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The Zvezda module reaches launch pad During the first half of 2000, the Russian space agency, Rosaviakosmos, raced against the clock to prepare the long-delayed Zvezda Service Module for launch. In addition to finishing the testing of this super-complex and expensive spacecraft which would become the cornerstone of the International Space Station, ISS, the cash-strapped industry had to resolve the latest technical problems with its Proton launcher, while also juggling an overloaded flight manifest and being under the political "rock and hard place" on two sides of the Atlantic.
The Zvezda Service Module rolls out to the launch pad on July 8, 2000.
Resolving engine problem After two Proton rocket failures in 1999, investigators determined that a production flaw in the second-stage engines manufactured in 1992 and 1993 was the culprit. Although none of the Protons slated for flights in 2000 had engines older than two years, the rocket's prime contractor, GKNPTs Khrunichev, could not afford to take any chances with the particular vehicle intended for the launch of the Zvezda Service Module. The priceless spacecraft was assigned to a rocket with the newest version of the second and third-stage engines and Russian space officials wanted at least two Proton rockets to fly successfully with the modified engines, before certifying them for carrying the Zvezda. The Zvezda launch set for July 12 After a series of meetings in Russia in early 2000, the partners in the International Space Station project, ISS, officially set the launch date for the Zvezda Service Module, SM, for July 2000. The Russian, European and US space officials met in Moscow on February 10, 2000, to review the status of the $60-billion project and agreed that the Zvezda would be launched during a window from July 8 to July 14. On Friday, February 11, 2000, the latest launch window was formally confirmed during the meeting of the Chief Designer Council at RKK Energia in Korolev, near Moscow. Around 350 space officials were present, including a 40-member team of experts from the US. The Chief Designer Council, originated at the dawn of the Soviet rocket program, was traditionally responsible for the crucial decisions within the industry. According to Yuri Grigoriev, Deputy Designer General at RKK Energia, Russia's prime contractor in the ISS project, the Zvezda launch date was dictated by the latest forecast for lighting conditions during the docking of the Zvezda module with already launched elements of the ISS. The optimal conditions for the launch of Zvezda would be on July 12, Grigoriev said. If the July launch window was to be missed, the second opportunity would come in August 2000. After 15 days in the autonomous flight, Zvezda and the ISS were to meet in orbit, with the Russian-built Zarya FGB module performing active maneuvers to complete the automatic docking. According to Kyle Herring, the spokesman at Johnson Space Center in Houston, NASA was very confident that Zvezda would launch in July. However, the launch was contingent on the successful tests of the upgraded Proton engines, which in early 2000 were yet to be validated for carrying the Zvezda. "It has always been dependent on the Proton, the module itself is essentially ready," Herring said in early February. At the time, the Proton remained grounded by a launch failure on October 27, 1999 and its return to flight was scheduled for February 12, 2000. According to sources in Moscow and Houston, NASA still planned the launch of its Space Shuttle on April 13, 2000, for the second so-called "outfitting" flight (Mission 2A.2a) to the nascent ISS, then comprised of the Zarya FGB and the US-built Unity module. The follow-on Shuttle flight to the station was expected to take place after Zvezda was docked to the ISS. Originally, only one outfitting Shuttle mission (2A.1) had been planned, however, delays with the Zvezda launch and the deterioration of several systems aboard Zarya prompted NASA to add another visit to the ISS into the Shuttle manifest in 2000, almost a year after the first outfitting mission was completed in June 1999. Political and economic problems During meetings in Moscow in early 2000, RKK Energia officials assured NASA that the company would be able to supply one Soyuz crew vehicle and two Progress cargo ships for the ISS operations in 2000. NASA expressed concern that a recent decision by the Kremlin to extend the life of the Mir space station would impair RKK Energia's ability to supply the spacecraft for the ISS. For the ISS operations, one Soyuz spacecraft (Vehicle No. 205, which was eventually used for the Soyuz TM-31 mission) was a standby mode in Baikonur for a contingency trip to the ISS in the unlikely case of problems preventing the automatic docking between Zarya and Zvezda. If the modules linked up as planned, that Soyuz