Electric planes could revolutionize flight, from commuting in air taxis to making regional flights more affordable and long-haul flights more environmentally friendly. So in the era of electric cars, why are planes so far behind? » Subscribe to CNBC: cnb.cx/SubscribeCNBC » Subscribe to CNBC TV: cnb.cx/SubscribeCNBCtelevision » Subscribe to CNBC Classic: cnb.cx/SubscribeCNBCclassic About CNBC: From 'Wall Street' to 'Main Street' to award winning original documentaries and Reality TV series, CNBC has you covered. Experience special sneak peeks of your favorite shows, exclusive video and more. Connect with CNBC News Online Get the latest news: www.cnbc.com/ Follow CNBC on LinkedIn: cnb.cx/LinkedInCNBC Follow CNBC News on Facebook: cnb.cx/LikeCNBC Follow CNBC News on Twitter: cnb.cx/FollowCNBC Follow CNBC News on Instagram: cnb.cx/InstagramCNBC #CNBC Why Don't We Have Electric Planes Yet?