Steady deep stall landings using lifting surfaces in propeller flow and wing articulation

Deep stall landings can allow fixed-wing aircraft to operate from highly constrained spaces. A deep stall landing maneuver is characterized by operation in a narrow, high-α regime from which recovery is difficult, if not outright impossible, and control authority along all three rotational axes is limited. The problems of maintaining a low flight speed as well as adequate control authority are addressed in this paper. We consider an aircraft where the wing as well as the horizontal tail lie in the propeller flow stream, which allows these surfaces to generate enough lift and pitching moment to trim at low speeds. Using force and moment balance, we derive a set of design pointers for aircraft which seek to operate in the deep stall regime. Finally, we investigate the use of wing articulation for lateral-directional control at high alpha.