Lockheed engineers designed the SR-71 Blackbird spy plane with titanium body panels that fit together so loosely on the ground that the aircraft actively leaked jet fuel all over the runway before takeoff.

A closer look

Lockheed engineers designed the SR-71 Blackbird spy plane with titanium body panels that fit together so loosely on the ground that the aircraft actively leaked jet fuel all over the runway before takeoff. This was not a manufacturing defect but a necessary design choice because flying at three times the speed of sound generates so much friction that the metal plates would expand and seal the gaps mid-flight. It is basically the aerospace equivalent of wearing sweatpants to a buffet so you have room to expand after eating six plates of crab legs. The military literally had to invent a special high-flashpoint fuel just so the leaking puddles wouldn't accidentally incinerate their multi-million dollar top-secret reconnaissance asset before it even left the tarmac. We spent billions of taxpayer dollars to defeat the Soviets using a revolutionary jet that essentially peed itself in front of everyone right before performing the most badass aerial maneuvers in history