Aero-optical environment around a hemisphere-on-cylinder turret with both flat- and conformal windows was studied experimentally in-flight using AAOL-T for a range of subsonic and transonic Mach numbers between 0.5 and 0.8. Above M = 0.6, the local shock appeared near the top of the turret, causing additional aero-optical distortions at side-looking angles. The shock dynamics was extracted from instantaneous wavefronts and analyzed in details. The mean shock location was found be near α = 80 degrees for both window types at M = 0.7 and 0.8. For M = 0.7, the shock motion exhibits multiple-harmonic behavior between St_D = 0.15 and 0.8, while for M = 0.8, the shock has a lower single frequency peak at St_D = 0.15, the same as for the unsteady separation line, indicating a possible lock-in mechanism between the shock and the separation region at high transonic Mach numbers.
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