For the space geeks out there, you know exactly what February 20, 1962 (and yes last week was the 51st anniversary of one of the greatest moments in U.S.A's spaceflight history) means in the annals of the US's spaceflight.
February 20, 1962 was the first time NASA had sent a manned craft into space with the intent of circling the globe. The capsule in question was Freedom 7 and the pilot (I know, stretching the pilot on a Mercury) was John Glenn.
But how many of you remember how close we came to losing Freedom 7 and Glenn on that same flight?
The flight play called for seven orbits but shortly after launch NASA noticed that Freedom 7's yaw thruster had malfunctioned which would mean that the mission would have to be drastically cut back.
Freedom 7's problems didn't end there. Almost immediately ground control received a warning that the "flotation ring " had been deployed. The ring was carefully stowed behind the heat shield and was only deployed after landing. The thruster pack is discarded during re-entry and the heat shield when atmosphere heating is no longer a problem. But when controllers discovered the floatation ring error, they knew this could only mean that the heat shield had partially or completely detached
This means that astronaut Glenn could perish on re-entry.
Since the thruster package still seemed intact and firmly attached, NASA decided to have Glenn fired a small de-orbit burn but do something unprecedented, leave the maneuvering pack still attached in hopes that if the heat shield was detached the pack would hold the shield in place.
Since a whole lot of things went right, John Glenn is still will us as are some very fortunet
There is a wealth of information on this flight at nasa and this report from the wiki
