SR-71 Facts: 29 Details That Might Surprise You
The Airplane Grows 3-4 Inches at Altitude
Matter expands when hot, this is science. An aircraft is no different. Expansion Joints line the aircraft at strategic locations to allow the airframe to expand without causing damage to the plane. The SR-71 expands three to four inches in length during flight and the expansion gap in the image above can expand one to two inches as well. There are more expansion joints riddle throughout the airframe, but the one above is the most significant. As the SR-71 went into Supercruise, these expansion joints were absolutely necessary.