BY admin | November 17, 2012
NASA’s powerful Saturn V moon rocket launch was simply fascinating and inspiring for the people not just in USA, but across the world
When people fantasize about futuristic rockets that can travel space as easily as a boat travels though water, they hardly understand the complexities of building a working rocket. The transition is like going from dreaming of a flying carpet to building the functional plane, that hulking mass of metal that can not only fly itself but take hundreds of people with it. In the process you add messy details like fuel, a runway, a host of high technology, right wingspan constructed with suitably light and durable material and the possibility that the whole thing might explode in a giant fireball.
Something similar happens when you try to translate a fantasy like the Enterprise (the Star Trek starship) into a functional rocket that can take people to space. When NASA first started to build its rockets, it had a hard deadline to adhere to. President Kennedy had announced that the US will put a man on the moon within a decade; and the decade was nearing its end.
The problem was that a rocket which can take people to the moon is fiendishly difficult to build. It has multiple parts which need to be tested separately, because, if any one of them malfunctions it could cause the entire rocket to explode right there on the Launchpad.
An explosion on the Launchpad was not to be taken lightly. A rocket of the size to get to the moon has enormous amounts of fuel which could cause an explosion that would shoot a fires over a 1000 ft in diameter which could continue to burn for nearly half a minute.
NASA was testing the Saturn V for its manned mission. The Saturn V stood 363 ft tall and had a maximum thrust at launch of 7.5 million pounds. In the first stage itself the rocket burned fuel at the rate of 15 tons per second, and would burn a total of 4.5 million pounds of propellant — liquid oxygen and RP-1 or kerosene.
Were this to explode, it would cause a fireball 1,408 feet in diameter and burn for 33.9 seconds at a peak temperature of 2,500 degrees Fahrenheit. Given the risks it was prudent to test each part separately until they worked perfectly and then continue adding parts, and testing them. So that when the final prototype was ready, it had already been tested several times over, just not together.
This was the approach favoured by Wernher von Braun and the German engineering team who had built the successful Jupiter series. NASA started development of the Saturn V in Jan 10 1961, when it announced it was building the C-5 rocket, which was later to metamorphose into the Saturn V. Saturn was conceived as a successor to the Jupiter series, hence the name.
Von Braun’s approach was a sound one. Unfortunately NASA was under a deadline, and if things continued as Von Braun wanted it, it would not make it by the end of the decade. Things changed fast when George Mueller assumed responsibility for the Apollo program as Director of the Office of Manned Space Flight in 1963. He immediately realized that NASA would not make the deadline, and started championing a different approach.
Instead of testing each part separately, he asked that the rocket should be assembled and the whole thing should be tested together. He too had extensive ballistic experience with ballistics at the army, and knew he favoured the “all up” approach. Von Braun was having none of it. He pointed out that if the rocket failed when it was fully assembled, they would not be able to pinpoint the failure. Ultimately it came down to rank, and Muller outranked Von Braun.
The Nov 9 1967 launch of the Saturn V was the culmination of Muller’s approach. This was the first time that NASA was testing many of the components and systems. If it failed, it would set back the program by several years, as the team would have to work out which component has failed. Fortunately for NASA, it big bet was successful. The launch went off without a hitch, and in December 1968 Apollo 8 took a crew to the moon and made history.