Communication earplug offers aircrews hearing protection

  • Published
  • By Maria Callier
  • Air Force Office of Scientific Research
ARLINGTON, Va. --  AFOSR-sponsored research has led to a communication earplug that revolutionizes hearing protection for Air Force pilots and flight crews and could substantially reduce hearing loss and improve radio communication.

The breakthrough research, led by Dr. Laura Ray of Dartmouth College, enabled the researchers, engineers and product developers at a technological company called, Sound Innovations, Inc. to develop a new active noise reduction system, at the heart of the new earplug design. The new device is expected to impact the work of active-duty soldiers by protecting and enhancing their hearing, allowing clear, two-way communication in noisy environments and enabling them to effectively listen to sounds from a distance.

"Dr. Ray worked out the mathematics to successfully conjoin noise control algorithms for the first time in a highly stable, hybrid system. This scientific breakthrough enables a much more robust approach to noise cancellation for the acoustically dynamic conditions encountered around aircraft engines," said Dr. Willard Larkin, AFOSR program manager for the project.

"One of the primary challenges was to develop an electronic module for the earplug that could operate for 15 to 20 hours on AA batteries. We were able to use cutting-edge processor technology for developing a lower power electronics module," said Professor Ray.

The earplug has high fidelity audio for clear speech, wide frequency range, light head-borne weight and replaceable ear-tips. It is stored in a small pouch that is attached to an airman's flight vest and delivers communication signals through the earplugs, which are worn under the helmet.

The product was tested for design verification, evaluated for operational use and then the first generation of earplugs was flight tested at over a half dozen Air Force bases. The second generation is expected to have reduced power consumption, size and weight and will be used with a new aircrew helmet.

In the meantime, Dr. Ray is continuing to explore ways to improve the earplug's ability to enhance communication and noise reduction.

"The main challenges that I plan to address are delivering communication through headsets in such a way that the listener can perceive the environment as if using 'natural' hearing. The listener will focus on sounds that he wants to hear, while helping to 'tune out' ones that are distracting," she said.