Tiltrotor Control Law Development for Handling Qualities Enhancement In the Shipboard Operational Environment

This paper discusses the development and simulation of control law features that enhance handling qualities in shipboard environments and in degraded visual conditions. The control law technologies developed in this paper are intended to improve mission effectiveness and safety while expanding the maritime operational envelope of tiltrotor aircraft. The major control law features discussed in this paper are (1) improved hover, speed, and altitude capture and hold junctions, (2) a Vortex Ring State (VRS) tactile cueing system, (3) automated flight path control during terminal area operations in degraded visual conditions, and (4) phase compensating rate limiter architectures that minimize input-to-output phase loss while limiting the rate of control inputs to allowable levels. The philosophy of the control laws discussed in this paper is to offer seamlessly integrated and failure benign augmented flight control modes using regime recognition. Velocity stabilization functions are automatically engaged or disengaged without button pushes. Piloted simulation of these control law features in the high fidelity Boeing V-22 simulation facility is discussed in this paper.