What it was: A European effort to turn their contribution to the American space station Freedom into an independent space station of their own, hoisted into orbit by ESA rockets and serviced by an ESA shuttle.
Details: The European Space Agency signed on to Ronald Reagan’s suggested internationalization of the Freedom station right from the moment he made the offer in 1984. They had been developing the pressurized Spacelab module for use in the Space Shuttle’s cargo bay since the early 1970s, and now pushed for the new space station to build on components derived from their work. As part of this they started the Columbus project, which among other goals would have them make one such component—the Attached Pressurized Module (APM)—on their own for inclusion in the completed Freedom.
Another part of the project was to be semi-autonomous right from the initial planning, though. The Man-Tended Free Flying Platform (MTFF) was to have been a two-segment unmanned Spacelab module which would detach from Freedom and move to a nearby orbit. This would allow for sensitive, teleoperated microgravity experiments away from the noisy, manned Freedom and, a round of experiments completed, it would return for maintenance at the main station.
During the mid- to late-1980s, though, Freedom had a rough ride in the US Congress and the ESA started developing contingency plans for what to do with Columbus if the American station was cancelled. Couple this with massive increases in prices to use the Space Shuttle—then the Challenger disaster temporarily making its cargo bay unavailable at any price—and from 1989-92 these plans culminated in an entirely autonomous station that the Europeans would try if remaining part of the now downsized and re-named Alpha (AKA “Space Station Fred”) became too unpalatable.
The initial station would have been the unmanned MTFF, but now the experiments would have been retrieved by the ESA’s Hermes shuttle, which along with the Ariane-5 rocket had been approved as an unrelated project in 1987. In 1991 the three were melded into one big project.
The MTFF, Hermes, and the French launcher were to be joined by a fourth piece of the puzzle: the APM, now divorced from Alpha. Once the unmanned MTFF-based station was proven, the APM would be completed and launched on an Ariane-5 (or possibly in an US Shuttle’s cargo bay, if renting it turned out to be cheaper and more convenient). It would then dock with the MTFF to produce an entirely European manned facility, Columbus. The long-term, if somewhat nebulous, plan was then to add more and more modules as time went by.
Statistics on the Columbus are surprisingly hard to come by. Based on the actual ISS module that was derived from it, though, we can presume that its two working modules would totaled about 14 meters in length, with the power module and station-keeping ion engine at the MTFF end adding about another 5 meters. Its total mass would have been in the range of 25 to 30 tonnes, which would have made it a bit bigger than the Soviet Salyut stations, but less than 25% the size of Mir and about 6% the size the ISS. Accordingly it probably would have had the same sort of missions as the Salyuts, involving two or three astronauts for a few days up to several months.
The budget for the station was calculated at US$5.3 billion, including operations for five years.
What happened to make it fail: Two trends pulled the APM back to where it started: attached to the ISS.
First, the United States got its act together. The Space Station passed through another session budget shrinkage and soul-searching under Bill Clinton in 1993, but finally stabilized into what is recognizably the ISS that got built. As uncertainty over the American contribution faded away, and the Russians signed on to ISS rather than build Mir-2, it became clear that it would be safe to co-operate rather than go it alone—though the ESA did keep contingency plans for Columbus in place as late as 2001.
The ESA itself was also running into budget difficulties. The collapse of the Soviet Union did open up another possibility, as there was talk for a while of perhaps attaching the APM to Mir-2, but a related event back down on Earth proved to be more important. The costs of German reunification made Germany scale back its contributions to the ESA by nearly a fifth, which brought a budget crunch to the agency as a whole. With Hermes already over-budget, it was cancelled entirely, as was the MTFF, and the APM’s costs were scaled down by committing to the American station project after all—the name Columbus was co-opted for it alone rather than the entire project, and it became the Columbus science laboratory module that was attached to the ISS in February 2008. Only the Ariane-5 launcher managed to emerge from the crisis unscathed. As it turned out, the late 80s and early 90s were something of a Golden Age for European manned space exploration. Not only has the over all ESA budget been declining slowly since then, the percentage of it devoted to manned space travel has dropped precipitously. The ESA’s focus has shifted to more commercial uses of space such as telecommunications satellites and the Galileo satnav system.
What was necessary for it to succeed: The main necessity is the stillbirth of the ISS, which isn’t too hard to engineer. The Challenger disaster had called it into question, repeated budget cuts hit it in 1989 and 1990, and in June 1993 a bill to cancel its immediate ancestor Alpha had failed by only one vote in the House of Representatives.
Given that event, the budgets floated for MTFF even after the Germans had run into reunification money problems had it flying by 1999 so long as the ESA doesn’t make the real world turn into budgeting more for commercial applications that it did. This gives us the first component of the station.
If MTFF did get off the ground, the next component of the program was still very likely to have changed. Hermes was not going to fly on a reasonable budget in a reasonable timeframe, which kicks out one leg of the station’s autonomy. However if the MTFF had gone ahead it’s likely that the ESA could service it with an (relatively) quick upgrade to the simpler Automated Transfer Vehicle they had begun developing in the mid-1990s. It flies in the real world on unmanned missions to the ISS, and its manufacturer EADS Astrium has been floating a proposal to turn it into a manned capsule since 2008. British Aerospace had actually suggested manning and supplying the station using a capsule of their own design in the mid-80s, only to have it squelched in favour of the French mini-shuttle.
The combination of an MTFF serviced by a manned ATV would likely have worked, leading to the attachment of the APM and a completed, manned ESA station Columbus sometime in the middle to late 2000s.