Mercury

The Mercury spacecraft's principal designer was Maxime Faget, who started research for manned spaceflight during the time of the NACA. With 100 cubic feet (2.8 m3) of habitable volume, the capsule was just large enough for a single crew member. Inside were 120 controls: 55 electrical switches, 30 fuses and 35 mechanical levers. The heaviest spacecraft, Mercury-Atlas 9, weighed 3,000 pounds (1,400 kg) fully loaded. Its outer skin was made of René 41, a nickel alloy able to withstand high temperatures.