Business aircraft cabins are generally not quiet. Not with the turbulent boundary-layer rush of air around the fuselage at Mach 0.85 and the whine of a couple of jet engines no great distance from the comfy chairs. Then there are the pumps, hydraulics, fans, gears, actuators, electric motors, worn bearings and air distribution through the metal ductwork, not to mention the occasional hum of the microwave and induction oven, the rattling of glasses and flatware in the galley and that giant sucking sound coming from the lavatory.
Alto Aviation, a supplier of business jet cabin audio systems, is urging completion and refurbishment centers to rethink speaker grille construction.
“It is one of the most common problems we encounter,” according to the Leominster, Mass.-based company. “Sound waves are made up of the compression and expansion of air [and] if air can’t move through the speaker grille, then the sound can’t get into the cabin.”
Alto recommends speaker coverings that are at least 50-percent open to ensure the best audio performance.
Missouri senator Claire McCaskill (Democrat) hit the nail on the head when she wrote to the FAA about easing rules on the use of portable electronic devices (PEDs) in aircraft. Her letter seeks to have the FAA reconsider restrictions on PEDs, citing as one example the fact that many airline pilots are now using switched-on iPads during taxi, takeoff and landing without any problems.
The supersonic business jet development program continues at Gulfstream Aerospace, but until the FAA decides to define “quiet” as it relates to the so-called sonic boom, “We just don’t see a business case,” said a spokesman.
In a series of patent filings last summer, Gulfstream emphasized mitigating the noise produced by the sonic boom, pointing out that regulations currently prohibit supersonic flight over populated areas.
With the clock ticking toward the start of next year’s World Cup soccer tournament in Brazil, construction is set to begin on São Paulo’s first business airport, which is expected to help handle the influx of private aircraft for the event. Approximately 40 miles from the city, vegetation has been cleared from the future site of the Catarina Aeroporto Executivo’s 8,100-foot main runway and a shorter companion, and bulldozers are scheduled to arrive mid-month when earthmoving permits are issued.
The FAA issued a proposed rule on Tuesday that is aimed at reducing noise generated by new helicopters certified under Part 36 (noise standards) of the FARs. If adopted, the rule would impose standards already adopted by ICAO.
A Gulfstream Aerospace spokesman categorically denied a report published by British tabloid Daily Mail saying that the company, along with NASA, Boeing and Lockheed Martin, would “sketch out” details of a supersonic business jet at the Farnborough Airshow, which starts July 9. Further, Lockheed Martin does not have any civil aircraft announcements planned at the UK airshow.
A new noise-cancelling headset introduced in April at the Aircraft Interiors Expo in Hamburg, Germany, is set to find a market in business and private aviation.
Middletown, R.I.-based Avid claims the headset “effectively reduces environmental external noise by 85 percent with a 20-decibel maximum noise attenuation.” Forty-millimeter speakers, said an Avid spokeswoman, “ensure crisp, clear sound and well defined bass.”
E-A-R Thermal Acoustics Systems (Stand 2145) is improving acoustic insulation aboard business jets as it endeavors to cut the most annoying cabin noises on a case-by-case basis.
Aerion Corp. is preparing to start another round of test flights in the development of what would be the world’s first supersonic business jet (SBJ). A new test article is set to fly in the centerline position beneath one of NASA’s F-15B aircraft in either June or July.
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