Designing for Spacflight the story so far.
As the race to 'conquer' space began to heat up, the Soviets remained one step ahead of the Americans.... for a while. The Soviets put a dog into orbit before an American monkey rode a suborbital rocket--but, as Colin Ledsome CEng FIED wryly points out in part 2 of his space exploration, at least the monkey came back!
THE APOLLO ERA
US president John F. Kennedy, pictured below, could not have announced the intention to reach the Moon without reassurance from the advocates of space exploration, particularly Werner Von Braun. However, the practical evidence for the feasibility of such a mission came from existing successful work on missiles and the existence of a vast manufacturing infrastructure built up during World War II.
The V2 tests at White Sands had led to a series of missile programs such as Redstone, Minuteman, Thor and the submarine-launched Polaris. A range of missiles for air-to-air, ground-to-air, ship-to-ship and all the other combinations of operator-to-target combinations, right up to intercontinental ballistic missiles, were in service or planned before Kennedy spoke.
Early proposals had taken a more cautious approach of establishing a space station first, then assembling a Lunar vehicle in orbit. The Kennedy announcement went straight for a ground-launched Lunar mission, a much more adventurous approach.
The preliminary work had been brought together by a new civilian organisation, the National Aeronautics and Space Administration, NASA. It was formed in October 1958, absorbing the earlier National Advisory Committee for Aeronautics with several research laboratories and 8 000 staff. A new facility, the Marshall Space Flight Center, was carved out of the Redstone Arsenal, Huntsville, with Von Braun and his team leading activities. Missile projects such as Atlas, Titan and Saturn were transferred from military to civilian use. The public face, in the West, was civilian and scientific, in order to avoid exacerbating the danger of further heating up the cold war.
ONE STEP AHEAD ... ONE BACK
For a while, the Soviets remained one step ahead of the Americans. They put a dog into orbit before an American monkey rode a suborbital rocket, but at least the monkey came back! On 12 April 1961, Yuri Gagarin--pictured above, right--became the first human to orbit the Earth in Vostok 1. The Americans replied on 5 May by launching Alan Shepard on a sub-orbital flight in a Mercury capsule. Then, on 25 May, in response to growing public concern, Kennedy then announced an intention to land a man on the Moon and return him safely to Earth within the decade, initiating the Apollo program. On 7 August, the Soviets put German Titov into orbit in Vostok 2. It wasn't until 20 February 1962 that the USA launched John Glen into a three-orbit mission in Friendship 7. (The '7' referred to the initial seven test pilots selected to become astronauts.)
By June 1962, the Soviets had launched six cosmonauts in Vostok capsules, amassing a total of 260 cosmonaut orbits and 16 days in space. By May 1963, the USA had only launched six astronauts in Mercury capsules, logging 34 orbits and a mere 51 hours in space. On 16 June 1963, the Russians launched the first woman in space, Valentina Tereshkova (she forgot her toothbrush!), in Vostok 6. The first American woman in space, Sally Ride, did not fly until 20 years and two days later on a Shuttle mission.
LONGER RANGE QUEST
Alongside all this, the UK had developed and tested its own atomic (fission) weapons and later hydrogen (fusion) bombs. As in America, there was a need for a delivery system. Bombers were seen as increasingly vulnerable to interception by defending aircraft or missiles. The RAF was equipped with Thor medium range missiles, but something with a longer range was needed. Development began on the Blue Streak missile, based on the American Atlas, but with all-British design and manufacture, using Rolls-Royce engines. (These were based on an American design, but were lighter, producing 10% more thrust.) Static test stands were constructed at RAF Spadeadam in Cumbria, along with excavations for a prototype underground silo built to withstand a nearby nuclear blast. Silos were planned at some 60 sites in eastern Britain, but none was ever built. The design for these silos was --exported to America where it was used extensively. From Spadeadam, Blue Streak would have been able to reach Moscow. Since no site in the UK was suitable for flight tests, a launch site was developed at Woomera, Australia.
The missile was intended to replace the V-bomber fleet as it came to the end of its projected service life in the mid-60s, but escalating costs and reducing political support led to its cancellation in 1960 after a number had been built. The American Skybolt missile was to be the replacement delivery system. The military version of Concorde, and its partner programme TSR2, were designed to carry it. (All civilian Concorde aircraft had unused mounting points for Skybolt built into their wings.) Then the Americans cancelled Skybolt.
