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Overview

Surprised by the Soviet Union’s successful Vostok mission, the US needed a success. It came in the form of Project Mercury. These missions served as the Vostok program’s equal; they were designed to carry Americans into the final frontier. In this article, I’ll be discussing Mercury-Redstone 3, better known as Freedom 7, the first manned mission of Project Mercury. Freedom 7 launched from Cape Canaveral on May 5, 1961. A modified missile carried Alan Shepard onto a sub-orbital trajectory, and the capsule splashed down in the Atlantic Ocean after 15 minutes 28 seconds.

Mission Details

Freedom 7 utilized the Mercury-Redstone Launch Vehicle, a modified version of the Jupiter-C first stage. Based on the standard Redstone missile, the Jupiter-C was equipped with longer fuel tanks; as a result, it was better suited to carrying heavier payloads. Engineers chose the Rocketdyne A-7 to power the craft. They also opted for an ethanol-water mix over the Jupiter-C’s hydyne fuel, as hydyne’s toxicity outweighed its benefits on a manned mission. Other measures were put in place to ensure astronaut safety. The rocket was equipped with an abort sensing system, which would trigger the escape tower if it detected a potential failure. Triggers included such conditions as low pressure in the engine’s combustion chamber, loss of electrical power, and large deviance from the preset flight plan. Engineers opted for the LEV-3 autopilot system over the Jupiter-C’s ST-80. Sacrificing refinement for reliability, the LEV-3 originally served as the guidance system for the German V-2. All critical systems were stored in a cooled compartment to ensure maximum reliability.

After several countdown halts due to weather conditions, a malfunctioning power inverter, and computer errors, Freedom 7 launched from Cape Canaveral Air Force Station at 9:34 AM EST. The A-7 engine, providing 357 kN of thrust, burned for 144 seconds before detaching; it had accelerated the craft to 5134 miles per hour (2295 m/s), with a peak g load of 6.3. After separation, Shepard coasted to an apogee of 116.5 miles (187.5 kilometers), becoming the first American in space. He then disabled automatic attitude control and manually oriented the craft for re-entry using the on-board hydrogen peroxide jets. Shortly after, the retrorockets fired. As the craft re-entered, Shepard experienced a peak g load of 11.6. The capsule’s drogue chute deployed at 21000 feet (6400 meters), and the main chute was released at 10000 feet (3048 meters) above sea level. Falling at a rate of 35 feet per second (10.6 m/s), Freedom 7 splashed down at 9:49 AM EST.

Historical Significance

For the US, Freedom 7 made up important ground in the Space Race. Although Yuri Gagarin beat Shepard to be the first man in space, Freedom 7 established that the US was comparable to the Soviet Union in terms of spaceflight. It strengthened national pride and reduced doubts about American technology. Additionally, Freedom 7 holds an important title in US space history. As the first manned US spaceflight, it marked the beginning of a new era for the US. Freedom 7, along with the other Mercury missions, paved the way for future American space ventures, including such programs as Gemini and Apollo.

Freedom 7 also provided scientific insight as to the practicality of manned spaceflight. Before the Mercury missions, a cloud of doubt surrounded human capabilities in the weightless environment of space. Doctors predicted that astronauts would return disoriented; psychologists expected men to become mentally unstable. Shepard dispelled these fears when he returned to Earth safe and sane. He also proved the feasibility of manual control in space though his successful orientation maneuvers.

Conclusion

Freedom 7 remains one of the most significant spacecrafts in US history. It established America as a worthy contender to the Soviet Union and sparked a decade of spaceflight which culminated in the Apollo moon landings.

Rating: ★★★★☆