FlyMachine79

The forefather of the Dune 'Thopters'... from way back in the late '30s! Unfortunately, it did not proceed beyond the testing phase but showed promise especially had the second prototype been completed which was to feature a much-improved wing design.

https://oldmachinepress.com/2017/11/20/riout-102t-alerion-ornithopter/

https://preview.redd.it/ypjax3166tx81.jpg?width=1200&format=pjpg&auto=webp&s=4eafd4e1fca99436ab959030ee01497c6818f676

The Wren STOL Skylane was and still is the ultimate STOL Skylane.  Developed in the 1960s by Robertson,  the Wren STOL conversion is an extremely labor-intensive conversion that gives the Skylane a full span Fowler flap, using "Wren's Teeth" on top of the wing to add roll control. These "Wren's teeth" look like giant moving VG's and rotate with the ailerons.  The Wren also features a canard with elevators coupled to the original elevator controls, allowing the Wren to climb with remarkably flat pitch compared to the standard Skylane.  The Wren was heavily used in Southeast Asia in the Air America efforts and spawned a range of enhanced Skyalnes called 'Katmai Kings' with Tundra gear, canards

On January 11 1978 the first 'American Jet' (later Gulfstream) Hustler prototype flew its maiden flights as a single-engine aircraft on the P&W PT6-41Turboprop, certification flights were flown in 1979 on both engines (P&W JT15D-1 in the tail). The published performance specs were as follows: Maximum cruise speed 400kts with climb rates up to 4950ftpm, economy cruise range 2000nm on both engines stretched to 2550nm just on TP power at 30 000ft, respectable for its class and its time. The idea was to offer the duel economy option of flying on either jet or turboprop power. Later development saw a Garret powerplant in the nose. The project was ultimately suspended due to the recession