Mercury Manned Flights

The Escape Tower

Many people are not sure what purpose of the tall tower attached to the top of rocket above the capsule. During the early days of the space program, rocket failures were all too common and the rockets had to be aborted / destroyed at or soon after liftoff. When we first began the process of putting men on top of these ballistic missiles, it was important to provide a means of escape if a missile abort was required.

Once the astronaut was secured in his spacecraft, the escape tower was activated and could be initiated at any time if a problem occurred. The system was designed to shut down the main engine immediately, ignite secondary rocket engines at the top of the tower while at the same time disengaging the clamps holding the capsule to the rocket. The secondary rocket engines would then provide enough thrust to safely lift the capsule away from the main rocket until it reached a high enough altitude where the capsules parachute could be safely deployed for return to Earth.

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ABOVE NASA PHOTO: Mercury-Redstone rocket taking off from Cape Canaveral, May 5, 1961 with Alan Shepard at the controls.

Mercury Space Program

On May 5, 1961 America officially entered the manned space program when at 9:34 a.m. NASA controllers "lit the candle" and sent Mercury astronaut Alan Shepard arcing into space atop a Redstone rocket.

The flight of Freedom 7 - the first space flight by an American - followed just a month after Soviet Cosmonaut Yuri Gagarin became the first into space.

Shepard's 15 minute sub-orbital flight achieved an altitude of 116 miles and a maximum speed of 5,134 miles per hour. As Shepard looked back near the peak of Freedom 7's trajectory, he could see the Gulf of Mexico, the outline of Florida's west coast, Lake Okeechobee, and the Bahamas.

The Mercury Spacecraft

By any standards, the Mercury spacecraft were small. In all they were just a little over 11' tall. The astronauts who piloted them were test pilots used to having complete control over their test flights, but with the Mercury capsules, they were mostly along for the ride. America's top test pilot, Chuck Yeager, described the astronauts flying the capsules as "spam in a can" because they were originally just so much meat inside a big can. However, the astronauts eventually gained some controls over their flying machines. They petitioned for a larger window so they could see where they were going. They also succeeded in getting manual re-entry controls which would eventually prove to be a major step forward and a life-saving improvement.

The beginning of America's manned space program had 7 astronauts:

• Alan Bartlett Shepard, Jr. / Mercury-Redstone / FREEDOM 7

• Virgil Ivan "Gus" Grissom / Mercury-Redstone / LIBERTY BELL 7

• John Herschel Glenn, Jr. / Mercury-Atlas / FRIENDSHIP 7

• Malcolm Scott Carpenter / Mercury-Atlas / AURORA 7

• Walter Marty "Wally" Schirra, Jr. / Mercury-Atlas / SIGMA 7

• Leroy Gordon "Gordo" Cooper, Jr. / Mercury-Atlas / FAITH 7

• Donald Kent "Deke" Slayton / Slayton was grounded for an irregular heart beat, but later flew on an Apollo test flight.

Each of these astronauts named their own spacecraft and added the number "7" to acknowledge the teamwork involved in the entire project.

The Mercury Program was designed to see if man could survive and function during a space flight experience. How would man react during the stress of liftoff, weightless flight, re-entering the atmosphere and being able to survive a landing. Although a Soviet Cosmonaut had already tested the success of these objectives, it was determined that the United States to conduct its own testing.

The Mercury-Redstone Program was originally scheduled for 8 flight tests. However, only 6 of the planned flights were attempted including 2 manned flights. The success of the program warranted the cancellation of the last 2 planned flights.

After Alan Shepherd's flight in May 1961, the second American in space Astronaut Virgil "Gus" Grissom, was successfully launched aboard Flight MR-4 in July of that year. With that mission's success, the Mercury-Redstone Program was phased out in September and was replaced by the Mercury-Atlas Program that put John Glenn into space as the first American to orbit the Earth.