The Project Mercury helicopter recovery team transports NASA Astronaut Alan Shepard and his spacecraft to the U.S. Navy Carrier Champlain following the first suborbital Mercury flight.
Astronaut John Glenn enters the Friendship 7 and prepares for launch. He becomes the first American to orbit the earth.
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One of the first steps toward going to the moon was taken well before the goal was ever officially established. On Oct. 7, 1958, the United States initiated the first national manned space flight project, later named Project Mercury.
The life of Project Mercury was about 4 2/3 years, from the time of its official go-ahead to the completion of the 34-h orbital mission of astronaut Gordon Cooper. During this period, much was learned about an astronaut's capabilities in the space environment and in earthbound activities. This enabled the successful accomplishment of the program objectives in a relatively short time.
The spacecraft used in Project Mercury was a capsule that accommodated a crew of one. Two launch vehicles were used for the manned program — the Redstone and the Atlas. The Redstone was used for the first two manned suborbital missions. However, it did not posses the power to place the Mercury spacecraft into orbit. Therefore the Atlas vehicle was used for the remainder of the missions in Project Mercury.
The first manned mission of the project, Mercury 3, occurred on May 5, 1961, and made Alan Shepard the first American in space. This suborbital flight, which lasted 15 min., 28 s, demonstrated adequate propulsion, vehicle control, space systems, pilot capabilities in space, in-flight monitoring, retrofire and reentry maneuvers, landing, and recovery. The Freedom 7 spacecraft flew to an altitude of 116.5 statute mi and at a velocity of 5134 mph.
Following the success of the mission, President Kennedy announced the nation's commitment to achieving the goal of placing an American on the moon. "First, I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the moon and returning him safely to the Earth," he declared before a joint session of Congress on May 25, 1961. "No single space project in this period will be more impressive to mankind, or more important for the long-range exploration of space; and none will be so difficult or expensive to accomplish." This aggressive goal and schedule led to the space program's step-by-step approach of developing the necessary skills and technology to attempt such an undertaking.
The next Mercury mission, flown by astronaut Gus Grissom, was to demonstrate the changes made to the Mercury spacecraft such as the addition of a large viewing window and an explosively actuated side hatch. After flying to an altitude of 118.3 statute miles, the Liberty Bell 7 spacecraft reentered the atmosphere and splashed down 302 miles East of the launch site. The spacecraft sank shortly after splashdown due to premature actuation of the explosive bolts that release the side hatch. Grissom was successfully recovered.
To achieve the next goal of Project Mercury, astronaut John Glenn had to travel atop a modified ballistic missile called Atlas. It was the first time this missile was used as a launch vehicle. Mercury 6's objective was to place a person into earth orbit, observe his reactions to the space environment, and safely return him to earth to a point where he could easily be recovered. On Feb. 20, 1962, Glenn became the first American to orbit the earth in his Friendship 7 capsule.
Glenn achieved three successful orbits before having to cut his trip short because of two malfunctions. The first problem encountered was a clogged yaw attitude control jet, which forced the astronaut to abandon the automatic control system for the manual-electrical fly-by-wire system. Another concern was a faulty switch in the heat shield circuit indicating that the clamp holding the shield had prematurely released. This caused Glenn to leave the retropack attached to the craft to help hold the heat shield in place in the event that it had loosened. If the heat shield became detached or was out of position, the spacecraft would have burned up during reentry. Because of the communications blackout that occurs during reentry, nobody knew whether the heat shield remained in place until just before splash-down. Friendship 7 landed safely 800 miles southeast of Bermuda.
Aurora 7 followed with three orbits of its own during the Mercury 7 mission. The only mission-critical malfunction that occurred involved a failure in the spacecraft pitch horizon scanner, a component of the automatic control system. The pilot, Scott Carpenter, in subsequent in-flight operations adequately compensated for this anomaly so that the success of the mission was not compromised. A modification of the spacecraft control-system thrust units was effective. Cabin and pressure suit temperatures were high, but not intolerable.
The Sigma 7 spacecraft, flown by astronaut Walter Schirra, achieved six orbits during the Mercury 8 mission. This mission further studied astronauts' capabilities for longer periods of weightlessness. Schirra spent a total of 8 h, 56 min. in a weightless environment.
Astronaut Gordon Cooper spent an even longer time in a weightless environment during his one-day mission. His Faith 7 spacecraft made a total of 22 orbits at an altitude of 165.9 by 100.3 statute mi.
Project Mercury validated the technology developed for placing people into space and in orbit around the earth. This represented the first step in going to the moon as well as the foundation for further spacecraft design and development in the Gemini and Apollo programs.
