode reduces sound pollution.
Cruise speed: fossil fuels.
A hybrid system is needed to make this a reality but I think that it's possible!

[MrDude_1]

You're assuming that the plane needs batteries for range but I think there are other ways of using electric drive in planes.

- Less air pollution and waste of fuel: switch to electric for all taxi manoeuvres. A hub motor in the nose wheel might be enough to make that possible.
- Less restrictions around airports: take off and landing in electric mode reduces sound pollution.
Cruise speed: fossil fuels.
A hybrid system is needed to make this a reality but I think that it's possible!

they're already starting to use the wheel motor taxi system... I like the idea, but I do wonder about if the jets need some idle time to warm up before takeoff.

[MostlyBonkers]

You should find this interesting.  Not long range at all, but for its purpose it has many advantage over an ICE plane.

[MrDude_1]

You should find this interesting.  Not long range at all, but for its purpose it has many advantage over an ICE plane.

cool and all, and I admit I skipped around it a bit, but basiclly theres a mockup model airplane, they make some parts from wood... they show how RC parts make good examples... but there isnt anything really THERE... just hopes and dreams.

[NEW2elec]

Dude I watched the whole video and its much past hopes and dreams its closer to builds and test runs. 
As to the advantages of electric its some of the same ones as our bikes.  Instant power and ease of use.  But what puts the for sale signs on planes is the maintenance costs.  Fuel can be high but you can live with it.  Having a certified mechanic tear down that engine after so many hours and go over all the systems fuel, hydraulic, electrical.  That kills the small pilot.

[NEW2elec]

And here it is in action.

! No longer available

[Richard230]

What will they think of next?   

[ctrlburn]

Dude I watched the whole video and its much past hopes and dreams its closer to builds and test runs. 
As to the advantages of electric its some of the same ones as our bikes.  Instant power and ease of use.  But what puts the for sale signs on planes is the maintenance costs.  Fuel can be high but you can live with it.  Having a certified mechanic tear down that engine after so many hours and go over all the systems fuel, hydraulic, electrical.  That kills the small pilot.

A possible solution to that is a "Wing in Ground Effect" vehicle. "WIG" which is the more efficient way to fly... and is not subject to all the maintenance requirements of an airplane (it is actually a boat). BIG drawback is the noise... and along come electric.

In the ongoing saga of electric replacing diesel for me... I have a business plan "Low Flights" for using a diesel "DeltaHawk" airplane engine - brewing biodiesel from coconut oil (coconut oil was the original diesel) and doing and island hopping ferry in the Pacific.  Which now has to be reworked for electric.