Flight-path and airspeed control during landing approach for powered-lift aircraft

TLDR

The study analyzes aircraft behavior relevant to pilots controlling flight path and airspeed during the landing approach. The authors evaluated the identified response characteristics using a large‑motion ground‑based simulator at Ames Research Center and compared the results with flight‑test data from three powered‑lift V/STOL aircraft. Manual control of flight path and airspeed during landing approach was investigated, revealing that coupling between flight path and airspeed dominates handling qualities, with key response characteristics including initial flight‑path response, steady‑state coupling, and airspeed sensitivity to pitch changes.

Abstract

Manual control of flight path and airspeed during landing approach has been investigated for powered-lift transport aircraft. An analysis was conducted to identify the behavior of the aircraft which would be potentially significant to the pilot controlling flight path and airspeed during the approach. The response characteristics found to describe the aircraft behavior were (1) the initial flight-path response and flight-path overshoot for a step change in thrust, (2) the steady-state coupling of flight path and airspeed for a step change in thrust, and (3) the sensitivity of airspeed to changes in pitch attitude. The significance of these response characteristics was evaluated by pilots on a large-motion, ground-based simulator at Ames Research Center. Coupling between flight path and airspeed was considered by the pilot to be the dominant influence on handling qualities for the approach task. Results are compared with data obtained from flight tests of three existing powered-lift V/STOL aircraft.