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History of the ATV project Origin of the program Soon after its decision to participate in the US Space Station program, the European Space Agency, ESA, had ordered a study aimed at determining the design and capabilities of a specialized maneuverable space tug which would support the orbital outpost. Although the American Space Shuttle and the European Hermes reusable space planes were expected to deliver and return most of the space station supplies, an unmanned expendable vehicle seemed to be a better choice for the task of carrying some payloads or for disposing of trash. From the outset, the scale of the future cargo ship was based on the capabilities of the then yet-to-be-built Ariane-5 rocket. This powerful vehicle was expected to carry 16.4 tons of cargo into low Earth orbit, however a specialized vehicle was needed to maneuver and dock Ariane-5's cargo to the space station. Appropriately, the future space tug was initially dubbed Ariane Transfer Vehicle, ATV. (It would be later identified as Automated Transfer Vehicle.) The ATV would be installed on top of the Ariane-5 rocket, instead of the standard upper stage, known as L5, which would be used for Ariane's routine task of boosting communications satellites. Originally designers envisioned the ATV space tug to be fully compatible with a variety of different payloads, including space station modules, cargo containers and satellites. Upon reaching the space station, the ATV would be picked up by the outpost's robotic arm and moved to a special parking area. There, the spacecraft would wait to be loaded into the cargo bay of the Space Shuttle for return to Earth or for a docking with a trash container and a subsequent destructive plunge into the Earth atmosphere. After analyzing a chosen flight mode, developers came up with a list of requirements toward the design of the ATV ship:
As of 1987, the ATV development was expected to take around five years and the ship would reach launch pad soon after the introduction of the Ariane-5 rocket in mid-1990s. At the time, the development cost of the project was estimated at $100-150 million, and each vehicle was expected to have a price tag of $30-40 million. (272) In 1995, a ministerial conference in Toulouse, France, officially approved European involvement in the ISS program with the Columbus laboratory and ATV vehicles. A customized version of the Ariane-5 rocket, designated A5/ES, designed to carry ATV into orbit was also authorized for development. Russian involvement In 1995, after Russia joined the space station project, the European Space Agency asked RKK Energia, Russia's prime developer of manned spacecraft, to evaluate the possibility of using the ATV spacecraft within the Russian segment of the outpost. At the time, Daimler Benz Aerospace, DASA, served as prime contractor in the ATV project. Under contract with DASA, in 1996, RKK Energia issued reports on the possibility of equipping the ATV with a station-refueling system, similar to the one used on the Progress cargo ship. RKK Energia also looked at the installation of special laser reflectors on the station's service module, designed to assist in docking. In the middle of 1996, ESA transferred the role of ATV prime-contractor from DASA to the French company Aerospatiale. By the middle of November 1996, based on Aerospatiale's "Permission to initiate development" RKK Energia studied several aspects of the program:
The tele-operator mode would enable an astronaut onboard the station to take the ATV through a final phase of docking using a special TV camera and a joystick-like control panel onboard the station. A similar system was first introduced onboard the Mir space station and was added to the ISS' "docking arsenal," as a backup, in case, the primary automated docking system failed. By 1997, RKK Energia also added oxygen, nitrogen and water-delivery systems to the ATV capability list. The company also proposed to install a dedicated Russian-made control panel to monitor all the Russian hardware onboard the ATV. Space station partners also agreed to give the ATV the ability to undock and do formation flying with the station. Such autonomous flight could last up to two months, freeing the docking port on the service module for incoming traffic, consisting primarily of smaller but more frequently launched Progress cargo ships. To enable long-duration autonomous flight, the future ATV spacecraft was upgraded with power-generating solar panels. As of 1997, ATV development was to be completed by 2002. However, during 1998, the Russians and the Europeans clashed over the cost of the project. ESA rejected the price tag tabled by the Russians in exchange for their