Evaluation of V-22 Tiltrotor Handling Qualities in the Instrument Meteorological Environment

Author

Scott Bennett Trail, University of Tennessee - Knoxville

Date of Award

5-2006

Degree Type

Thesis

Degree Name

Master of Science

Major

Aviation Systems

Major Professor

Robert B. Richards

Committee Members

Rodney Allison, Frank Collins

Abstract

The purpose of this thesis is to document the handling qualities of the V-22 tiltrotor aircraft in instrument metrological conditions (IMC) and recommend procedures for V-22 operations in IMC. This evaluation was conducted in the Patuxent River Naval Air Station, Maryland local flying area in accordance with Naval Aviation Systems Command test plan V22-TP-012/02. Test flights consisted of basic instrument maneuvers, en route instrument navigation, instrument approaches, and simulated single engine missed approaches. All maneuvers were conducted under day visual meteorological conditions. En route navigation and instrument approaches were also conducted under simulated IMC using a helmet-mounted hood, and actual IMC. Handling qualities were evaluated for nacelle angle configurations of airplane mode at 0^o nacelle, conversion mode nacelle angles of 30^o, 45^o, and 61^o nacelle, and vertical takeoff and land (VTOL) mode at 80^o nacelle. The handling qualities associated with nacelle angle transitions between airplane mode, VTOL mode, and intermediate nacelle angles were also evaluated. The author participated in this test as a test pilot, basic instrument maneuvers, en route instrument navigation, instrument approaches, and simulated single engine missed approaches.

The stability offered by the fly by wire flight control system resulted in favorable stability and handling qualities for constant nacelle configurations in IMC. The capability to change configuration between airplane mode and VTOL mode or an intermediate nacelle configuration greatly increased flexibility to meet the demands of heavy air traffic or adverse weather conditions during IMC operations. Challenges to handling qualities in the IMC environment included altitude deviations during large nacelle angle changes and the requirement of the pilot to change control strategy for different nacelle configurations.

The author concluded that each nacelle configuration had unique characteristics, which could be used to meet the demands of a given operating environment. While one nacelle configuration exhibited better handling qualities for instrument approaches, other nacelle settings were preferable to meet the demands of heavy air traffic, low ceilings, degraded visibility, and single engine emergencies. It was concluded the pilot should be given the flexibility to choose the best nacelle configuration to meet the demands of the prevailing flight conditions.

Recommended Citation

Trail, Scott Bennett, "Evaluation of V-22 Tiltrotor Handling Qualities in the Instrument Meteorological Environment. " Master's Thesis, University of Tennessee, 2006.
https://trace.tennessee.edu/utk_gradthes/1816