Early construction

WHAT IS THE INTERNATIONAL SPACE STATION?

Today, the National Aeronautics and Space Administration (NASA) is proud to boast that the American-led International Space Station (ISS) is the result of years of co-operation between 16 countries. It was not always so, the American-led effort to build a space station with its political allies in Europe and Japan began as an attempt to construct a station that would be better than the Soviet-launched Mir space station. President Reagan called that effort Space Station Freedom, claiming that political freedom was something that America, Europe, and Japan shared while the Soviet Union suffered under a Communist dictatorship. Space Station Freedom represented the dying throw of America’s effort in the Cold War-driven Space Race that had begun with Sputnik and ended with Mir. Whilst America had stunned the world by landing six Apollo flights on the Moon, that effort was not sustained. The Space Shuttle was an iconic flying machine, but until Space Station Freedom was authorised it had attempted to be all things to all people and its design had suffered as a result.

The Space Station Freedom effort was driven by the desire to prove American technological superiority over the Soviet Union. With the long-duration Mir (a modular space station that was built up gradually with extra modules being added to it in orbit and permanent occupation being supported by a regular supply of fresh Soyuz spacecraft and Progress cargo vehicles) as the benchmark, America strove to design a station that would hold a six-person crew (twice as many as Mir’s three cosmonauts) and produce top-quality science. To that end, America, Europe, and Japan would each construct a scientific laboratory to be added to the station. Over the years the Space Station Freedom design grew beyond what was realistically sustainable, with pressurised modules docked to a huge girder-like structure and even a large repair shop where malfunctioning satellites would be recovered and repaired on-orbit, before being released to continue their missions. Individual

elements of the station would be delivered by the Shuttle. Science would be auto­mated when no Shuttle was present, but tended experiments would be performed by visiting Shuttle crews. The station would not be permanently occupied until the six – person Habitation Module, the last element, was installed and a six-person American Crew Return Vehicle had been developed to allow the crew to evacuate the station in the event of an emergency when no Shuttle was present.

Billions of dollars were spent on the design process before any metal was cut to begin construction of the station’s modules. Budget restraints finally bit hard, and Space Station Freedom was continually redesigned in an attempt to bring spending under control. One such redesign saw the size of the pressurised modules halved in length to save money. In another, the satellite repair shop was discarded. The huge, square truss was replaced by a much smaller version. European plans for an Ariane-V launched free-flying laboratory, called Columbus, that could be docked to Space Station Freedom when required, and serviced by a European mini-Shuttle called Hermes were shelved due to budget restrictions. A smaller Columbus would be launched on the American Shuttle in return for services rendered, and would remain permanently attached to the station. Hermes would not be built. Likewise, the Japanese plans to develop the H-II Orbital Plane Experimental (HOPE) mini-Shuttle came to nothing.

Space Station Freedom was redesigned almost yearly in an attempt to bring the spending under control, while all the time eating further into its initially allocated budget. On one occasion, a Congressional vote to continue building the space station, rather than scrap it completely, was passed by a single vote. Meanwhile, Mir taunted the Americans from on high, as the station that was designed to operate for just 5 years was permanently occupied for the majority of its 15-year operational life.

When Soviet Communism collapsed in Eastern Europe it was America’s President Clinton who insisted that the Russians be invited to join the space station effort, in order to prevent their missile experts selling their knowledge to states that were unfriendly towards America. With the Russians now included in the team, the station’s name changed to the International Space Station, a name that had been used in some quarters from the time when the Europeans and Japanese had first joined the effort.

In the meantime, American astronauts began training in Russia before perform­ing long-duration flights on Mir with Russian cosmonauts. The first NASA astronaut was delivered to Mir on a Soyuz and recovered by the Shuttle. The remaining Americans were delivered to Mir and returned to Earth on the Shuttle. The experi­ence of the American astronauts on Mir was not a happy one, with several suffering symptoms of isolation and depression. Many of their post-flight writings show a typical Cold War American attitude towards their old enemies. Nothing the Russians possessed or did was good enough for certain members of the American Shuttle-Mir team! Two outstanding exceptions to this were British-born Michael Foale and female astronaut Shannon Lucid.

