Project Mercury, a nationwide team effort led by NASA, recorded and studied the physiological and psychological effects of astronauts in space.

NASA selected McDonnell to design, develop and build the first crewed spacecraft Jan. 12, 1959. Before the final splashdown, May 16, 1963, McDonnell had delivered 20 vehicles, and the spacecraft had compiled 53 hours 55 minutes and 25 seconds of crewed space flight time.

Mercury set the trend for U.S. spacecraft design in the first decade. Its blunt end was covered by an ablative heat shield to protect against 3,000-degree re-entry heat.

Of the 20 Mercury vehicles delivered, six carried astronauts into space. On May 5, 1961, Alan Shepard, aboard a Mercury capsule, was the first American in space.