Would imagine these are significantly more useful on heavier and faster aircraft - surely the weight and whatnot to retract move them is less worth it for smaller planes ?
They are commonly used on small single-engine fighter jets as well. They typically cannot be retracted once deployed, and free-fall using their own mass, so there is no actuation system weight to account for.
https://en.wikipedia.org/wiki/Ram_air_turbine
And besides that, there is the looping parachute APU.
https://patents.google.com/patent/US9452721B2/en
Would imagine these are significantly more useful on heavier and faster aircraft - surely the weight and whatnot to retract move them is less worth it for smaller planes ?
They are commonly used on small single-engine fighter jets as well. They typically cannot be retracted once deployed, and free-fall using their own mass, so there is no actuation system weight to account for.