Several proposals were put together to mate a Blue Streak first stage with a Black Knight rocket, or adding the larger Black Arrow as a second stage, to make an all-British range of launchers able to reach as far as geostationary orbit. (Military projects were usually titled 'Blue something' and civilian projects 'Black something'.) A number of other combinations were considered. The UK was arguably number three in the world.
After negotiations in the early 60s, the European Launcher Development Organization, ELDO, was set up to place a French second stage and German third stage on a Blue Streak as a civilian satellite launcher, Europa. Ten launches were made from Woomera, with Blue Streak working well, but problems with the upper stages plagued the project. Woomera could only launch to the north and could not put satellites in a geostationary orbit, so the project was moved to a new launch site at Kourou in French Guiana, but again had problems and the UK pulled out in 1968. Kourou became the launch site for the later series of Ariane vehicles.
SUCCESSFUL UK INDUSTRY
The UK opted out of major involvement in launcher development for the next forty years, buying American missiles and warheads and paying more than any other country for access to research, communications and survey data from other national programmes. (From the mid-60s to the end of the century, the UK government spent less on its own national space programme than Portugal!) In 1968, the British Aircraft Corporation proposed 'MUSTARD', Multi-Unit Space Transport And Recovery Device, a modular system capable of being assembled in various configurations to put a range of payloads Into orbit. It received no political backing in the UK, but may have influenced the later design of the Shuttle. Even so, a successful UK industry has grown up via a variety of contracts supplying components and instrumentation internationally and building small satellites for many customers.
Meanwhile the Apollo program was gathering pace In the USA, with growing achievements and occasional disasters. Politically, the competition with the Soviets was enough to guarantee the high levels of funding needed. Indeed, it can be argued that the American success in gradually overtaking the Soviets was due to their ability to outspend their cold war rivals. In fact, the Soviet modular approach, of assembling major components produced in large numbers to make whatever size vehicle they needed, was far cheaper than the US way of designing each family of vehicles from scratch. (It is still possible to use the engines that were used to launch Sputnik 1. If you want more thrust, you add more engines. The Americans start again and design bigger engines.)
The timescale laid down by president Kennedy, of reaching the moon within the decade, became the ruling factor for many decisions. The Saturn SI, the first stage of the Saturn I launcher, had been made by clustering together the tanks of several existing Redstone and Jupiter vehicles. This was later upgraded to the S1B, with new tank structures, used for Saturn V. Forward planning put infrastructure in place to cover projected future developments. At Cape Kennedy, facility to produce liquid hydrogen, LH2, was built. This was bigger than all previous LH2 facilities in North America put together. The Vertical Assembly Building, VAB (see box), one of the largest buildings in the world, was designed and built in time for the first Saturn flights. The old wartime tank factory at Michoud, near New Orleans, was taken out of mothballs, had a turntable built to turn 30 ft diameter (9.14 m) rings for the SIB and began to produce a different type of tank. It went on to make the external tanks for the SLS (Shuttle) and is still busy today.
The Saturn V assembly had a take-off mass of 6,698,700 lb (3,038,500 Kg) and a first stage thrust of 7,584,582 lbf (33,737.90 kN). The maximum payload put into orbit was 260,000 lb (118,000 kg). Some 90% of the lift-off mass was liquid fuel and oxidant. Coupled with the Apollo modules, it remains the most complex machine ever built.
TO THE MOON AND BACK
The story of Apollo is well known and briefly summarised here:
Apollo 1--On 27 January 1967, a preflight test came to a tragic end when a fire broke out in the oxygen atmosphere of the Command Module. CM. Virgil Grissom, Edward White and Roger Chaffee lost their lives. The project was put on hold and a safer atmospheric mix was introduced. It was re-designated Apollo 1 as a memorial.
Apollo 7--This was the first manned flight on 11 October 1968, after several unmanned tests. Launched on a Saturn I, two-stage vehicle, Walter Schirra, Walter Cunningham and Donn Eisele orbited for more than 10 days (longer than a Lunar mission) and tested all of the Command and Service Module (CSM) systems. Despite a few minor problems, the flight was a success. For the first time, an onboard TV camera broadcast directly to the public channels.
