As pathetic as the March Popular Mechanics article was as a balanced picture of AWE R&D, it did contain hints to the problems the "leaders" are having. 

 

When Joby Energy first announced its intention to develop a jumbo-scale electric autonomous high-duty aircraft capable of VTOL & aerobatic operation, the no-brainer KiteLab prediction was that they could not possibly succeed, given severe scaling penalties, inadequate capitalization, & limited aerospace culture. So its no surprise that Joby has downscaled its target design from a 240ft WS to a 200ft WS, for a nearly 50% reduction in scaling penalty. We previously saw Makani Power's kitesurfer management go through the same process of quietly backing off of 10,000m altitude targets for their flygen kiteplanes, only to end up well under 1000m, for multiple critical reasons. Makanis current scale is around 90ft WS. Somewhere along the line they learned that flying wings are not yaw-stable enough & now they have likely overreacted by adding three tail-booms to the M-1 concept. Three more motor/generators have also been added, for six total, but its still unlikely to perform robust VTOL.

 

The revised KiteLab prediction is that Joby will be forced to continue to downsize drastically & even a "retooled" Makani must continue to reduce its ambitions. Its also probable that given continued poor performance of overrated flygens, the groundgen companies will finally begin to attract major quality investment & take-off spectacularly, while the once hot flygen comapanies languish in the famous VC "valley-of-death", bleakly awaiting maturation of premature dreams.