A new design was established for ISS, with a number of Russian modules in the critical line. A TKS-style module would provide attitude control and electrical power during the earliest phase of the construction. A second module, similar to the Mir base block, would provide early sleeping quarters and an operations centre. Employing the Soyuz/Progress routine, proven on the late Salyut stations and Mir, would allow permanent occupation and science to be undertaken from the earliest stages of construction, rather than only towards the end, as envisaged for Freedom. A Docking Module/airlock would provide support for the Russian Orlan-M EVA suit.

Alongside the Russian modules the Americans would install Node-1, a berthing station for later modules, and an electrical attitude control system, consisting of four gyrodynes in the Z-1 truss, mounted on the zenith of Node-1. The Port-6 (P-6) truss element, a single piece of the Integrated Truss Structure (ITS), would be temporarily mounted on the Z-1 truss and its Solar Array Wings (SAWs) deployed to provide additional electrical power while the American sector of the station was built up. A temporary ammonia cooling system was also established using the radiator on the P-6 ITS. The American science laboratory would become the centre of the American sector of the station, taking over many of the control operations previously per­formed by the Russian modules, and the American Joint Airlock would provide support for both the Russian Orlan-M EVA suits and the American Extravehicular Mobility Unit (EMU). The massive pieces of the ITS would then be delivered and constructed in orbit, with their SAWs and cooling radiators being deployed as the individual ITS elements were added to the station. As the ITS progressed, the station’s electrical and cooling system would be reconfigured into its permanent configuration. The P-6 ITS would be relocated to its final position, as the final element on the port side of the ITS. Then Node-2 would be delivered to serve as the mounting for the European and Japanese science laboratories, which have still to be delivered to the station as this manuscript ends. Finally, Node-3 would bring additional sleeping quarters, allowing the station’s crew to finally be raised to six people.

October 4, 2007 was the 50th anniversary of the launch of Sputnik, the first artificial satellite. It has required every second of those 50 years of experience to allow the development, construction, and occupation of ISS to take place. In those 50 years both America and Russia have developed their own engineering methods and infra­structure that has made their spaceflight programmes possible on the grand scale that they have followed. As a result, two extremely proud cultures clashed when America invited Russia to join the ISS programme. The Russians felt that they had begun the Space Age and had achieved many of the major “firsts” in the early years. Having lost the race to the Moon they had concentrated on developing space stations and the infrastructure required to support them. They initially feared that the Americans were intending to strip them of their knowledge relating to long-duration spaceflight and then discard them. All training of American personnel in Russia took place in the Russian language, requiring the Americans to learn that language before they could advance to detailed spaceflight training. All training manuals were produced in the Russian language, with no English translations. Despite repeated requests from their new colleagues, the Russians refused to produce English translations of vital docu­ments unless the Americans paid heavily inflated prices for them, in US dollars. Trust between the old enemies came very slowly, usually only after personal friendships had been developed between individuals performing the same role on both teams. Facil­ities in Russia were often decrepit when compared with similar facilities in America. In many cases, Russian training facilities were of a lower fidelity than their American equivalents. Even the living quarters were of such poor quality, when compared with homes in America, that NASA shipped in a number of houses in kit form for their personnel to live in. The houses were assembled by a Russian workforce. In the basement of his new home, future Expedition-1 Commander William Shepherd established “Shep’s Bar” and gymnasium, which became a focal point where American astronauts and Russian cosmonauts could relax in each other’s company after the working day finished. Shep’s Bar and gymnasium remained in place and continued to function many years after Shepherd had completed his occupation of ISS. Several American astronauts have mentioned Shep’s Bar in their memoirs and have credited it with being one of the most important elements responsible for breaking down the barriers that originally stood between the Americans and Russians.

