The space shuttle Discovery approaches the International Space Station in October 2007. Photograph: NASA/AP
On the morning of 12 April 1981, astronauts Robert Crippen and John Young took the lift to the top of the launch tower at complex 39A at Cape Canaveral in Florida and strapped themselves into their seats on the space shuttle Columbia. The pair were about to fly the world's first reusable rocket launcher, a 100-tonne chunk of revolutionary space technology. This was the first time Nasa had put men on an untested launcher and the nerves of its staff were by now severely strained.
For hours, engineers had been pumping hundreds of thousands of gallons of liquid hydrogen and oxygen into Columbia's fuel tanks. When combined, the two elements would generate more than a million pounds of thrust. A further kick would then be provided by two huge solid fuel boosters containing a highly explosive mixture of aluminium powder and perchlorate oxidiser.
The countdown reached its final moments, the point at which, according to former Nasa chief Daniel Goldin, "your breathing slows, your heartbeat becomes noticeable and an uncomfortable muscle tension fills your body". And he was just an observer.
Slowly, the minutes ticked away until, eight seconds before lift-off, the shuttle's turbo pumps – each powerful enough to empty a swimming pool in 20 seconds – started to force hydrogen and oxygen into the spacecraft's three main engines, where the two elements combined with unbridled ferocity. In seconds, temperatures in the engines soared to 6,000C.
Super-heated steam – generated by the explosive marriage of hydrogen and oxygen – erupted from the base of the spaceship; the computer ignited the two solid boosters; the giant bolts which had been holding the straining shuttle to the ground were blown open; and, at just after midday, Columbia rose gracefully into the air on a pillar of white vapour. Twenty years to the day that Yuri Gagarin had become the first human in space after orbiting Earth in a Vostok capsule, America had launched the first reusable spaceship.
For the next two days, Columbia circled the Earth. It was a bit like camping, as Robert Crippen later recalled. "We ended up sleeping in our seats and you had to pay attention to housekeeping, not to get things too dirty." Then, after 37 orbits, the mission's pilot trimmed Columbia's velocity, causing the spaceship to dip into Earth's atmosphere and on to a perfect, unpowered landing at Edwards Air Force base in California.
Columbia's flight was greeted with adulation. Its revolutionary engines had worked perfectly despite the colossal, violent heat of the combustion of its hydrogen and oxygen fuels, while its thermal insulation tiles had survived the searing temperatures of re-entry. The day of the expendable launcher was over. Space travel would soon be commonplace.
At least that is what Nasa said would happen. In reality, what occurred was a desperate disappointment. Flights of the shuttle – despite its brilliant engineering – never became commonplace. Columbia and its sister craft were supposed to make 50 flights a year, according to Nasa launch manifests. But only 132 shuttle missions were flown between 1981 and 2010, an average of 4.5 a year, a grimly inadequate figure for a craft that "will revolutionise transportation into near space by routinising it", as President Nixon announced in 1972.
Worse, two of the five shuttles that were built – Challenger and Columbia – were destroyed in accidents that killed 14 astronauts. In the wake of these tragedies, Nasa engineers became more and more safety-conscious and launch costs soared from Nasa's estimate of $7m a mission to almost $1bn. Thus the shuttle has become the costliest, most dangerous transport system ever built.
Now it is to be scrapped. At Cape Canaveral, engineers are now preparing to launch the shuttle Discovery, currently scheduled to blast off tomorrow on its final mission – to the International Space Station. There will be two more flights – Endeavour in February and Atlantis in June. Then the shuttle fleet will be grounded.
But how could this fall from grace have occurred? What turned the craft that soared so gracefully over Florida in April 1981 into a redundant, dangerous orbiting dinosaur? These are key questions, for until they are answered America (and the rest of the west which has relied so much on the ability to put men into space) will find itself floundering to find a role in space or a reason for being there. The US has got lost in space and the failure of the shuttle carries much of the blame. "The shuttle made America dependent on a fragile, expensive, risky launch system," says space policy expert professor John Logsdon of George Washington University. "It created the delusion of easy access to space. Now we are paying the price."
