Stage III Still Working on STCs for Hush Kit

LaJolla, Calif.-based Stage III Technologies, which in December received an STC for its Stage 3 hush kit for the Gulfstream IISP, expects to receive by the end of summer certification for installation of its kit on the GIII, GIIB and GII, including Stage 1 GIIs. Unlike the already certified systems offered by Really Quiet and Quiet Technology Aerospace, the Stage III system has no moving parts. It adds no more than 40 pounds to the aircraft empty weight, compared with more than 200 pounds for competing kits. Stage III claims a cruise-range penalty of less than 5 percent accounts for the only performance loss. The $2 million (installed) price for the hush kit also includes cascade-type thrust reversers, development of which has contributed to program delays.