"Come Up And Get Me": Project Manhigh
The US Air Force's Project Manhigh was a pre-Space Age series of manned balloon flights to the very edge of space. They are considered to be the first steps ever taken towards true manned spaceflight. The flights aimed to answer questions regarding whether or not the human body could not only survive but function in the space environment, as well as what equipment would be necessary to send men into space and how future space capsules should be shaped. Despite being a military operation, it is the precursor to NASA's Project Mercury.
Manhigh II before launch taken by a spectator (stratocat.com)
By the 1950s, high altitude balloon flights were able to reach higher than 99% of Earth's atmosphere. They had one key advantage over rocket-powered high altitude research flights like those made by the X-15— duration. Manhigh's balloon gondolas could remain in the upper atmosphere for long periods of time for continuous experimentation and observation. The project tested equipment that would be necessary for future space missions, such as capsules, space suits, and telemetry and communications systems. More importantly, they tested human ability to function in the extreme environments of high altitude. Although two of the three flights took place before the Soviet Union launched Sputnik in October 1957, the US military already had its own goals of crewed spaceflight.
The Manhigh craft consisted of a gondola and a balloon. The gondola was constructed from aluminum alloy and was 8 feet (2.4 m) high and 3 feet (0.9 m) in diameter. It had hemispherically-shaped ends and resembled a pill capsule. This structure made it shock-absorbent during landing. Before launch, dry ice was put inside the top compartment to cool the cabin. The same gondola was used for all three flights and housed the pilot, equipment, experiments, and cameras. The sealed atmosphere was chemically treated to remove carbon dioxide and moisture. Its atmosphere consisted of oxygen, nitrogen, and helium. An open 40.4 foot (12.3 m) extended skirt parachute was attached to the top of the gondola and then attached to the balloon by a stabilizing suspension system that suppressed capsule oscillations during the flight. The balloon was made of polyethylene and increased in size per flight, the largest being 200 feet (61 m) wide. The pilot was in relative control of the balloon through an electrically driven fail-safe gas valve located at the bottom of the balloon that could be activated from inside the gondola. The entire craft weighed 2,166 pounds: 1,012 was the balloon, 598 was the gondola, 246 was the ballast, 70 were experiments, and 240 were the pilot, food, and equipment. Both the gondola and balloon were built by Winzen Research Inc., which was also responsible for pilot balloon training and launch support.
Cutaway diagram of the Manhigh balloon gondola (USAF)
Six unmanned test flights occurred before the first launch in the summer of 1957. Pilot training included parachute jumping, a 24-hour claustrophobia test inside the gondola, and ground tests using the capsule climate control system. That particular test took place in the high-altitude low-temperature test chamber at Wright Air Development Center (now known as Wright-Patterson Air Force Base) in Dayton, Ohio.
Manhigh I took place on June 2, 1957. It was flown by Captain Joseph Kittinger, who would later become famous for his high-altitude parachute jumps. He launched from Fleming Field Airport in St. Paul, Minnesota. The gondola reached an altitude of 95,000 feet (29 km) and remained there for two hours. Kittinger was unable to transmit voice communications during most of the flight due to a mechanical failure  so he relied on morse code. The mission was terminated early when he began to run out of liquid oxygen and inadvertently resulted in the most famous moment of the entire Manhigh project: Upon receiving orders from the ground to come down, the pilot unhappily replied in morse code, "Come up and get me." Kittinger landed in a small clearing in heavily wooded terrain. When the balloon was released at the instant of contact with land, the gondola toppled into the shallow water of a nearby creek.
Kittinger before the gondola was sealed (USAF)
Manhigh II took place on August 19, 1957 and was flown by Major David Simons. It reached a record-setting altitude of 101,516 feet (31 km) and remained in flight for 32 hours . It was a purely scientific mission and launched from Portsmouth Mine in Crosby, Minnesota. The cold internal temperatures caused Simons's fingers to become numb during the early hours of the flight so some objectives could not be completed. He became the first person to see a sunrise and a sunset from the top of Earth's atmosphere.
Manhigh III, the final flight, took place on October 8, 1958 and was flown by Lieutenant Clifton McClure. Unlike the previous two flights, it lifted off from Holloman Air Force Base in Alamogordo, New Mexico due to poor weather conditions in Minnesota. It was set to launch on October 7 but during inflation a gust of wind hit the balloon and destroyed it. The flight was rescheduled for the following morning with the only remaining balloon. Before launch while already inside the gondola, McClure accidentally pulled on the rope of his chest parachute and opened it. There was no replacement for it on the entire base so he decided not to tell anyone and with a great deal of patience packed it back in by hand. He also decided not to load dry ice into the upper compartment, which later on proved to be a very poor decision. Early during the flight McClure held a radio interview with a radio journalist and was supposed to visually track a missile launch from White Sands, but it never took place. Lack of dry ice and a failed cooling system caused the cabin temperature to reach the upper 90's and the pilot developed a fever— his body temperature peaked at 108.5°F (42.5°C) . Communications were lost when he dropped a photometer to the floor and it locked the gondola's transmitter foot switch. This meant he could receive ground transmissions but not deliver. To make sure the ground knew he was not incapacitated due to his fever, he turned on his beacon. The capsule landed in the dark a few miles from its launch site after roughly 12 hours of flight and a maximum altitude of 100,000 feet (30.5 km). McClure was hospitalized over night and miraculously did not suffer any damage from his fever.
Manhigh III expanded pilot requirements for high-altitude flights and included psychological, stress, and physical tests (such as riding in a centrifuge). These criteria were used later that year to select the world's first astronauts, those of the Air Force's Man In Space Soonest program (see "Hidden Histories: Man In Space Soonest"). They would also be further expanded upon by NASA to select its Mercury astronauts the following year.
Winzen looked into a fourth mission with a larger gondola and a flight duration of 5 days but it never came to be. Projects Excelsior and Stargazer were two other balloon missions that continued after Manhigh, but by the time they occurred NASA was progressing in spaceflight and not much attention was paid to them. Manhigh would go on to serve as the basis for Project Adam, the Army's pre-NASA proposal for manned suborbital spaceflight (see "Project Adam: or, How the US Could Have Beat the Soviets in Putting a Man Into Space").
Kittinger's Excelsior III jump in 1960 (public domain)
The Manhigh gondola is now on display at National Museum of the United States Air Force in Dayton, Ohio. Though not very well remembered by most, Project Manhigh paved the way for decades of crewed American spaceflight.
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 The failure was in the transmission's selector resulting in Kittinger being unable to determine the frequency to which the transceiver was tuned.
 A manned spaceflight that lasted that long would not take place until Vostok 3 in 1962.
 Hyperpyrexia is a body temperature exceeding 106°F (41.1°C).
Pacheco, Luis Eduardo. “MANHIGH I - (Kittinger).” MANHIGH I - (Kittinger) -1957-, stratocat.com.ar/fichas/1957/FMN-19570602.htm.
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Pacheco, Luis Eduardo. “MANHIGH III - (McClure).” MANHIGH III - (McClure) -1958-, stratocat.com.ar/fichas/1958/HMN-19581008.htm.
“Project Man High Gondola.” National Museum of the United States Air Force™, 14 Mar. 2016, www.nationalmuseum.af.mil/Visit/Museum-Exhibits/Fact-Sheets/Display/Article/196749/project-man-high-gondola/.
Swopes, Bryan. “Project Manhigh Archives.” This Day in Aviation, 8 Oct. 2020, www.thisdayinaviation.com/tag/project-manhigh/.