The use of in-flight manikin recordings for evaluating the communication effectiveness of flight helmets

An exploratory study has been conducted to determine the feasibility of obtaining and using in-flight manikin recordings to evaluate flight helmets with respect to speech intelligibility. Intelligibility test materials were transmitted to six airborne subjects and a manikin as each was fitted with different flight helmets. Similar test materials were presented to the same six subjects in a simulated flight situation. Recordings obtained via the airborne manikin were subsequently played back in the laboratory to the six subjects and two groups of ten listeners each. Comparison of listener scores obtained in the three test situations revealed that scores obtained for the manikin recordings approximated those obtained during the in-flight tests; relative differences among three helmets for the two test situations were very similar. Standard deviations calculated from listener scores obtained for the three test situations revealed less variance for the manikin recordings. The results of the study demonstrate that a manikin head, used in conjunction with a portable tape recorder, can be flown in various types of aircraft to obtain valuable information regarding the communication effectiveness of flight helmets.