would remain on the ground until October 2000, when it would carry the first long-term expedition to the ISS. A Progress cargo ship was also slated to go the ISS soon after the Zvezda arrival, with the primary mission of delivering propellant for the station. "We promised to have one Soyuz and one Progress spacecraft ready, by the time Zvezda launches in July," Grigoriev said. NASA also requested an extra Progress flight to the ISS, for which RKK Energia did not initially have enough funds. As of early 2000, RKK Energia had around a dozen spacecraft in its shops in various stages of assembly. However, the company struggled to receive money from the government to maintain the necessary pace of production. Final preparations for launch In April 2000, Valeri Alaverdov, the first deputy director general at Rosaviakosmos, who was attending the launch campaign at Cape Canaveral for the Space Shuttle's 2A.2a visit to the ISS, re-confirmed one more time that Russia would meet the July 12 launch date. Tommy Holloway, the ISS program manager at Johnson Space Center echoed Alaverdov saying that he was confident Zvezda would take off between July 8 and 14. The upgraded engines for the Proton rocket, which were to carry Zvezda, arrived at Khrunichev plant in Moscow on April 1, 2000, and the fabrication of the rocket was expected to be completed around May 15, 2000. On May 28, 2000, Khrunichev was scheduled to ship the rocket to the Baikonur Cosmodrome. As of April 2000, Rosaviakosmos planned two launches of the Proton rocket with upgraded second-stage engines before the Zvezda launch. Alaverdov said that the first Proton with modified engines was scheduled to fly around May 18 or 19, carrying the Gorizont-45 communications satellite. Khrunichev was preparing to ship the Proton rocket for that launch on April 26. In case of success, another launch to validate Proton’s upgraded engines would take place in the second half of June 2000. This time, the rocket was expected to carry a Geyzer data-relay satellite for the Russian Ministry of Defense. Launch calendar
The Zvezda Service Module is being prepared for integration with its protective fairing at Site 254 in July 2000. Although the Zvezda service module was reported to be all but ready for flight in the final months leading to the July 12 launch attempt, Russian engineers continued last-minute work on the spacecraft. The most important final upgrade was related to the module’s software. The new computer code for the Zvezda’s flight control system was designed to improve the survivability of the spacecraft should communication with the ground break down. According to the latest work plan worked out by April 2000, the electrical testing on Zvezda was to be completed on April 29. Following the May Day holidays, the module would go through a four-day test in vacuum chamber, kicking off a 60-day cycle of final preparations for launch. Around May 20, 2000, members of early expeditions aboard the ISS were scheduled to visit Baikonur for familiarization training inside the Service Module. The Zvezda was scheduled to reach the critical preparation milestone around June 16, 2000, when project officials had to make the final commitment to the July 12 launch. The decision would give the go ahead to the so-called irreversible operations, such as fueling of the spacecraft with toxic and highly corrosive propellants. This critical operation was scheduled for June 27. Around July 3, the fully assembled Zvezda and its protective shroud were to be mated to the Proton launch vehicle and the whole system would then be rolled out to the launch pad for final processing. Station crews to visit their future home Several US astronauts and Russian cosmonauts were scheduled to leave Moscow for Baikonur on May 22, 2000, for an inside-and-out familiarization session with the module, in the procedure known as the Crew Equipment Interface Test, CEIT. At the time, the Zvezda module was still inside the processing building at Site 254 in Baikonur, but during the week of May 19, some critical tests of the module, including leak checks in the vacuum chamber, had already been completed. The cosmonauts and astronauts, who participated in the CEIT activities, represented four different crews preparing for work on the ISS:
