Mercury 6

John Glenn, Jr., as he enters into the spacecraft (NASA)
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The Mercury 6 mission was one of the Mercury program manned space missions. It was launched on February 20, 1962, and the Mercury capsule was named "Friendship 7". It made three earth orbits, piloted by astronaut John Glenn, the first American to orbit the Earth.

Before reentry, a warning light indicated that the heat shield may have detached - a problem with potentially fatal consequences. A decision was made to keep the retro-rockets attached during reentry in the hope their mounting straps would help keep the shield in place. Reentry was uneventful, and the warning light problem was determined to be a faulty switch.