When the first female American astronauts began training in Russia they were disrespected by their hosts, many Russians joked that Shannon Lucid was flying to Mir, because it was dirty and required cleaning. The Russians had even stated publicly that when Russian women return to space it will be “in the strong arms of their male colleagues.’’ It was an attitude that did not go down well with the American women. Over the years the Russian attitude has changed, as the American women, many of them military officers or doctors of various scientific disciplines, proved beyond all doubt that they had the educational standards, technical know­how, and physical capabilities required to meet all of the demands of the Shuttle-Mir and ISS programmes. Today a professional respect exists to the point that, while one female Russian cosmonaut has been removed from two Soyuz crews in order to fly commercial spaceflight participants (SFPs), male Russian cosmonauts have served under American female Shuttle commanders and the first female ISS commander.

Regretfully, given the dire state of the budget for the Russian space programme, this proud organisation now finds itself reduced to little more than the role of delivery driver, with its Soyuz spacecraft delivering crews to ISS and returning them to Earth, and their Progress vehicles regularly re-supplying consumables on the station. Even then, the transfer to a capitalist economy in Russia and the reluctance of the Russian government to fund the space programme has led to regular disruptions in the large Space Station module, Soyuz, and Progress production lines as contractors withhold vital spacecraft equipment until they are paid for in full. Time and again, NASA has been required to provide additional money to Moscow in order to help the Russians meet their commitment to ISS. This has been necessary primarily because all of the Russian modules were in the critical line of ISS development and occupation. Without the first Russian module there was no early electrical power, no attitude control, and nothing to add the American modules to. Without the second large module there was no onboard oxygen production system, crew living quarters, or orbital re-boost capability. Without Soyuz, the crew had no emergency escape system and therefore could not permanently occupy the station. Progress was vital in re­supplying the propellant, oxygen, and water supplies in the Russian modules as well as providing fresh food, dry goods, and vital personal items and letters from the crews’ families. In short, without the Russians there was no ISS in its present form.

America trailed behind the Russians in the early years of the space programme, only overtaking early Soviet achievements in late 1965. Project Apollo landed 12 men on the Moon and then led to the Skylab prototype space station. Skylab was a mixed blessing. It gave America its first experience of long-duration spaceflight, and the endless onboard maintenance required to occupy a space station. It also led to the first strike by astronauts in space, when the Skylab-4 crew rebelled against the workload placed upon them in the early part of their flight.

The Shuttle was designed to be America’s only launch vehicle, planned to replace all one-shot launch vehicles, as demanded by President Richard Nixon. Its final shape and size were dictated by the large reconnaissance satellites that it had to be capable of launching. As a result, the Russian Salyut stations and Mir’s individual modules would fit in the Shuttle’s payload bay with room to spare. From the beginning, NASA wanted the Shuttle to be used to launch the elements of an American space station, but for many years no funding was forthcoming for that station.

The overall success of America’s space programme meant that NASA’s name has come to represent excellence in western culture. This attitude only began to fade as several Shuttle-launched satellites failed to achieve the correct orbit and the Hubble Space Telescope was launched with ineffective optics. A number of rescue and repair flights went partway to recover NASA’s reputation and the loss of several probes to Mars owing to efforts to fly “cheap” missions has been balanced by the more recent success of several robotic rovers used to explore the Martian surface. As a result, it was a confident, if not over-confident, organisation that clashed with Russian pride when budget restrictions dictated that the two superpowers pool their spaceflight experience.

The clash of cultures was perhaps felt most by the American astronauts, many of whom, on being removed from their families and relocated to Russia felt isolated. American astronauts are pilots, engineers, and scientists. They are encouraged to get involved in the development of the spacecraft they will fly and the experiments they will perform. Their input is often responsible for the redesign of equipment or procedures. In training they work closely with NASA’s Flight Operations Director­ate, which writes their Flight Plan, runs their training regime, and operates Mission Control. In the event of a malfunction or other problem in flight, the astronauts’ input is as important as that of the engineers on the ground. In Russia they found that the cosmonauts had no input into the design of their vehicles, flying whatever hard­ware was delivered to the launch pad by the contractor. In Russia, mission control dictates what happens on a spaceflight, to the point that Americans working in Russia during the Shuttle-Mir programme found that Russian cosmonauts were not offended by a poster that showed mission control operating the Mir space station, which hung from a set of puppet’s strings. The Americans, astronauts and controllers alike, found that the poster offended their professional respect for each other. While American astronauts received a standard Civil Service salary, based on their military rank, or civilian Civil Service grade, irrespective of whether or not they were in flight, Russian cosmonauts received a basic wage, much less than the Americans, and a basic sum when they were launched into space. They were then able to earn bonus payments if they completed individual in-flight goals, such as EVAs, or a manual docking of the Soyuz spacecraft in the event of the automated system failing. It was also obvious to the Americans that, if anything went wrong on a Russian spaceflight, the blame was usually laid at the feet of the cosmonauts, rather than in mission control, or at the door of the contractor who built the item concerned.

