City Hall tests airplane muffler to reduce noise at SMO
SMO — Santa Monica city officials, Justice Aviation and residents are collaborating on a possible solution to one of Santa Monica Airport’s most vexing problems — the constant drone of airplanes over the neighborhoods.
Justice Aviation, the largest flight school at SMO, has agreed to install the airplane equivalent of a muffler on one of its Cessna 172s to see if the device, still uncommon in the United States, will cut down on the noise generated as planes fly in the airspace around the airport.
Members of airport staff, a Justice Aviation pilot and two members of Community Against Santa Monica Airport Traffic, or CASMAT, gathered on Dec. 6 to take initial readings of the noise generated by the small airplane as it traveled roughly 10 times in a box around SMO, often called “the pattern.”
Assuming the weather cooperates, the plane will complete the same maneuvers on Monday, this time with a muffler-like device by the German company Gomolzig, which was installed on the airplane this week.
Officials will then compare the two readings and decide whether or not the system, called QuietFlight, should be recommended to airplane owners that frequent SMO.
The idea of the muffler was first suggested in May on a post to the CASMAT website, said John Fairweather, founder of the organization.
“They’ve been doing this for 20 years or more in Europe,” Fairweather said. “The United States is kind of behind in noise mitigation.”
According to manufacturer Gomolzig’s website, QuietFlight lowers the sound impact caused by airplane exhaust by reflecting the sound waves created by the plane, decreasing their intensity and converting the energy into heat on solid surfaces.
Gomolzig representatives came out to an “Open House” at the airport to give a presentation on the technology. City Hall then purchased a muffler, which was still being installed on Justice’s plane on Thursday.
On Dec. 6, city officials, alongside Fairweather and Lloyd Saunders, also of CASMAT, gathered to take the initial readings. While city officials relied on noise monitors in line with the airport’s runway, Fairweather took other readings to the side of the flight path using decibel monitors.
“I was basically in Sunset Park off to the side taking the noise measurements,” Fairweather said.
The pilot tested various scenarios, including the noise abatement procedure, a route that turns over the Penmar Golf Course, a 270-degree departure and various forms of take offs and landings to get a full range of readings.
The group will replicate the test with the muffler on Monday, assuming the weather conditions are similar enough to the first test almost two weeks before.
Even a change in the humidity can have an impact on the accuracy of the test, Fairweather said, comparing it to the experience of sound in a fog where noises can appear louder.
Joe Justice, owner of Justice Aviation and the test plane, is restrained in his discussion of the muffler.
The cost of the device and installation is somewhere within the $4,000 to $5,000 range, he said, putting it beyond the means of many pilots or plane owners.
“It’ll be interesting data, and maybe a few planes will be able to have it installed,” Justice said.
Fairweather, on the other hand, sees even the willingness of City Hall to participate in the test as movement in a positive direction, particularly since City Hall has expressed a willingness to share the test results.
“This is a new era of openness and trying to work together,” Fairweather said. “This is not a whole solution, but any improvement is better, right?”
The concept of putting mufflers on planes may sound somewhat obvious to almost anyone who’s driven in a car, but it’s hardly the only commonplace technology to have passed the aircraft industry by.
Smaller planes still use leaded fuel, something that was phased out of street vehicles since 1995. Satellite-driven air traffic management has also eluded aircraft, although cars have had global position systems devices (GPS) for years.
The Federal Aviation Administration is working on that with the implementation of NextGen, which will allow for aviation-specific versions of GPS.
