Apollo 5

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Apollo 5
Mission Insignia
File:LM1 embr original.jpg
LM-1 Insignia
Mission Statistics
Mission Name: Apollo 5
Call Sign: AS-204
Launch: January 22, 1968
22:48:09 UTC
Cape Canaveral
Complex 37B
End of
Mission:
January 23, 1968
~09:58:00 UTC
Duration: 11 h 10 min
Number of
Orbits:
7.5
Apogee: 133 mi (214 km)
Perigee: 100.7 mi (162 km)
Period: 89.5 min
Inclination 31.6 deg
Distance
Traveled:
~190,000 mi
(300,000 km)
Mass: 14,360 kg
AS-204

Apollo 5 was the first unmanned flight of the Apollo Lunar Module that landed man on the Moon.

Objectives

This was the first flight of the Lunar Module and as such was basically a systems test. This would be the first firings of the descent and ascent engines in space. The descent engine was also the first throttleable rocket engine fired in space.

Also there would be a 'fire in the hole' test where the ascent engine was fired while still attached to the descent stage. This would simulate the conditions experienced during an abort during descent to the lunar surface.

Delays

Lunar Module 1
Lunar Module 1 during ground testing

As with Apollo 4, this flight experienced long delays. The primary cause of this was the Lunar Module. It was well behind schedule, though of course schedules are based on previous experience and nobody had ever built a manned spacecraft to land on the moon.

It had been planned to launch Apollo 5 in April 1967 and so delivery at the Cape was hoped for around September 1966. But delays kept occurring. Although the lunar module was fully designed, there was trouble fabricating the custom made parts. The all important engines were also having problems. The descent engine was not burning smoothly and the ascent engine was having fabrication and welding difficulties.

In the end these problems were overcome but it took several months and it wasn't until 23 June 1967 that the Lunar Module arrived at the Cape onboard Aero Spacelines' Super Guppy. After four months of tests and repair the Lunar Module was mated to the launch vehicle on 19 November.

Flight

Saturn Ib on the launchpad
Apollo 5 on the Saturn Ib

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 that was used on Apollo 5 was the one originally intended for Apollo 1. It was undamaged in the fire that killed the crew and so it was decided to reuse it.

LM-1 lacked one important thing for a lunar landing - legs. It had been decided that to shorten the delivery time for the Lunar Module that the first test flight would not have legs. There was no need for them in Earth orbit though there was a feeling around NASA that the fewer versions of a spacecraft created the better. The rocket also didn't feature a launch escape system, meaning it was only 55 metres tall.

Finally on January 22, 1968, eight months after the planned launch date, Apollo 5 lifted off just before sunset. The Saturn IB worked perfectly, inserting the second stage and LM into a 163 x 222 km orbit. The Lunar Module separated 45 minutes later and then two orbits later started a planned 39 second burn of its descent engine. This lasted for only 4 seconds however, after the guidance computer detected the spacecraft was not travelling fast enough. The cause was that the propellant tanks were only partially pressurised and it took longer than the programmed four second to reach full acceleration.

The ground controllers decided to move to an alternate plan. They turned off the guidance computer and started an automatic sequence programmed into the onboard computer. This fired the descent engine two more times. It then performed the fire-in-the-hole test and another ascent engine burn.

After four orbits the mission was over and the two stages were left to decay on into the Pacific several hundred kilometers southwest of Guam on 12 February.

The Apollo 5 LM ascent stage (1968-007A) decayed January 24, 1968. The LM descent stage (1968-007B) decayed February 12, 1968.

Insignia

This patch was not designed by NASA but by the engineers at Grumman Aircraft who designed and built the Lunar Module. It portrays the fire-in-the-hole test. It also shows the LM without landing gear and with the moon in the top right.



Preceded by :
Apollo 4
Apollo program Followed by :
Apollo 6