Passive Noise Reduction Technology to Improve Speech Intelligibility and Reduce Noise for Pilot and Deck Crew Helmet Mounted Systems

"This SBIR Phase I research will examine methods to provide the Navy aviator with a device that will enhance communications and hearing protection performance that can be used in conjunction with the Navy helmet system. The U.S. Army currently uses aninsert device that significantly improves the sound attenuation and voice communications of their helmet system. There was an attempt with a small sample of Navy aviators to use this technology in the Navy HGU-68 helmet. The attempt was classified asunsuccessful because of discomfort and poor user acceptance. The problems are suspected to be caused by inadequate space within the helmet/earcup and external ear. We will examine the geometry of the external ear and ear canal for a better understanding ofthe space that is available for adequate location of an earphone transducer in the external ear. The geometry assessment will lead directly to improved designs of the housing that contains the earphone transducer. The second goal of the research is todevelop improved foam compositions and configurations that will increase sound attenuation for the user while maximizing comfort. Performance of the device will meet the sound attenuation requirements per DODI 6055.12 for all Navy aircraft and flightconditions. Reduce hearing loss and increase communications performance of aviators."