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This paper provides an overview of the activities associated with the aerodynamic database which is be-

Computational uid dynamics tools have been used extensively in the analysis and development of the X-43A Hyper-X Research Vehicle. A signi cant element of this analysis is the prediction of integrated vehicle aeropropulsive performance, which includes an integration of aerodynamic and propulsion ow elds. The development of the Mach 7 X-43A required a pre ight assessment of longitudinal and lateral-directional aeropropulsive characteristics near the target ight-test condition. The development of this pre ight database was accomplished through extensive aerodynamic wind-tunnel testing and a combination of three-dimensional inviscid airframe calculations and cowlto-tail scramjet cycle analyses to generate longitudinal performance increments between mission sequences. These increments were measured directly and validated through tests of the Hyper-X ight engine and vehicle owpath simulator in the NASA Langley Research Center 8-Foot High Temperature Tunnel. Predictions were re ned with tip-to-tail Navier-Stokes calculations, which also provided information on scramjet exhaust plume expansion in the aftbody region. A qualitative assessment of lateral-directional stability characteristics was made through a series of tip-to-tail inviscid calculations, including a simulation of the powered scramjet ight-test condition. Additional comparisons with wind-tunnel force and moment data as well as surface pressure measurements from the Hyper-X ight engine and vehicle owpath simulator model and wind-tunnel testing were made to assess solution accuracy. Nomenclature C A = axial force coef cient C l¯= rolling moment derivative, /deg C M = pitching moment coef cient C N = normal force coef cient C n¯= yawing moment derivative, /deg C p = pressure coef cient C y¯= side force derivative, /deg X; Y; Z = spatial coordinates, m ® = angle of attack, deg

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The successful Mach 7 and 10 flights of the first fully integrated scramjet propulsion systems by the Hyper-X (X-43A) program have provided the means with which to verify the original design methodologies and assumptions. As part of Hyper-X's propulsion-airframe integration, the forebody was designed to include a spanwise array of vortex generators to promote boundary layer transition ahead of the engine. Turbulence at the inlet is thought to provide the most reliable engine design and allows direct scaling of flight results to groundbased data. Pre-flight estimations of boundary layer transition, for both Mach 7 and 10 flight conditions, suggested that forebody boundary layer trips were required to ensure fully turbulent conditions upstream of the inlet. This paper presents the results of an analysis of the thermocouple measurements used to infer the dynamics of the transition process during the trajectories for both flights, on both the lower surface (to assess trip performance) and the upper surface (to assess natural transition). The approach used in the analysis of the thermocouple data is outlined, along with a discussion of the calculated local flow properties that correspond to the transition events as identified in the flight data. The present analysis has confirmed that the boundary layer trips performed as expected for both flights, providing turbulent flow ahead of the inlet during critical portions of the trajectory, while the upper surface was laminar as predicted by the pre-flight analysis. Nomenclature