Gemini 9 EVA
During the Gemini 9 EVA in 1966, handrails, Velcro pads, and foot restraints failed to help astronaut Gene Cernan control his movements. In Walking to Olympus: An EVA Chronology, authors David S.F. Portree and Robert C. Trevino noted that Cernan spent half his time outside the capsule just maintaining his position. “As he struggled, he broke off an experimental antenna mounted on Gemini 9 and tore the outer layers of his suit…. After returning to Earth, Cernan conducted underwater neutral buoyancy simulations of his EVA in the Weightless Immersion Facility pool…. He reported that neutral buoyancy simulation nearly duplicated actual EVA conditions, helping to validate it as an EVA training tool.”
By the time Cernan returned to space, as the lunar module pilot of Apollo 10, underwater simulations were the norm. Nor was that the astronauts’ only water training. In this image from August 1968, he and crewmate John Young (in the raft) exit their Apollo Command Module trainer—practice for an ocean splashdown.