Another major difference that was obvious to the American astronauts was Russia’s reliance on automated systems in their spacecraft. With the exception of the Soyuz spacecraft, all Russian ISS modules were launched into orbit and thereafter used their own guidance and attitude control to complete their automated flight regime. Even the primary systems on the Soyuz were automated, with the manual override intended for use only if the automation failed. In America, the astronaut was part of the control loop in the first several generations of spacecraft. All major in­flight manoeuvres, including rendezvous and docking, were performed manually. The Apollo lunar landings were performed with a pilot at the controls, as were all Shuttle landings, although the latter make maximum use of standard airport automated landing systems. No American spacecraft after Mercury would have been capable of performing its mission without the onboard computer(s), but even then computer software was more often than not changed and even updated in flight by the human crew. The Russian preference for automation was equalled on ISS by America’s preference for robotics and human input. Where the Russians would have docked the major ISS elements together using automated systems, the Americans preferred to launch inert ISS modular elements on the Shuttle and then use the Canadian built RMS, operated from within the Shuttle’s aft flight deck, or the SSRMS, operated from inside the American Laboratory Module, and human astronauts operating outside the station on EVAs to attach the new elements to the station.

While the individuals in Russia and America’s space programmes may have learnt how to work together, pooling their individual talents and national expertise, there will always be political manoeuvring behind the scenes, and politicians in both countries, eager to drive their own agendas, who will blame the other country for all of the ISS programme’s ills. No doubt the accusations will continue in both directions as long as Russia and America continue to co-operate on space exploration.

Creating the International Space Station, the first book in this series, described the convoluted history of ISS, along with the Shuttle-Mir programme (ISS Phase I), and the on-orbit construction of ISS Phase II and ISS Phase III in detail and in the correct chronological order. The account that follows is a very brief description of the flights covered in that volume. While these descriptions are in the correct chronological order, they contain very little detail. Even so, the account should remind the reader how the early ISS modules were delivered into orbit and joined together.

The first Russian ISS module, Zarya, was launched into orbit by a Proton launch vehicle, on November 20, 1998. It was followed by an American Shuttle, STS-88, launched in December 1998. STS-88 carried “Unity”, the first of three nodes, with a Pressurised Mating Adapter (PMA) on either end. The Shuttle’s RMS was used to manoeuvre Unity from its mounting in the payload bay and dock it (via PMA-2) to the Shuttle’s own docking system. The RMS was then used to take hold of Zarya and dock it, via PMA-1, to the free end of Unity. Following several days of operations inside the station, Unity was undocked from the Shuttle and the Zarya-Unity combination commenced solo flight. Future Shuttles would dock to PMA-2 on Unity’s exposed end.

With the next Russian module, Zvezda, delayed by lack of funding from the Russian government, STS-96 in May-June 1999 and STS-101 in May 2000, both with international crews, docked to the Station carrying pressurised SpaceHab modules full of logistics. These modules remained in the Shuttle’s payload bay and were unloaded through the docking system, with a pressurised tunnel giving access to the SpaceHab. Meanwhile, NASA provided additional funding to the Russians, to ensure the completion and launch of Zvezda. In return, the Russians agreed that much of the time that had been allocated for their cosmonauts to perform Russian experiments on ISS would now be spent with those Russian cosmonauts performing American experiments.

