STAGE III Technologies is completing a redesign of its planned hushkit for the Gulfstream II and III business jets, and hopes to begin flight tests in October-November. Design refinements resulted from proof-of-concept ground tests completed earlier this year at Dallas Airmotive and Rohr.

Dallas Airmotive has agreed to market the hushkits to satisfy Stage 3 noise limits, and perform installation at six sites around the world. The Dallas, Texas-based company expects to begin installation of flight-test hushkits on a customer's GIII in September. The first production kits are scheduled to be available early in 1998.

Stage III Technologies, based in Coral Gables, Florida, says that its hushkit will allow Rolls-Royce Spey Mk511-8-powered GII/IIIs to meet the Stage 3 noise limits with no degradation in take-off performance, "minimal change" in cruise performance and a 3% increase in static thrust.

The hushkit includes an external mixer-nozzle and fixed-position ejector. Operators of Stage 2 GII/ IIIs will be able to retain the existing thrust-reversers if desired, but hushkitting of older Stage 1 aircraft requires elimination of the thrust reversers, the company says. Stage III and Dallas Airmotive are considering developing a version of the hushkit for the Fokker F28.

Source: Flight International