Duncan Aviation expects by the first quarter of next year to receive group STC for RVSM in the Gulfstream II. The avionics package will consist of dual IS&S air-data computers, dual IS&S altimeters and interface units. Duncan’s goal is to keep the installed price below $200,000. Installations would be available from Duncan facilities in Battle Creek, Mich.; Lincoln, Neb.; Van Nuys, Calif.; and Teterboro, N.J.