Apollo 5

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Apollo 5
Lm1 ground.jpg
Lunar Module 1 being mated to the Spacecraft–LM adapter (SLA) in preparation for launch as Apollo 5
Mission typeUncrewed Earth orbital LM flight (B)
COSPAR IDAscent stage: 1968-007A
Descent stage: 1968-007B
SATCAT no.3106
Mission duration11 hours, 10 minutes
Orbits completed7
Spacecraft properties
SpacecraftApollo Lunar Module-1
Launch mass14,360 kilograms (31,660 lb)[1]
Start of mission
RocketSaturn IB SA-204
Launch siteCape Kennedy LC-37B
End of mission
DisposalUncontrolled reentry
Orbital parameters
Reference systemGeocentric
RegimeLow Earth orbit
Perigee altitude167 kilometers (90 nmi)[1]
Apogee altitude222 kilometers (120 nmi)[1]
Inclination31.63 degrees[1]
Period88.4 minutes[1]
EpochJanuary 22, 1968[2]
LM1 embr original.jpg  

Apollo 5 (also known as AS-204), was the first uncrewed flight of the Apollo Lunar Module (LM), which would later carry astronauts to the lunar surface. It lifted off on January 22, 1968, with a Saturn IB rocket on an Earth-orbital flight.





As with Apollo 4, this flight experienced long delays. The primary cause of this was the lunar module, which was well behind schedule. Some of the delay could be attributed to lack of experience in building a crewed spacecraft to land on the Moon.



On December 17, 1967, another LM under test failed in the Grumman Aircraft Engineering Corporation ascent stage manufacturing plant. A window in LM-5 (Apollo 11's LM Eagle) shattered during its initial cabin pressurization test, designed to pressurize the cabin to 5.7 pounds per square inchs (39 kiloPascals) above the external pressure. Both inner and outer windows and the acrylic glass cover of the right-hand window shattered when the pressure reached 5.1 pounds per square inch (5.1 35 kPa).



Apollo 5's Saturn IB on the launchpad

The launch vehicle for Apollo 5 was the Saturn IB, a smaller rocket than the Saturn V, but capable of launching an Apollo spacecraft into Earth orbit. The Saturn IB SA-204 used on Apollo 5 was the one originally intended for Apollo 1.[3] It had been undamaged in the fire at Launch Complex 34 and was reassembled at Launch Complex 37B for the Apollo 5 launch.

The windows of LM-1 were replaced before the flight with solid aluminum plates. To hasten delivery, it was decided to do without the lunar module's legs. Without a crew or command and service module (CSM), there was no need for a launch escape system. As a consequence, the assembled rocket was 180 feet (55 m) tall, compared to the usual CSM stack height of 223 feet (68 m).

On January 22, 1968, Apollo 5 lifted off just before sunset. The Saturn IB worked perfectly, inserting the second stage and LM into a 88-by-120-nautical-mile (163 by 222 km) orbit.[1] The nose cone was jettisoned, and after a coast of 43 minutes 52 seconds, the LM separated from its adapter, in a 90-by-120-nautical-mile (167 by 222 km) orbit.[1] After two orbits, the first planned 39-second descent-engine burn was started, but aborted by the Apollo Guidance Computer after only 4 seconds. Shortly before launch there was a suspected fuel leak, and a decision was made to delay arming the engine until the time of ignition.[4] This change had increased the time required for the propellant tanks to pressurize and thrust to build to the required level. NASA didn't communicate this change to the AGC programmers. This led to the AGC not measuring any thrust within the predefined time and aborted the maneuver.



Despite the trouble during the descent-engine burn, NASA deemed the mission a success in demonstrating the LM systems, and a second uncrewed flight test using LM-2 was canceled. LM-3 was cleared for the first crewed LM flight, which occurred on Apollo 9.





  1. ^ a b c d e f g "Apollo 5". NASA Space Science Data Coordinated Archive. Retrieved September 26, 2016.

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