Modem control laws are developed for the AH-64D Longbow Apache to provide improved handling qualities for hover and low speed flight in a degraded visual environment. The control laws use a model following approach to generate commands for the existing partial authority stability augmentation system (SAS) to provide both attitude command attitude hold and translational rate command response types based on the requirements in ADS-33E. Integrated analysis tools are used to support the design process including system identification of aircraft and actuator dynamics and optimization of design parameters based on military handling qualities and control system specifications. The purpose is to demonstrate the potential for improving the low speed handling qualities of existing Army helicopters with partial authority SAS actuators through flight control law modifications as an alternative to a full authority, fly-by-wire, control system upgrade.

This paper is located in the AHS International 62nd Annual Forum (TL716 .A1 A512 2006 VOL.3).