Agreed. Legally, GA aircraft under visual flight rules must have at least 30 mins reserve so currently this thing wouldn't be allowed to fly!<p>Battery powered aircraft aren't completely impractical though. This Chinese electric 2 seater has a 40KW brushless electric motor, 400lbs of payload and up to 3 hours of endurance:
<a href="http://www.flyingmag.com/pilot-reports/lsa/sport/electrics-emerge" rel="nofollow">http://www.flyingmag.com/pilot-reports/lsa/sport/electrics-e...</a><p>The downside is it's slow (60mph), but if the engineering challenges for lithium-air batteries are ever solved you'd have a serious competitor to piston aircraft. Not to mention that electric engines are far more reliable than piston ICEs and you don't have to worry about fuel fires (just don't use Sony batteries ;-)