Sound Attenuation of Rotary-Wing Aviation Helmets with Oregon Aero(Trademark) Earcup Replacement Products

摘要

The sound attenuation of the HGU-56/P Aircrew Integrated Helmet System (AIHS) and the HGU-84/P Rotary-Wing Helmet System (RWHS) configured with Oregon Aero(Trademark) replacement earcup products was evaluated in accordance with the American National Standard Methods for Measuring the Real-Ear Attenuation of Hearing Protectors ANSI S12.6-1997 (R2002), Method A: Experimenter-supervised fit. Sound attenuation of both the HGU-56/P AIHS and HGU-84/P RWHS configured with the Oregon Aero HushKit(Trademark) replacement earcup foam or SoftSeal(Trademark) replacement earcup seal was essentially equivalent to the helmet's standard configurations. However, the Oregon Aero(Trademark) SoftSeal/HushKit Combo(Trademark), soft replacement earcups provided significantly poorer sound attenuation than the standard configuration. As with the Army's current flight helmet/earcup combination, double protection (i.e., earplugs in addition to the sound-protective flight helmet) is required in certain high noise environments.