Electric cars- i was just reading about the 08 tesla roadster, very nice, seems efficient... even for a plane?

Question

would electric motors implement well into experimental aircraft? im assuming the biggest challenge is the heavy battery but are they reliable enough? it seems mech. motors for air need to stand very long loads at high rpm since theres no tranny, this i propietary of an electrical motor so why hasnt anyone tried it

Answer 1

electric plane like Sonex and AeroConversions  E-Flight Initiative http://www.batteryvehiclesociety.org.uk/...

? current flight time of 45 minutes per charge

or solar powered round the world Hy-bird due next year?http://www.batteryvehiclesociety.org.uk/...

Answer 2

Battery weight is the killer. Electric motors are more efficient and more reliable than gasoline engines (only one moving part!!).

But weight is key. Gasoline energy density is about 46 MJ per kg. For batteries, the range is 0.13 to 0.46 -- at least a hundred times more weight for a given amount of energy for batteries, compared to gasoline. Electric motors are about 90% efficient compared to about 25% for internal combustion engines, but even allowing for that, the energy weight for batteries is still dozens of times higher.

For cars and boats, weight is no big deal. But for airplanes, it's huge.