An exact method is developed for determining the total (static plus dynamic) aerodynamic forces and moments experienced by a body free-flying in a wind tunnel from measured accelerations. These accelerations are measured onboard and are telemetered to stationary receivers outside the wind tunnel. An approximate method is presented for separating the total forces and moments into their familiar static and dynamic components. Approximate analytic equations are derived for expressing the errors in various quantities in terms of measurement uncertainties. Results from these equations are compared with those from exact numerical calculations and agreement is satisfactory. An experiment with a 20° half-angle conical model at a nominal Mach number of 1.9 in the Ames 6- by 6-ft wind tunnel, in which time histories of two normal and two axial accelerations were measured simultaneously, is discussed. Problems encountered during the course of the experiment precluded a complete assessment of this testing technique, but sufficient data of good quality were obtained to allow a linearized data reduction scheme to be applied. Most of the results obtained from this method compared favorably with those measured previously in a more conventional manner with a sting-mounted model.
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