DRAG MEASUREMENTS AT MACH-5 USING A STRESS WAVE FORCE BALANCE

The stress wave force balance, which has been used for measurements of drag on short models in hypersonic impulse facilities, is investigate d here for its suitability for drag measurements on a longer, axisymme tric model. The sensitivity of the balance to loading distribution is investigated and results are reported for experiments on a 5 degrees s emi-angle cone, 425 mm in length and of 1.71 kg mass. Experimental dra g measurements are shown to be in good agreement with theoretical leve ls. An investigation into the period over which the stress wave force balance can be used is addressed and, for the present model, the balan ce is shown to be suitable for measurements in flows of durations of o ne to several milliseconds with an estimated accuracy of +/- 10%.