This investigation was part of a larger study conducted by Memphis State University. This laboratory's portion of the study focused on administering conventional audiometry (manual and self-recording), high-frequency audiomerry (4–18 kHz), and a speech intelligibility test in noise to 108 Naval Aviation Officer Candidates prior to and following primary flight training in T-34 aircraft. Hearing protection consisted of either the APH-6C or APH-6D flight helmet. Cockpit noise levels in the T-34 range from 96 to 115 dBA; during cruise the noise level is approximately 100 dBA. Results indicate no significant change in hearing sensitivity or speech discrimination that could be attributed to noise exposure during primary flight training. Pre- and post-primary hearing levels obtained for the high frequencies compare favorably with high-frequency hearing levels obtained by Northern et al. (1968) for males in the age range 20–29 years. Questionnaire data indicated that a considerabte number of the subjects had been exposed to potentially hazardous noise before entry into military service.