Identification of aircrew tasks for using direct voice input (DVI) to reduce pilot workload in the AH-64D Apache Longbow

Advances in helicopter design continue to saturate the pilot's visual channel and produce remarkable increases in cognitive workload for the pilot. This study investigates the potential implementation of Direct Voice Input (DVI) as an alternative control for interacting with onboard systems of the AH-64D Apache, in an attempt to reduce pilot workload during a "hands on" the controls and "eyes out" condition. The intent is to identify AH-64D cockpit tasks performed through Multi Purpose Displays (MPDs) that when converted to DVI will provide the greatest reduction in task execution time and workload. A brief description of applicable AH-64D audio and visual displays are provided. A review of current trends in state-of-the-art voice recognition technology is presented, as well as previous and current voice input cockpit identification studies. To identify tasks in the AH-64D, a methodology was developed consisting of a detailed analysis of the aircraft's mission and on-board systems. A pilot questionnaire was developed and administered to operational AH-64D pilots to assess their input on DVI implementation. Findings indicate DVI would be most useful for displaying selected MPD pages and performing tasks pertaining to the Tactical Situation Display (TSD), weapons, and communications. Six of the candidate DVI tasks were performed in the AH-64D simulator using the manual input method and a simulated voice input method. Two different pilots made objective and subjective evaluations. Task execution times and workload rating were lower using a simulated means of voice input. Overall, DVI shows limited potential for workload reduction and warrants further simulator testing before proceeding to the flight environment.