On Wednesday, April 1, 2015 at 2:33:12 PM UTC-6, son_of_flubber wrote:
This approach is cleaner

http://www.youtube.com/watch?v=zpluCYve9qw&t=5m32s

OK, with full recognition that it's April 1st, an electric ducted fan has some advantages for self-launch in that ~60 knots is right in the middle of the "sweet spot". It could beat any open prop's thrust/Watt ratio at that speed.