WIND-TUNNEL TESTS OF A JET-STREAM SPOILER TO IMPROVE THE SEPARATION CHARACTERISTICS OF A STORE CARRIED BENEATH THE WING OF HIGH-SPEED AIRCRAFT

Wind-tunnel tests at Mach numbers of 0.55 to 0.90 were conducted on a jet-stream spoiler in a 0.05-scale aircraft model which carried an underslung store. The jet-steam spoiler was a compressed-air jet directed out into the wind stream from an aerodynamic surface. This jet device was placed with the nozzle directed from the aircraft lower wing surface onto the rear portion of the store. The purpose of the tests was to improve the release characteristics of the store by alleviating the large negative pitching moments which occurred on the carried store. The test results showed that the small jet-stream spoiler reduced the store pitching moment magnitude only slightly. However, some spoiler configurations did reduce the positive store normal force to zero or negative values, and this could improve the store separation characteristics. (Author)