Thanks, that's very helpful. Looking at Wikipedia's entry https://en.wikipedia.org/wiki/Powered_lift https://en.wikipedia.org/wiki/Powered_lift I don't see any

Thanks, that's very helpful. Looking at Wikipedia's entry https://en.wikipedia.org/wiki/Powered_lift https://en.wikipedia.org/wiki/Powered_lift I don't see any commercially successful aircraft. There are some military aircraft[1], experimental aircraft, and a some unsuccessful commercial aircraft. None is "drone style" yet. Being the first to type certify a new style of aircraft is very difficult and expensive, which was my point with the list of composite aircraft. Composite aircraft (in my mind) seems much less of a change than powered lift. Maybe ballistic recovery systems[2] will make powered lift certifiable with a reasonable level of effort. The nice thing about BRS is that it is already flight proven and accepted as an emergency recovery system. [1] The military is willing to take more risks - helps that the jets have ejection seats. The Osprey had 12 hull-loss accidents with a total of 42 fatalities (no ejection seats and it cannot autorotate). Ref: https://en.wikipedia.org/wiki/Bell_Boeing_V-22_Osprey#Accidents https://en.wikipedia.org/wiki/Bell_Boeing_V-22_Osprey#Accide... [2] https://en.wikipedia.org/wiki/Ballistic_Recovery_Systems https://en.wikipedia.org/wiki/Ballistic_Recovery_Systems