On March 24, 1961, NASA's Mercury Redstone rocket launched on its last uncrewed flight before it started sending astronauts into space. The mission was known as the Mercury Redstone Booster Development flight, and it wasn't originally planned as part of the Mercury Program. The previous Mercury Redstone flight carried a chimpanzee named Ham into space. Ham made it back alive, but the rocket had several issues during the flight. So, NASA made some changes to the design and tested it one more time

MR-1: The Four-Inch Flight 65 years ago today, the first attempt to launch a Mercury capsule on a Redstone rocket (MR-1) took place. Unfortunately, a fault in the ground equipment caused the engines to shut down shortly after firing, lifting the vehicle four inches off the ground before it settled back down on the launch pad. The capsule's escape rocket was activated, causing it to jettison itself and triggering the spacecraft's parachutes to deploy. NASA launched its first astronaut to space ab