The reconstructed MA-1 spacecraft after debris recovery
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Mission type | Test flight |
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Operator | NASA |
Mission duration | 3 minutes, 18 seconds Launch failure |
Distance travelled | 9.7 kilometres (6 mi) |
Apogee | 13.0 kilometres (8.1 mi) |
Spacecraft properties | |
Spacecraft | Mercury No.4 |
Manufacturer | McDonnell Aircraft |
Launch mass | 1,154 kilograms (2,544 lb) |
Start of mission | |
Launch date | July 29, 1960, 13:13 | UTC
Rocket | Atlas LV-3B 50-D |
Launch site | Cape Canaveral LC-14 |
Project Mercury
Mercury-Atlas series |
Mercury-Atlas 1 (MA-1) was the first launch attempt of a Mercury capsule (not including the boilerplate spacecraft of the September 1959 Big Joe flight) launched at 13:13 UTC on July 29, 1960 from Cape Canaveral, Florida. The Mercury spacecraft was unmanned and carried no launch escape system. The mission was to conduct a suborbital test flight and reentry of the spacecraft. The capsule had live posigrade separation rockets, but dummy retrorockets. Several other systems were missing including the cabin pressurization system and the astronaut couch. The ASIS abort system was flown for the first time on MA-1 in open-loop mode, meaning that the booster portion was present, but not the capsule portion.
The Atlas rocket suffered a structural failure 58 seconds after launch. The vehicle at that time was at approximately an altitude of 30,000 feet (9.1 km) and 11,000 feet (3.4 km) down range when it was passing through Max Q and all telemetry signals suddenly ceased. Because the day was rainy and overcast with thick clouds, the booster had been out of sight from T+26 seconds and it was impossible to see what happened. A number of Mercury engineers had voiced their objection to launching on July 29 because of the weather precluding visual coverage of the flight. Some observers claim to have heard an explosion, but this could not be verified. The capsule continued transmitting until it impacted the ocean, approximately 6 miles downrange. Subsequent salvage attempts dredged it and the Atlas's booster engines and LOX vent valve from the ocean floor. The booster engines showed no sign of damage except some deformation from impact with the ocean, but the vent valve and a still-attached segment of piping had noticeable fatigue cracks.
Telemetry indicated that the Atlas functioned normally up to T+58 seconds and there was no sign of any problems up to that point, when a severe axial disturbance was detected. Approximately one second later, the pressure difference between the RP-1 and LOX tanks dropped to zero followed by loss of engine thrust and telemetry and the appearance of multiple objects on radar. Capsule data indicated violent movements following loss of booster telemetry, but the Mercury otherwise continued functioning normally until impact with the ocean at around 220 seconds after launch. The automatic abort system appeared to have functioned correctly and issued a shutdown command to the Atlas's engines the moment that it detected an abnormal situation. The parachute system did not deploy because the abort had taken place too early in the launch.