Two years later, in July 2000, Zvezda was carried into orbit by a Proton launch vehicle, and completed an automated rendezvous using its KURS guidance system, then docked with Zarya at the opposite end to Unity. This module formed the centre of the Russian segment of ISS. It contained flight control systems, manoeuvring thrusters, life support systems, experiments, and exercise machinery. Zvezda also contained three Soyuz and Progress spacecraft docking drogues, at the wake, nadir, and zenith. Zvezda’s crew quarters, including individual sleeping quarters for two people, allowed ISS to be permanently occupied, in the same manner as the Soviet/ Russian Mir space station that had preceded it.

Once occupied, ISS could be re-supplied by Progress cargo vehicles, and the first, Progress M1-3, was launched in August 2000 and docked to Zvezda’s wake. Individual Progress vehicles were launched by a Soyuz launch vehicle and employed their KURS guidance system to complete an automated rendezvous and docking with Zvezda. In the event that the KURS failed, the crew on ISS could use the TORU controls mounted inside Zvezda to manually guide the Progress to docking. Once docked, internal hatches were opened to allow the crew to unload the dry cargo delivered by the Progress. Propellants, water, and later oxygen were held in tanks in the unpressurised section of the Progress spacecraft and were pumped to the relevant tanks in Zvezda and Zarya. Zvezda’s wake and nadir docking systems contained plumbing to accept Progress-delivered liquids and oxygen. Following unloading of the dry cargo, the pressurised section of the Progress was loaded with rubbish and items that were no longer required on the station. With the hatches closed once more, Progress was undocked and commanded to enter Earth’s atmosphere, where it was destroyed by frictional heating.

In September 2000, STS-106 carried a further SpaceHab double module full of logistics to the station. This was followed by STS-92, in October 2000, which delivered the Zenith-1 (Z-1) Truss. This housed the station’s primary attitude control system, consisting of four 98 kg Control Moment Gyroscopes (CMGs), steel wheels that spun at up to 6,600 revolutions per minute. The combination of their large mass and high rotation rate allowed them to store angular momentum. When the CMG was commanded to “speed up or slow down’’ the resulting force caused ISS to rotate.

The rate of spin was a measure of the momentum that they held; speeding up or slowing down would cause the station to rotate on that axis in response. By the application of multiple CMGs in this manner ISS could either be maintained in orientation, or manoeuvred to a new orientation. When any planned movement of the station’s attitude required momentum beyond that available in the CMGs, rocket motors on Zvezda, or on the Shuttle or Progress cargo vehicles, could be used to provide that momentum. The Z-l Truss also supported a number of communications antennae for NASA’s Tracking and Data Relay Satellites (TDRSs), and served as a temporary mount for PMA-2 during the installation of the next pressurised module and later for storing PMA-3. Progress Ml-З was undocked in October and de-orbited in November 2000.

Expedition crews of three professional cosmonauts/astronauts could now be delivered by Soyuz spacecraft, and the first arrived on Soyuz TM-31 in November 2000. Command of alternate Expedition crews was rotated between American astro­nauts and Russian cosmonauts. When the Expedition crew Commander was an American astronaut the Russians insisted that their cosmonaut serve as Soyuz Commander when the Soyuz spacecraft was in solo flight, which was reasonable. If the Expedition crew was commanded by a Russian cosmonaut then this person served in both roles. Whenever there was an Expedition crew onboard ISS, there was always a Soyuz spacecraft docked to the station, ready to serve as a Crew Return Vehicle (CRV), a lifeboat in an emergency.

Progress Ml-4 was launched in November 2000, and unloaded following docking to Zvezda’s nadir. It was subsequently undocked and re-docked in the same location during December 2000. During the original docking a coating of ice on the spacecraft’s camera had led to a failed automated approach. The undocking and re­docking was to prove that the problem had been resolved. Progress Ml-4 was finally undocked and de-orbited in February 2001.

Figure 1. America’s Space Shuttle was the main cargo haulage vehicle for the major elements in the American sector of the International Space Station. It was launched vertically from Launch Complex 39, Kennedy Space Centre, Florida.

Figure 2. After re-entry through Earth’s atmosphere the Shuttle orbiter approaches the landing strip along a trajectory that is far steeper and faster that a commercial airliner.

