Reading the other day about the time an A12 pilot used his undercarriage as air brakes to slow down from full speed.
The full speed of an A12 (codename Oxcart) was Mach 3.2. The plane was later developed into the more famous SR71 Blackbird.
Apparently the Lockheed engineer in the debrief room, on being told, snapped his pencil in surprise.
The pilot said it was “very loud”. I bet it was!