system
Given the following post, respond as if you're commenting on Reddit:
human
Did scientists know that there was going to be a loud *BOOM* before they first broke the sound barrier?

Just a random thought I had last night. Did they suspect that there would be a specific indication of when they reached 343.2 m/sec?
gpt
First off, the sound speed in air isn't so precise. It can vary by +/-10 m/s based on temperature alone.

Second, they knew that the pressure would build up in front of the plane, that the build up of pressure would eventually form a shockwave, and that the shockwave formed would sound like "boom." It's hard to say what people close to the problem knew, but there seems to have been some discussion about what forces would act on the plane at that moment, and whether it would get ripped apart by them.

Incidentally, the first manmade sonic boom likely came from the snapping of a bullwhip moving faster than the speed of sound. This probably gave scientists something of an understanding of how a sonic boom would behave.