The next Shuttle launch was STS-97, at the end of November 2000, which docked to Unity’s ram and used its RMS to install the Port-6 (P-6) ITS on the Z-l Truss. From there, its two Solar Array Wings (SAWs) would provide sufficient electricity to support the initial enlargement of the American sector of ISS. Installing the P-6 and deploying its SAWs required three EVAs by the Shuttle’s crew.

STS-98, launched in February 2001, docked to Unity’s nadir. The Shuttle’s RMS was used to remove PMA-2 from Unity’s ram and mount it on the Z-l Truss. The RMS was then used to lift the Destiny American laboratory module out of the Shuttle’s payload bay and mount it on Unity’s ram. PMA-2 was subsequently retrieved and mounted on Destiny’s ram for use in future Shuttle dockings. Destiny would become the new heart of the station, taking over many of Zvezda’s control operations as well as serving as the principal American scientific laboratory on ISS.

Having docked their spacecraft to Zvezda’s wake, the Expedition-1 crew had to move it to Zvezda’s nadir in February 2001. This cleared Zvezda’s wake for use by Progress M-44, which flew in February 2001. Having delivered its cargo, it carried away rubbish for disposal in April 2001.

While early Shuttle flights had carried their cargos in SpaceHab pressurised modules, which remained in the Shuttle’s payload bay, only cargo that could pass through the narrow circular docking system could be transferred. Later Shuttle logistics flights carried the Italian-built Multi-Purpose Logistics Module (MPLM). This was lifted from the payload bay using the Shuttle’s RMS and docked to Unity’s nadir. Thereafter, large square internal hatches were opened to allow internal access for unloading of bulky items (in particular, racks of equipment to outfit Destiny). Once empty, items to be returned to Earth were loaded into the MPLM, which was then sealed, undocked, and returned to the Shuttle’s payload bay for return to Earth.

The first MPLM, Leonardo, flew on STS-102 in March 2001. That flight also carried the Expedition-2 crew up to ISS and recovered the Expedition-1 crew at the end of their occupation.

The second MPLM, Raffaello, flew on STS-100 in April 2001. That flight also delivered the SSRMS, which was initially mounted on the exterior of Destiny, and was capable of moving end over end to manoeuvre around the exterior of the American sector of the station. It would ultimately be mounted on the Mobile Base System, on the ram face of the ITS, and would be vital to the construction of the outer segments of the ITS itself. The SSRMS was operated by crew members from a work station inside Destiny.

Expedition crew occupations were planned to last from 4 months to 6 months, which was within the operational limit of a single Soyuz spacecraft. Despite this fact, the Russians preferred to replace the Soyuz several months before its 6-month operational life expired. This resulted in Mir-style, 10-day duration, Soyuz “taxi” flights, which delivered a new Soyuz to ISS. These taxi flights were usually flown by two Russian cosmonauts and a paying passenger, either a professional European Space Agency astronaut, or a commercial Space Flight Participant (more commonly referred to as a “space tourist”). The taxi crew returned to Earth in the original Soyuz, leaving the fresh vehicle for the Expedition crew. Soyuz TM-31 was replaced by Soyuz TM-32 in April 2001. This flight was also the centre of much controversy, when the Russians announced that they had contracted to launch the first commercial passenger, an American multi-millionaire, to ISS without clearing their plans with NASA beforehand. Progress M1-6 docked to Zvezda’s wake in May 2001.

STS-104 delivered the Quest Airlock in July 2001. After docking the Shuttle to Destiny’s ram, Quest was lifted out of the payload bay and docked to Unity’s starboard side. Two EVAs from the Shuttle’s airlock and one from Quest itself were required to support the installation of four gas tanks on the exterior of the new airlock. Quest would support EVA by crew members wearing either the American EMU or Russian Orlan-M pressure suits. The following month, August 2001, STS-105 docked to Destiny’s ram and installed MPLM Leonardo on Unity’s nadir for unloading, and re-filling before it was returned to the Shuttle’s payload bay. STS-105 also delivered the Expedition-3 crew and recovered the Expedition-2 crew. Progress M1-6 was undocked from Zvezda in August, and was replaced at Zvezda’s wake by Progress M-45 the following day.