services, delaying the final agreement on ATV development. To save money, ESA dropped a TV channel from the ATV's docking hardware. As a result, the station crew lost its ability to use the TORU remote control system, to dock the cargo ship to the service module. In September 1998, the Russians and the Europeans finally reached a general agreement on the integration of the ATV into the Russian segment. After a series of additional negotiations, on July 9, 1999, the two sides signed a contract on cooperation in the ATV development. MBRL communication system To establish communications between flight control computers onboard the ATV and the Russian segment, the two partners developed a so-called Inter-board Radio Channel, or MBRL. It included RKK Energia-developed antennas and European avionics. RKK Energia originally planned to install most of the MBRL antennas and avionics on the Universal Docking Module and Science and Power Platform within the Russian segment. However, by 1999, after learning about the dismal funding situation in Russia, ESA officials were convinced that these two Russian modules had no chance of flying before the ATV did. As a result, the partners scrambled to install MBRL avionics and related cables onto the service module, while it was in the final stages of preparation for launch. The Russians still reserved the option of moving this hardware to the Universal Docking Module, if it ever made it to the station. At the same time, the antennas from the MBRL complex were left to spacewalking astronauts to install, after the service module had reached the orbit. RECS docking and refueling control system Designers on both sides had to walk another torturous path in the development of the flight control system for Russian equipment onboard the ATV. Known as RECS, this hardware was in charge of all Russian-built docking and refueling systems. According to the original plans, RECS had to be able "to talk" to all main and peripheral flight control computers onboard both the cargo ship and the service module of the station. An alternative "smart" RECS system featuring its own computer was proposed. During 1999, once again the Russians and the Europeans struggled to balance the desirable sophistication of the RECS system and the mounting cost of its development. Only in December 1999, did the two sides generally agreed on the simplified RECS, with no "brain" of its own, but with an avionics box, capable of converting analog parameters. A motherload of problems If previous struggles had not been enough, in the second half of 1999, European space officials "surprised" their Russian partners with a requirement for all Russian systems onboard the ATV to withstand the launch loads of the Ariane-5 rocket. As it turned out, Russian hardware was certified for launch only onboard the smaller, gentler Soyuz rocket which exerted several times less loads in some parameters. Early on, a number of Russian officials treated the issue as insignificant and failed to document it properly. Now, ESA demanded from the Russians that they fix the problem at their own expense. After a series of negotiations between December 1999 and February 2000, the Russians agreed to subject mockups of their ATV hardware to Ariane-5-compatible loads, but at ESA's expense. The cost was initially estimated at almost 0.9 million Euro. However the very first such test conducted in March 2000, caused damage to one element of the propellant line in the refueling system. Additional studies were needed. When the Russians sent the Europeans a six-million Euro estimate for the entire array of tests and resulting upgrades, it caused shock at ESA headquarters. Despite all these disagreements, development work did continue. In May 2000, a series of negotiations on the conditions of future work produced a number of breakthroughs. On July 21, 2000, RKK Energia and the Italian firm Alenia signed a contract for the supply of Russian systems for the ATV vehicle. (164) Although the development of the ATV vehicle was moving forward, its first launch was dependent on the progress of the space station construction. Designed to support European activities onboard the Columbus laboratory, the ATV remained grounded along with it for years, waiting its turn in the interdependent station assembly schedule. The ATV program did have its critics, who said the spacecraft was oversized and overpriced comparing to its Russian counterpart -- the Progress cargo ship -- which carried less cargo but could be launched more frequently, thus providing more flexibility to ISS operations. However when in 2004, the US government made a rather abrupt decision to retire the Space Shuttle in 2010, the ATV's lifting muscle suddenly came very handy.
