Quiet Technology Aerospace (QTA) has applied for approval of an operating procedure that brings its Gulfstream II/III hushkit in under "marginal Stage 3" limits being introduced by a number of European airports.

"Certain airports in populated areas where noise is a bigger issue can apply for approval of a noise limit 5dB below Stage 3," says Martin Gardner, director of engineering. Citing Amsterdam Schiphol and Stockholm Bromma airports, he says Paris also uses marginal Stage 3 as the noise limit for night flights.

Stage III Technologies says its Gulfstream II/III hushkit reduces cumulative noise to 5.3bB below Stage 3, allowing the Rolls-Royce Spey-powered business jets to meet the marginal Stage 3 limits. Both companies are battling for the 400-aircraft Gulfstream II/III hushkit market.

Gardner says QTA can reduce cumulative noise to 5.1dB below Stage 3 with a reduction in maximum take-off weight of 2,270kg (5,000lb) and in maximum landing weight of 3,630kg. Even with the reduced weight, he says, the GII can still do a full-payload transatlantic trip, but the GIII will need a fuel stop on Europe-US trips.


Source: Flight International