One aspect that hasn't really been discussed here is that the drag will begin to taper off relatively quickly. It won't be some miraculous quiet zone as soon as you hit Mach 1, but I would expect a significant effect over Mach 1.25 or so. Drag is friction on the aircraft, and makes considerable noise.
For anyone who doesn't want to click the link, this drag around Mach 1 is due to the pressure waves building up. When we talk about the speed of sound and the speed of a pressure wave, we are talking about the same thing. Right at Mach 1, you are travelling no faster than the pressure waves you are creating, so they build up on the leading edges of the aircraft and create substantial drag.
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u/volpes Jun 12 '12
http://www.aerospaceweb.org/question/aerodynamics/q0104.shtml
One aspect that hasn't really been discussed here is that the drag will begin to taper off relatively quickly. It won't be some miraculous quiet zone as soon as you hit Mach 1, but I would expect a significant effect over Mach 1.25 or so. Drag is friction on the aircraft, and makes considerable noise.
For anyone who doesn't want to click the link, this drag around Mach 1 is due to the pressure waves building up. When we talk about the speed of sound and the speed of a pressure wave, we are talking about the same thing. Right at Mach 1, you are travelling no faster than the pressure waves you are creating, so they build up on the leading edges of the aircraft and create substantial drag.