The ATV development chronology: Mid-1980s: Studies of the European cargo ship to support space station start. 1995 October: A ministerial conference in Toulouse, France, officially approved European involvement in the ISS program with the Columbus laboratory and ATV vehicles. 1995: The European Space Agency asked RKK Energia, Russia's prime contractor in the space station project, to evaluate the possibility of using the ATV spacecraft within the Russian segment of the outpost. 1996: RKK Energia issued reports on the possibility of equipping the ATV with a system for refueling the space station, similar to the one used on the Progress cargo ship. Mid-1996: ESA transferred the role of ATV prime-contractor from DASA to the French company Aerospatiale. 1996 August: Aerospatiale and RKK Energia started negotiations on a new ATV development contract. 1998 September: Russians and Europeans struck a deal on the integration of the ATV into the Russian segment. 1998 Oct. 21: Roskosmos Deputy Director General A. I. Medvedchikov and RKK Energia President Yuri Semenov sent a letter to ESA outlining rights and responsibilities of the Russian and European partners in the ATV project. 1998 November: ESA signs contract with the EADS Launch Vehicles industrial conglomerate for the development of the ATV spacecraft and the integration of the first version of the ship. 1999 July 9: Russian and European officials signed a contract on cooperation in the ATV development and its integration into the Russian segment of the station. 1999: Aerospatiale added a forward cluster of attitude control thrusters into the design of ATV, improving the maneuverability of the ship. 2000 May 15-29: At Aerospatiale, the first phase of the ATV project approval took place. 2000 July 21: RKK Energia and the Italian firm Alenia signed a contract for the supply of Russian systems for the ATV vehicle. 2000 December: The second phase of the ATV project approval took place. 2001 November: A full-scale test model of the ATV, the Structural Thermal Model, STM, is integrated at ESA's ESTEC center in Noordwijk, Netherlands. (274) 2002 end of year: An Electrical Test Model, ETM, consisting mostly of the cable harness and the avionics of the ATV, was installed at Astrium plant in Les Mureaux, France, for test and qualification campaigns. 2004 July: ESA signs contract with EADS Astrium to produce operational versions of the ATV spacecraft. 2005 January: Technicians at ESA's research center in Noordwijk, the Netherlands, including ESA astronaut Jean Francois Clervoy entered inside the vertically positioned ATV, Jules Verne, in order to simulate the late loading of cargo bags. 2005 March 2: The Russian Progress M-52 cargo ship delivered hardware to the station needed to integrate the ATV spacecraft into the Russian segment of the station. 2005 March 28: During a spacewalk outside the station, NASA astronaut Leroy Chiao and Russian cosmonaut Salizhan Sharipov installed a Global Positioning System receiver. The device is part of the ATV communications hardware designed to give the approaching vehicle data about its relative position to the station during rendezvous operations. 2006 July: Acoustic testing of the first ATV ship, was completed at ESA's test facilities in Noordwijk, Netherlands. 2006 Nov. 23: Two Expedition 14 crew members conducted a 5-hour, 38-minute spacewalk outside the station during which they relocated a WAL antenna, designed to guide the ATV to docking with the station. At the time, the ATV was scheduled to make its first flight in 2007. In its previous position the antenna interfered with a cover on a booster engine of the Zvezda service module. 2007 July 28-30: The ATV spacecraft and its S5C upper stage arrive to the launch site in French Guiana. (273) 2007 Oct. 5: The qualification review for the ATV is successfully completed. 2008 Feb. 15: The ATV spacecraft is integrated with its Ariane-5 launch vehicle. (273) 2008 March 1: Dress rehearsal of the ATV launch. (273) 2008 March 3: ESA announced the postponement of the scheduled launch of the ATV vehicle from March 8 to March 9. A minor technical glitch required opening the payload fairing of the Ariane-5 rocket, covering the ATV spacecraft, resulting in a 24-hour delay. 2008 March 7: After a several-hour delay by minor technical problems, the Ariane-5 rocket with the ATV spacecraft rolled out to its launch pad in Kourou, French Guiana. 2008 March 9: The ATV-1 lifts off and successfully reaches orbit.
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