On Tuesday, April 14, 2020 at 2:14:17 AM UTC-4, Tim Taylor wrote:
The last few comments on this thread are a really not useful. Each aircraft fits a specific mission. There has been mentioned of needing redundant engines, needing hours of engine operation time, etc, etc. We are not flying airplanes, they are gliders first with motors to allow either take-off or the abilty to sustain.

There is no right answer, each fits the needs of the pilot. Some may want a few miles of sustaining (traditional turbo or non-launching FES), some may want just enough to launch, some want both, snd some want redundant systems so they can fly out of reach of safe landing sites.

Each design is a compromise and ultimately has to fit the needs of the owner. There is no right or wrong design. Arguing over which one is better is like arguing over which flavor of ice cream is better.

I'll describe the requirements I am trying to satisfy for me with my project. I suspect this is much like many but obviously not all.
1) The glider needs to be practical for one person to assemble in a reasonable period of time without heavy lifting. This means a ship that is not more than about 100 lb heavier than it's similar non powered counterpart.
2) Self launch capability with acceptable margins. I am using a takeoff distance of 900 feet, off pavement, and climb rate of at least 400 feet per minute. Ability to fly off unpaved surface knowing takeoff distance will increase.
3) Battery capacity for a 2000 foot launch and 2500 feet reserve to save and get home or to a safe airport.
4)System must have sufficient motor cooling to allow high power settings long enough to get to a safe altitude before power reduction.
5) Practical charging. In my project the battery can be removed for charging away from the glider.
6) Existing proven airframe.
This is my "Wednesday afternoon" ship for when I have no tow pilot.
FWIW
UH