A standing shock wave is seen as a fine line leading outwards from the engine cowling of a 757-200. It was only visible where the background had varying horizontal contrast, and its position moved forward as the speed decreased during our descent. This picture is a shadowgraph.
The shock front is illustrated in the wiki diagram explaining supercritical airfoils, and may help you see the effect shown here.
Nice catch! Any guess on the conditions outside the plan when this occurred?
ReplyDeleteNothing particularly unique: airspeed was around 450mph, we were descending, and I think the effect is mostly independent of temperature.
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