Mercury-Atlas 4 (MA-4) was an unmanned mission within the Mercury program, launched on September 13, 1961, at 14:09 UTC from Launch Complex 14 at Cape Canaveral, Florida. The spacecraft carried a Crewman Simulator instrument package. This flight marked the first successful orbital test of the Mercury program, as all prior successful launches had been suborbital. The payload included a pilot simulator to evaluate environmental controls, two voice tapes to assess the tracking network, a life support system, three cameras, and instruments to monitor noise, vibration, and radiation levels.
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| A MA-4 cover from "SpaceCraft", postmarked at Patrick Air Force Base on September 13, 1961. |
The MA-4 mission successfully met all its flight objectives. It demonstrated the Atlas LV-3B rocket's capability to launch the Mercury capsule into orbit and confirmed that the capsule and its systems could operate entirely autonomously, capturing images of the Earth in the process. However, to ensure safety and test additional design modifications, NASA planned one more unmanned test before proceeding with a crewed flight of the Mercury-Atlas combination.
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| Photo: The mechanical crewman simulator set up inside the Mercury capsule. |
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| Photo: A Mercury capsule is lifted to the top of Gantry 14 at Cape Canaveral to be positioned on an Atlas D missile. |
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| A MA-4 cover features a Swanson rubber stamp cachet and is postmarked at Patrick Air Force Base on September 13, 1961. |
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| Photo: A diagram illustrating the launch and recovery process of the MA-4 capsule. |
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| A MA-4 "Velvatone" cover postmarked at Port Canaveral on September 13, 1961. |
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| Photo: An automatic camera on board the unmanned Mercury spacecraft captured a section of the west coast of Africa during its orbit on Wednesday. The photo, released by NASA, was taken as the capsule traveled at 17,519 miles per hour, 110 miles above the Earth. |
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| Photo: Crewmen from USS Stephen Decatur recovering the MA-4 capsule. |
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| A crew cover from the USS Decatur, which was used for the recovery of MA-4, postmarked on September 13, 1961 and signed by Lt. J. A. Felt. |
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| Photo: The recovered MA-4 capsule was loaded onto an airplane for transport back to the United States. MA-4 capsule getting inspected after returned to Cape Canaveral on September 14, 1961. |
(Reference from
Mercury-Atlas 4)
