Contents

AS-203: Difference between revisions

Revision as of 00:43, 17 April 2010

This article's lead section may be too short to adequately summarize the key points. Please consider expanding the lead to provide an accessible overview of all important aspects of the article. (October 2009)

AS-203

Mission Insignia
Mission statistics
Mission name:	Apollo-Saturn 203
Call sign:	AS-203
Launch:	July 5, 1966 14:53:13 UTC Cape Canaveral Complex 37B
Destroyed:	July 5, 1966 ~20:53:00 UTC
Duration:	~6 hours
Number of orbits:	4
Apogee:	131.7 mi (212 km)
Perigee:	113.7 mi (183 km)
Period:	88.5 min
Inclination	31.94 deg
Distance traveled:	100,583 mi (161,872 km)
Apogee mass:	26,552 kg
AS-203

AS-203 (orSA-203) was an unmanned flight Saturn IB launch vehicle. It is sometimes informally called Apollo 2.

Objectives

The main purpose of the AS-203 flight was to investigate the effects of weightlessness on the fuel in the S-IVB tank. The reason for this was that the S-IVB would be used by Apollo astronauts to boost them from Earth orbit to a trajectory towards the moon. Engineers wanted to see what the liquid hydrogen would do in the tank - settle in one place or maybe even slosh violently. The S-IVB tank was equipped with 83 sensors and two TV cameras to record what the fuel did in the tank.

Because this was an engineering flight, there was no Command Service Module (CSM). This was also the first flight of a new type of Instrument Unit that controlled the Saturn rockets during launch and the first launch of a Saturn IB from Pad 37B.

Preparation

In the spring of 1966, the decision was made to launch AS-203 before AS-202, as the CSM that was to be flown on AS-202 was delayed. The S-IVB stage arrived at the Cape on 6 April 1966; the S-IB first stage arrived six days later, and the Instrument Unit came two days after that.

On April 19, technicians began to erect the booster at Pad 37B. Once again, the testing regime ran into problems that had plagued AS-201, including cracked solder joints in the printed-circuit boards, requiring over 8,000 to be replaced.

In June 1966, three Saturn rockets could be seen set up on various pads across the Cape: at Pad 39A was a full-size mock-up of the Saturn V; AS-202 was at Pad 34; and AS-203 was at 37B.

Flight

The rocket launched on the first attempt on July 5. The S-IVB and IU were inserted into a 188 km circular orbit.

It was found that the stage could restart and that the fuel behaved just as predicted. It was observed over four orbits and then the stage was pressurized to see how much stress it could stand. In the end this test exceeded the structural capabilities of the stage and it fragmented.

Despite the destruction of the stage, the mission was classified as a success, having achieved all of the mission objectives. In September Douglas Aircraft Company, who built the S-IVB, declared that the stage was operational and ready to send men to the Moon. Fragments of the first stage supposedly hit a German fishing vessel.

External links

• Evaluation of AS-203 Low Gravity Orbital Experiment - Jan 1967 - NASA (PDF format)
• http://nssdc.gsfc.nasa.gov/database/MasterCatalog?sc=1966-059A
• Moonport: A History of Apollo Launch Facilities and Operations
• Chariots for Apollo: A History of Manned Lunar Spacecraft