Pilot Performance, Strategy, and Workload While Executing Approaches at Steep Angles and With Lower Landing Minima

Abstract

Objective: We examined the willingness and ability of general aviation pilots to execute steep approaches in low-visibility conditions into nontowered airports. Background: Executing steep approaches in poor weather is required for a proposed Small Aircraft Transportation System (SATS) that consists of small aircraft flying direct routes to a network of regional airports. Method: Across two experiments, 17 pilots rated for Instrument Flight Rules at George Mason University or Virginia Tech flew a Cessna 172R simulator into Blacksburg, Virginia. Pilots were familiarized with the simulator and asked to fly approaches with either a 200- or 400-foot ceiling (at approach angles of 3°, 5°, and 7° in the first experiment, 3° and 6° in the second). Pilots rated subjective workload and the simulator recorded flight parameters for each set of approaches. Results: Approaches with a 5° approach angle produced safe landings with minimal deviations from normal descent control configurations and were rated as having a moderate level of workload. Approaches with 6° and 7° approach angles produced safe landings but high workload ratings. Pilots reduced power to control the speed of descent and flew the aircraft slightly above the glide path to gain time to control the landing. Conclusion: Although the 6° and 7° approaches may not be practical for routine approaches, they may be achievable in the event of an emergency. Application: Further work using other aircraft flying under a wider variety of conditions is needed before implementing SATS-type flights into airports intended to supplant or complement commercial operations in larger airports.