Noise Attenuation Performance of the Joint Service Aircrew Mask (JSAM) Fixed Wing (FW) Variant with Flight Helmets.

摘要

Noise attenuation performance was measured on the Joint Service Aircrew Mask (JSAM) Fixed Wing (FW) variant with the HGU-55/P, HGU-68/P, and HGU-84/P helmets at the Air Force Research Laboratory's (AFRL) Acoustics facilities at Wright-Patterson Air Force Base in March 2011. American National Standards Institute (ANSI) S12.6 and S12.42 methods were used to measure the passive attenuation of the systems. The objective of this study was to identify the noise attenuation performance and determine if the performance requirements were met as defined in the JSAM-FW Performance Specification. The addition of the JSAM-FW degraded the noise attenuation performance when compared to all the helmets alone: the objective (ANSI S12.42) passive insertion loss (across most frequencies) and the subjective noise attenuation (ANSI S12.6) performance (only low frequencies).