J58/YF-12 Ejector Nozzle Performance

The Lockheed YF-12 aircraft uses a blow-in door ejector nozzle, which consists of a variable area, primary nozzle mounted on the afterburner of a Pratt & Whitney Aircraft J58 engine and blow-in doors, a convergent-divergent spool piece, and variable exit area free-floating flaps integrated into a Lockheed YF-12 airframe. Performance data from cold-flow, wind tunnel models and hot-flow, static stand models were correlated and compared with actual flight test data. It was found that these data showed agreement when both internal thermodynamic and external aerodynamic effects were considered.