At the end of the 60s, the US triumphed over its Soviet space rivals because it spent vast sums on developing its huge Saturn V launcher which could hurl a manned craft to the moon with ease. After Apollo 11, Nasa asked that the Saturn V be allowed to ferry large modules into orbit, where a space station could be constructed by 1975. From there a Mars mission could be launched in the 1980s.
"President Nixon and his staff just looked at the plan and said, 'Are you kidding?'" says Logsdon, a white-haired, imposing but genial figure. "They were not interested in such a programme because they calculated it would do them no good in their term of office. They wanted a faster fix."
Instead, says Logsdon, Nixon and his aides simply took a map of the United States and looked at key states they needed to win to ensure victory in the 1972 presidential election. The decision came to set up a major aerospace programme involving these states. Construction of a reusable space shuttle, an idea that Nasa had also being toying with, fitted the bill. The agency was ordered to prepare detailed plans – on a very tight budget. The days of high spending on space were over and the Saturn V, which had put Americans on the moon, was dumped.
Stuck with limited resources, Nasa was in trouble, Logsdon says, and had to give up its original idea of launching the shuttle, piggyback-style, on a specially designed, manned jet plane. Both launcher and shuttle would have been reusable. Instead, to save cash the shuttle would be strapped to huge tanks that would provide fuel for its engines and to boosters that would provide extra thrust but which would be dumped during launch. The shuttle was not therefore a fully reusable spacecraft.
In addition, the agency wanted to use boosters that would burn liquid fuel, a relatively stable configuration, but in the end had to choose solid fuel boosters: an untested, less stable, but cheaper option. For similar reasons, a crew escape system was scrapped.
Then there was the involvement of the military. To find funds for the shuttle's development, Nasa asked defence chiefs to join in the project and use the spaceship to put all their military and surveillance satellites in orbit. The Pentagon agreed but insisted that the shuttle be capable of flying giant payloads on flights over the poles so that it could launch spy satellites to any part of the globe. This requirement meant the shuttle would have to re-enter the atmosphere on courses that needed far more robust, far heavier thermal insulation. Starved of cash by Nixon's White House, the agency was forced to agree.
"The shuttle was designed by a series of compromises to satisfy too many demands and too many requirements from too many different bodies," says Logsdon. "The result was a vehicle that could no longer achieve the basic goals that had been set for it."
Nevertheless, for the first four years of its operations, the shuttle – for all its flaws – operated well. It launched a total of 24 satellites, retrieved two broken communication satellites and repaired another in orbit. In addition, it not only flew US astronauts, it carried citizens of Germany, Mexico, Canada, Saudi Arabia and Holland into space.
But pressure was mounting on engineers who were finding it increasingly difficult to maintain the tight launch schedules imposed by Nasa as it tried to keep shuttle operations cost-effective.
On 28 January 1986, the spacecraft's deficiencies were exposed with deadly consequences. A seal in a booster of the shuttle Challenger failed at lift-off. Pressurised hot gas sprayed over the craft's fuel tank and the spaceship exploded 73 seconds into its flight. Binding together fuel tanks and boosters had had grim consequences.
The US – an intensely self-conscious nation – reacted with horror and grief. I covered the tragedy for the Observer and discovered Florida reeling in its wake. On the main road from the Cape to Miami, all the neon-lit signs on the strip had been changed from offers of cheap meals and lodging to messages: "May God protect the shuttle crew"; "We pray for the Challenger astronauts". The normally busy bars of Cocoa Beach, near the Cape, were empty. Locals spent the days following the explosion on the beach, hunting in the sand for any scrap of debris to hand over, desperate to feel that they were, in some way, helping
At the time, Nasa insisted the crew had been killed instantly. But the debris revealed a different story: several astronauts had survived Challenger's initial break-up but, without an escape system, had perished when their crew compartment crashed into the ocean. It was also discovered that Nasa managers had disregarded warnings from engineers about the dangers of launching after the Cape had experienced near freezing temperatures the night before lift off. The cold caused the breaking of the booster seal and doomed the flight.