Apollo 8--On 21 December 1968, a Saturn V launched the first manned mission to orbit the moon in the Apollo CSM. Frank Borman, William Anders and James Lovell saw the far side of the moon out of contact with Earth, as they did ten orbits before returning to Earth. They did six telecasts, including a famous Christmas Eve broadcast wishing a Merry Christmas to all.
Apollo 9--This was the first flight to include the Lunar Module, LM, launched on 3 March 1969. During 151 Earth orbits, James McDivitt, Russell Schweickart and David Scott undocked, manoeuvred and re-docked the various parts to test all the systems needed for a Lunar Landing.
Apollo 10--Thomas Stafford, Eugene Cernan and John Young took the complete Apollo assembly back to the moon to test all systems and components, but not actually land! They launched on 18 May 1969 and the CSM and LM followed separate orbits, overflying the future landing sites and carrying out engine starts and manoeuvres with both the lander and ascent stages of the LM.
Apollo 11--This was the big one. On 16 July 1969, Neil Armstrong, Edwin Aldrin and Michael Collins launched to achieve the Kennedy goal of landing on the Moon and returning safely to Earth. Armstrong and Aldrin landed the Eagle LM on 20 July in the Tranquillity, with some 300 million people watching on television. They were on the surface for just 21% hours, with both spending only 2% hours outside the LM. They returned to Collins in the orbiting Columbia CSM and fired its engine behind the Moon to land in the Pacific Ocean on 24 July 1969.
Apollo 12--On 14 November 1969, Charles Conrad, Alan Bean and Richard Gordon were only 36 minutes and 52 seconds into their flight when their vehicle was struck by lightning. (The Kennedy meteorologist was fired.) After extra checks in orbit, the flight continued and the mission was very successful. An experimental package, including a seismometer, was left on the surface and parts of Surveyor III, a probe which soft landed nearby on 20 April 1967, were recovered. After transferring to the CSM, the Lunar Ascent Module was crashed into the surface to test the seismic characteristics of the Moon. "It rang like a bell", showing that the Moon was solid right through. Television broadcasts were again made, but the audience interest was fading.
Apollo 13--On 11 April 1970, the launch was not shown live on American television; Apollo had become routine. Then, on route to the Moon, an Oxygen tank in the CSM failed and the world sat on the edge of its seat as James Lovell, Fred Haise and John Swigert nursed their stricken craft around the Moon and back to Earth. You've seen the film, so you know how it ends.
Apollo 14-17--The next four flights carried out a number of experiments and drove a Lunar Rover across the surface. Several retro-reflectors were left in place and a high-power laser, coupled with a large telescope, can be seen reflected back from these points on the Moon.
Later lunar missions were cancelled, since, politically, the space race had been won and further flights were seen as an unnecessary expense. A joint mission with the USSR saw an Apollo-Soyuz link up to test joint systems for a future space station. The major project was Skylab, the first true manned space station. The only survivor of a program to make extensive use of the Saturn and Apollo technology, Skylab was almost a disaster when its meteoroid shield broke away during launch. It was used by three crews to carry out a number of experiments and act as a solar observatory with eight telescopes. (This was before high definition digital cameras and the crews had to carry out space walks to change the film!)
An analysis of the Apollo program outcomes showed that it had developed new materials, computers, project management systems, manufacturing capabilities and much more, which had benefited the economy of the USA by ten times the cost of the program.
All this came too late. Further work on Apollo was cancelled, followed by a long pause while the Space Transportation System was being developed ... otherwise known as the Shuttle.
The Vertical Assemble Building
The Vertical Assembly Building was built to allow up to four vehicles to be assembled at the same time. It is 550 feet (168 m) high, with doors opening to give a 500 foot (152 m) clearance. Saturn V was only 334 feet (102 m) high and was mounted on a crawler, which added another 50 feet (15 m). The VAB was designed to take Nova, a much larger vehicle, which never left the drawing board. It is the second largest building in the world by volume (only the Boeing factory in Seattle is larger).
It has a large air-conditioning system to avoid internal cloud formation in the humid air of Florida. Each quadrant has remotely controlled cranes in the roof, capable of delicately positioning rocket stages to high accuracy. (Coping with the considerable lengths of crane lifting cables, and small movements necessary, was a significant design challenge with 1960s technology.)
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|Title Annotation:||THE SPACE RACE|
|Date:||Sep 1, 2016|
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