Julie K. Boatman AOPA Pilot June 2002
"After a long flight, it takes awhile before you really stop moving. The hours of absorbing vibration from the engine and propeller leave our bodies tired and our minds in a fog. Though we identify high frequency noise as a fatigue-inducing culprit and use all manner of noise-reducing headsets and insulation to get rid of it, we often fail to recognize the low frequency vibration that also saps us of energy. When a teenager pulls up next to you in his car, radio booming. you feel the bass in your chest. In an airplane, another kind of heavy-metal band is rocking under the cowl, and you're sitting in the front row.
is installing a noise-reduction system in light aircraft that promises to reduce this low-frequency noise."
"Throughout the hour-long flight, we cycled the ANCS on and off, testing various headsets, both passive and ANR, to determine what benefit the system produced, and how it compared to headsets alone. Initially, when the ANCS is turned on, you cannot tell much of a difference. Dean Rushfield, engineer and demo pilot for Quiet Flight compared it to how your eyes adapt to a dark room. All your senses adapt in this way when you cook dinner with a lot of garlic you lose sense of it's strength after a while. When Rushfield flicked the switch off, the change was dramatic the engine and prop thundered again."
"Another cool thing about the ANCS is that it's constantly working to optimize the nullifying waves that it generates. Say you fly through some turbulence. You can hear the wobble in the noise signature as the system adapts. Overall, Quiet Flight estimates an 8 to 12 decibel reduction and keep in mind that equates to a 50-percent reduction in sound pressure or noise."
Dianne White Twin & Turbine September 2001
" ...There's no denying it. Cessna 310's like all twin piston and turboprop aircraft are noisy.
The engines, props and slipstream still create a great deal of racket in the cockpit and cabin
"This inherent noise has created a virtual cottage industry within general aviation: noise-canceling headsets, Q-tip props and improved door seals and noise-absorbing insulation. While all of these have been employed with varying levels of success, a true noise-eliminating solution has either been too expensive or simply not available for most older twin aircraft.
"But that's changing. Based in Dallas, Quiet Flight is a small company with a big idea. Using electronic noise attenuation technology, the company is marketing a system that eliminates the low-frequency noise and vibration generated by the engines and props. The result is a quieter cabin, reduced fatigue and a more comfortable ride for both pilot and passenger. And the price? Less than you'd pay for the latest panel-mounted GPS."
"A few weeks ago, this author took a demonstration flight on board John Bowman's Cessna 310. My five-year-old daughter, already a pilot-in-training, tagged along
"At all RPM settings, there was a noticeable drop in the sound levels when the system was operating. I could easily converse with both John and Abby who sat directly behind me. By adding noise-canceling headsets, the aircraft cabin was especially quiet.
"However, the biggest difference was the decrease in the vibration one feels in the chest and stomach. When John disabled the system, you could immediately feel the "thump" of the props even when they are synched. It was similar to feeling the "whomp" of the bass guitar at a rock concert. A concert is one thing, but it is quite another when your body must undergo that sound vibration for a three-hour trip. After a 30-minute flight, it was obvious that the system makes for a much more comfortable ride.
"Although I could clearly hear and feel the system at work, my daughter Abby gave the best testimony of the system's effectiveness. After we touched down at DuPage, I turned back to check on her. She was sound asleep. Now that's a comfortable ride!"