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Say you're an astronaut on a ride to the ISS, and you have with you a very accurate clock, an automatic pressure sensor, and a high quality microphone.

If you synchronized the sensor and microphone with the clock (taking measurements with the computers for resolution), would the amplitudes of the two signals be maximized at the same point in time?

If not that, what about "roughest" part of the flight (where the aircraft is shaking the most from colliding with the atmosphere)?

ijustlovemath
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    Roughest depends on the vehicle characteristics. The SRB part of the shuttle ride was rough; Falcon 9 doesn't have those. Sound probably does too. – Organic Marble Feb 19 '24 at 03:37
  • If you're an expert on one vehicle in particular, feel free to post an answer! – ijustlovemath Feb 19 '24 at 03:42
  • Completely irrelevant nitpick: As an astronaut on a ride to the ISS, you're not going to be able to measure the dynamic pressure ("Q"). To do that, you would have to attach your pressure sensor to the nose of the vehicle, which you will probably find fairly hard to do for a multitude of reasons. – TooTea Feb 21 '24 at 13:52
  • I didn't specify where the sensors are located, but of course they would not be in the cabin with the astronaut. Also, this is a thought experiment! – ijustlovemath Feb 21 '24 at 14:00
  • @TooTea you are correct, it's not measured: https://space.stackexchange.com/a/49480/6944 – Organic Marble Feb 21 '24 at 14:48

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While I'm not sure if loudness correlates well with roughness, I did find a study that correlates roughness (vibrations) with Max-Q. The study describes the source of roughness as thrust oscillations, rough combustion, and pogo oscillations as opposed to aerodynamic effects that might peak at maximum dynamic pressure.

According to the study, the Space Shuttle launch (~10 seconds post lift-off) was the highest vibration phase. Interestingly, they did say on page 21 that Max-Q (~50 seconds post lift-off) was the time of second highest vibration during the ascent of flight.

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phil1008
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