HANDLING QUALITIES EVALUATION OF THE ADOCS PRIMARY FLIGHT CONTROL SYSTEM

A handling qualities flight evaluation of advanced flight control law concepts was conducted on a modified UH-60A Black Hawk helicopter as part of the Army's Advanced Digital Optical Control System Program (ADOCS). The ADOCS demonstrator aircraft included an advanced fly-by-light digital control system developed specifically for the scout/attack (SCAT) helicopter mission. The capability to re-configure multi-axis side-stick controller (SSC) configurations was provided to evaluate configuration effects on handling qualities. Catagory B and C tasks were performed with the unaugmented UH-60 to compare a fully integrated four-axis SSC with various separated SSC configurations. Results from piloted flight evaluations were compared to results from previously conducted simulations performed while developing the ADOCS side-stick controllers and control laws for unaugmented flight. Though changes were made to system parameters, no major modifications to the control law structure occurred. Primary Flight Control System (PFCS) feed-forward shaping to provide control quickening for unaugmented flight was evaluated in addition to an automatic trim follow-up algorithm designed to reduce pilot workload. Pilot ratings from flight test evaluations of the unaugmented UH-60, including landings and ground operation, show that Level 2 handling qualities were obtained for all tasks performed with separated side-stick controller configurations. Level 2 handling qualities were not achieved for all tasks performed with the integrated four-axis controller. Results from flight evaluations conducted using the production UH-60 mechanical controls were also presented. Comparison of data show that unaugmented handling qualities of the UH-60 flown with either the production system or with the DOCS (with separated controllers) are Level 2 for all tasks performed.