Hearing Thresholds among Pilots and Non-Pilots: Implications for Auditory Warning Design

Observations in simulator studies suggested that the older segments of the General Aviation pilot population were having difficulty hearing specific auditory warnings in the cockpit. These observations, in combination with data from Tobias (1968a; 1968b; 1972), prompted a reexamination of the hearing capabilities of pilots and non-pilots. In Phase 1, threshold data were collected for 150 non-pilots and 150 pilots using stratified age sampling. The usual higher-frequency decrements attributable to aging and general environmental exposure were found in both samples. Significant differences were found between the non-pilot and pilot samples, with greater threshold shifts between 2 and 6 kHz in evidence among the pilots. In Phase 2, individuals were exposed to simulated aircraft engine noise and asked to detect and identify both conventional and novel auditory warning sounds. Results of both phases are discussed in terms of implications for the design of auditory warnings for General Aviation aircraft.