Soviet budget restrictions had long ago caused the cancellation of all remaining Russian ISS modules except one, the Pirs Docking Module-1. This was launched by a Soyuz launch vehicle in September 2001, and carried out an automated rendezvous and docking using a Progress tug, which was jettisoned following docking and burned up in Earth’s atmosphere. Pirs contained a docking drogue for Soyuz spacecraft at its nadir, but it was also an airlock supporting EVA by crew members wearing Russian Orlan-M pressure suits. Two Russian Strela cranes (mechanically driven telescopic booms, extremely low-technology versions of the American RMS and SSRMS) were installed by EVA on the exterior of Pirs, to provide efficient access to the exterior of the Russian sector of ISS.

Progress M-45 was undocked from Zvezda’s wake in November 2001.

Figure 3. A Soyuz-FG launch vehicle lifts off from Baikonur Cosmodrome in Kazakhstan.

Figure 4. A Soyuz spacecraft approaches the International Space Station.

Soyuz TM-33 was a taxi flight to change out the CRV attached to ISS. Launched in April 2001, it docked to Zarya’s nadir. The crew returned to Earth in Soyuz TM-32 a week later. Occasionally, the Expedition crew’s Soyuz CRV would have to be moved from one docking point to another, thus making way for a Progress or a replacement Soyuz at the original docking point. In order to do this, the Expedition Crew had to prepare ISS for automated, uncrewed operations before sealing them­selves in the Soyuz and undocking. After manoeuvring and docking to the new location, the crew would then return to the station and re-activate everything. This long and complicated procedure, which could take up to a week, was used in case it were to prove impossible to re-dock the Soyuz spacecraft, in which case the crew would use it to return to Earth, leaving ISS unoccupied. The Expedition-3 crew followed this procedure before they undocked Soyuz TM-32 from Zarya’s nadir and moved it to Pirs’ nadir in October 2001.

Progress M1-7 flew in November 2001. Although it was able to soft-dock to Zvezda’s wake, the hard-docking was prevented by a rubber seal, debris left behind by Progress M-45 as it left. The Expedition-3 crew made an impromptu EVA to remove the seal, and the Progress was able to hard-dock in December.

STS-108 brought the Expedition-3 occupation to an end in December 2001, when it delivered the Expedition-4 crew to ISS. The MPLM Raffaello was docked to Unity’s nadir for unloading while the two crews carried out their week-long hand-over.

Representatives from several other nations involved in ISS have already flown to the station in orbit and new conflicts have arisen as individual cultures are integrated into the programme. In the coming years both the European and Japanese science laboratories and their unmanned cargo delivery vehicles will be integrated into the programme. They will bring with them their own astronauts, control centres, and management teams, all of which will add to the international melting pot that is the ISS programme. In 2007, China, only the third nation to develop an independent human spaceflight programme, also voiced an interest in becoming involved in ISS. On top of everything, Russia continued to offer commercial flights to ISS to anyone, regardless of nationality, who can afford the $20 million that it costs to buy the third seat on a Soyuz taxi flight. No doubt all of these nations will bring with them a new set of cultural clashes and a new set of lessons to be learnt. They will also bring with them newfound professional respect, both given and received, and newfound personal friendships.

In short, ISS is the most complex spacecraft ever built to support human beings in space. However, just as much as the incredible machinery, it is the clash of national cultures here on Earth, and the requirement for individuals to learn to work together and trust each other implicitly that is at the heart of the ISS programme. In the words of American astronaut Kenneth Bowersox,

“The best thing is we’ve got Americans and Russians and international crews, they’re not just working together they’re actually getting along, making friends, building relationships. That’s the visible part. The part that’s much more impor­tant and not visible is the relationships being built on the ground. I tell people that 95 percent of what’s important about Space Station happens on the ground: when American engineers and Russian engineers get together; when a Canadian meets a Russian and they talk about what life is like in their countries; when we send somebody from Houston over to Japan, and he talks to somebody at dinner. The relationships that we’re building are building a stronger world, and that’s just as important as building our Space Station.’’