Heating measurements on Space Shuttle Orbiter models with differentially deflected elevons

The phase-change paint technique was used to make heat-transfer measurements on five Space Shuttle Orbiter models with differentially-deflected elevons. The outboard elevons were deflected windward through an angle delta when the inboard elevons were deflected through an angle - 2delta, where delta = 0, 5, 10, 15, and 20 deg. The models were tested in air at Mach 6 and Mach 10 with two different flow conditions at each Mach number. Each test was run at three angles of attack; 20, 28, and 35 deg. This study was restricted to the windward side of the wing/elevons area. Multiple chord-wise streaks of high heating often occurred on the wings and sometimes extended to localized spots of high heating on the windward-deflected elevons. The extent of heating was a function of angle of attack and test conditions, but in general differential deflection of the elevons affected the wing heat-transfer coefficient on the order of 40 percent or less whereas the windward elevon heat-transfer coefficient was a function of the deflection angle and could be many times the value determined for the undeflected elevon.