Ed.: Yes, that would probably be military aircraft doing training over the ocean, and sometimes their booms unintentionally reach land. The loudness of the booms is affected by humidity, humid air making the booms louder than dry air.
Hush: Do people in the planes hear them?
Ed.: No, not a boom sound, unless another supersonic aircraft flies by. We have flown supersonic aircraft in formation to measure the sonic booms. We had an F-16XL within 100 ft below an SR-71. The F-16XL pilot feels slow pressure changes on his helmet, but does not hear a boom. The normal booms we hear at NASA Dryden and Edwards Air Force Base are about 1-2 pounds per square foot. This is the pressure change you experience in going down a flight or two of stairs, but with a boom it happens in a few thousandths of a second. It is the rapid change of pressure in time that makes a boom. The pressure changes aren't very large. You need about 25 pounds per square foot of a sonic boom to break a house window.
https://www.nasa.gov/connect/chat/sonic_boom_chat.html
NASA nói rồi, phi công cái F 16 bay cách SR 71 100 ft lúc SRR71 vượt âm chả nghe thấy gì và chỉ cảm thấy thay đổi áp suất trong mũ trùm đầu.