During two sessions planned between May 22 and 26, 2000, the astronauts and cosmonauts were to familiarize themselves with both exterior and interior of the module. Following the training, the module was to through final integration and it was to be mated with its launch vehicle on July 3. Zvezda leaves Area 254 After spending more than a year inside the processing building at Site 254 of the Baikonur Cosmodrome, the Zvezda Service Module, enveloped into its protective shroud, was transferred to the center's then only active fueling station at Site 31 on Monday morning, July 3, 2000. The fueling became a crucial milestone in the almost decade-long preparation of this spacecraft for launch. After loading toxic hypergolic propellants into the Zvezda's tanks, its lengthy storage on the ground was becoming extremely difficult, therefore the operation was considered irreversible in the spacecraft’s launch processing. The Russian space officials made the decision to wait with the fueling until the modified Proton rocket – the same type as the one to be used for the Zvezda launch – flied a successful test mission on July 5. This was the second and final launch needed to qualify the upgraded engines on the Proton rocket. While they were under development for years, the modified engines were hastily rushed into service specifically ahead of the Zvezda launch. The first launch of the Proton rocket with modified engines was completed successfully on June 6, 2000. Officials scheduled the start of fueling the Zvezda for around 6 or 7 a.m. Moscow Time on July 5, right after the preliminary analysis of the launch a few hours earlier was to confirm that the Proton’s first three stages functioned flawlessly. The original schedule called for the fueling between July 3 and 4, 2000, however, a delay of the second Proton launch with the modified engines pushed back the fueling operations and narrowed Zvezda’s launch window which originally extended from July 8 to July 14. Several requirements were known to determine Zvezda’s launch window:
In order to make up some lost time, on July 4 and 5, ground processing teams in Baikonur planned to connect fueling lines to Zvezda’s tanks and make sure they were sealed. The engineers also planned to test the operation of vacuum pumps which were to be used to remove air from the fuel lines. The fueling itself was planned to be executed under very tight deadlines to allow the in-time transfer of Zvezda to the launch vehicle integration building on July 6, 2000. Another 30 hours were allocated to the integration of the module with its Proton rocket. On July 7, the fully assembled Proton rocket with the Zvezda module was scheduled to roll out to the launch pad for final checks before launch on July 12, 2000. The second Proton rocket with the modified engines on the second and third stage lifted off from Baikonur, on July 5, 2000, carrying a Geyzer military relay satellite. Soon after the launch, the Russian media reported that the engines on the second stage of the booster experienced some anomaly which could lead to an accident. Nevertheless, after evaluating the problem, Russian space officials decided to proceed with the on-time preparation for launch of the service module. Zvezda rolls to the pad The Proton rocket with the Zvezda service module rolled out to the launch pad in Baikonur Cosmodrome on Saturday, July 8, 2000. Traditionally for this Russian launch site in Kazakhstan, the more than 40-meter rocket with the Zvezda module under its nose fairing left the assembly building No. 92-1 at 6:30 a.m. local time, shortly after sunrise. Moving on its rail transporter, the rocket reached launch pad No. 23 at Site 81 at 8:10 a.m. local time. The entrance into the launch complex read “completed in 1964,” marking the first of four launch pads for the Proton rocket in Baikonur. Despite strict security at the gates of the launch complex, numerous observers greeted the rocket at the pad. Some put coins on rails to be smashed by the rocket train -- another old tradition of the cosmodrome. In the next few hours, special mechanisms were used to prop the rocket into vertical position and lower it onto the launch pad. The service tower then moved in and completely enveloped the rocket into an array of access balconies. The launch personnel used the structure to inspect the rocket and its payload. Anatoly Kiselev, Director of Khrunichev enterprise, the manufacturer of the launcher, and Yuri Semenov Director of RKK Energia, responsible for the Zvezda service module, showed up at the launch pad soon after the rocket's arrival with a large entourage. They told the crowd of reporters that everything was in perfect shape for the July 12 launch. “There are no issues,” Kiselev said. “We are one hundred percent ready,” Semenov echoed him. The officials said that in the next day and a half, a team from RKK Energia was scheduled to conduct the final inspection of the module and then it was up to the military personnel at Site 81 to complete preparations for launch. According to the Russian Aviation and Space Agency, Rosaviakosmos, the launch of the Zvezda service module was scheduled for July 12, 2000, at 10:56:28 local time. (The launch time was apparently pushed back by eight seconds during planning for the mission.) The autonomous tests of the vehicle had taken place on the pad on July 9, 2000, followed by integrated tests a day later, clearing the mission for launch.
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