After Challenger, the launch of commercial satellites from the shuttle was halted; a number of major changes were made to Nasa operations; and a replacement craft, Endeavour, was ordered. For its part, the Pentagon simply abandoned the shuttle; it closed down its special $3bn launch facility in California – without a single craft having lifted off from it – to leave the spaceship lumbered with the cumbersome thermal tiles that defence chiefs had insisted must be fitted. "It's tragic. It made the shuttle far heavier than necessary – but then there are so many tragic stories when it comes to the shuttle," says Logsdon. In the end, it is estimated that the accident cost the US a total of $12bn.
In September 1988, shuttle launches resumed with the lift-off of Atlantis. Again, Nasa insisted it was dealing with a fully operational, properly tested vehicle – and not an experimental craft, as it really was – and so set up a stiff schedule of flights that later included plans to ferry components to the International Space Station (construction of which began in 1998).
And again the agency ignored the warnings. In 1989, the US Office of Technology Assessment calculated there was a 50-50 chance of losing another shuttle "within 34 flights", while the Augustine committee, charged with investigating the future of the US space programme, warned Nasa was "likely to lose another space shuttle in the next several years".
The agency took no action. This was a problem, says Scott Pace, head of the Space Policy Institute in Washington, that could be traced to a simple flaw. "Nasa was trying to do too much with too little for too long a period because there was not a fundamental policy and political rationale for what it was doing." In other words it was pottering about in low Earth orbit with little purpose.
On 1 February 2003, the inevitable happened: Columbia disintegrated over Texas after it had re-entered the atmosphere and was preparing to land at the Kennedy Space Centre at Cape Canaveral. This time the cause was traced to a briefcase-sized piece of foam insulation that had fallen from the shuttle's external tank during launch. The debris had struck Columbia's left wing and damaged its thermal protection. As the craft swept into the atmosphere, hot gases generated by its passage through the atmosphere poured into the ship and eventually broke it apart.
"After the Columbia accident, a lot of us had a reality check," says Pace, talking in his Washington office. "Yes, the shuttle was a magnificent vehicle but surely it was done for now, we thought. The American part of the space station had already been built by then but not the European or Japanese components. So we asked our international partners if they still wanted to proceed.
"To our surprise, they said yes, we should see it through if we could. It was worth the risk. If they hadn't, that would have been the end of the shuttle there and then."
So far, those last two dozen missions, which have left the space station nearly completed, have gone well, with only three more to go. What follows is more difficult to assess.
After the shuttle's final flight in June 2011, the US will have to rely on Russian spacecraft to ferry astronauts to the space station, an ignominious position for the winner of the space race. At the same time, America's plans for a replacement launcher are shrouded in uncertainty. President Obama cancelled the Constellation programme that would have returned America to the use of expendable launch vehicles. Instead, private launch companies, with US government support, will fly missions to the space station, the president said. At the same time, Nasa will pursue a new, undefined heavy launch system.
It is all very vague and unsatisfactory. Yet many senior space officials refuse to put the whole blame for this confusion on the shuttle. "It was not an unqualified success but equally it was not a complete disaster," says Roger Launius, Nasa's chief historian. "The real tragedy is that we stuck with the shuttle for 30 years."
This is key. The shuttle was a test craft that demonstrated most but not all of the technology needed to create fully reusable spacecraft. However, under White House pressure, Nasa treated it as a fully operational craft.
"The shuttle should have been given an honourable retirement, which it certainly deserves, in the 1990s, and from the lessons learned a second-generation, fully reusable launcher would have been constructed," says Launius. Professor Logsdon agrees: "The shuttle was a first generation experiment in reusability and affordability. Not replacing it in the late 80s or early 90s was a failure of national leadership."
Viewed from this perspective, Discovery's lift-off tomorrow should be seen not as a triumph of high technology, but as the launch of an old space bus that long ago served its purpose and which should have been replaced by a craft that properly befits a nation with true aspirations in space. "The trouble is that America doesn't know why it is in space any more," adds Pace. "That is the real problem."
One thing is certain. Nerves at Kennedy Space Centre will be as taut as they were for that first shuttle launch day in 1981. "Most senior people at Nasa will be very happy to get this mission and the next two flown safely and then send the vehicles gracefully into museums," says Logsdon.
Exactly which museum will get a shuttle has yet to be decided, though each will make a perfect monument: to engineering ingenuity – and botched political decision-making.
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