Soyuz to build European GPS constellation
After years of debate, European countries agreed to fund the Galileo satellite navigation system, which was designed to rival and complement the America's Global Positioning System, GPS, and the Russian GLONASS network. Ironically, Russian-built Soyuz rockets were given the job of delivering all test versions of Galileo satellites into orbit. Soyuz would also fly five missions with a pair of operational satellites each alongside three Ariane-5 ES rockets, carrying four spacecraft during each launch.
Above: The launch sequence of the Galileo IOV mission.
The first launch
On Dec 28, 2005, at 08:19 Moscow Time, the Soyuz-FG rocket with the Fregat upper stage, lifted off from Site 31 in Baikonur Cosmodrome, delivering the GSTB-V/2A satellite for the Galileo global positioning system. The mission, first announced in March 2004, was originally scheduled for Dec. 26, 2005, however it was postponed on the request of the customer.
The second launch
The Soyuz-FG rocket with the Fregat upper stage blasted off from Baikonur Cosmodrome's Pad No. 6, on April 27, 2008, at 02:16 Moscow Time, (22:16 UTC on April 26) carrying a GIOVE-B satellite for Europe's future global positioning system.
Preliminary information showed that the vehicle successfully reached its initial orbit and the Fregat upper stage initiated its maneuvers to insert the satellite into the final orbit. Total three firings of the Fregat upper stage were planned before the separation of the satellite at 29,600-kilometer orbit with the inclination 56 degrees toward the Equator three hours 45 minutes after liftoff.
The mission was previously expected to take place on April 14, Nov. 27, Nov. 30, 2006, and at the end of February 2007. At the end of 2006, the mission was delayed from April 2007, by the failure of the onboard computer. It was further delayed from Dec. 29, 2007, February, March and April 14, 2008.
Preparations for the third mission
In March 2007, the GIOVE-A2 in-orbit validation mission was scheduled to lift off in the second half of 2008 from Baikonur. In January 2010, the mission was promised at the end of 2010. As of March 2010, the launch was delayed to February 2011 as the earliest. In January 2011, the launch was targeted for August 31, 2011, but by mid-March 2011, it slipped to the end of September 2011. By May 2011, the mission was promised in mid-October of that year. On May 23, 2011, the October 20 launch date was announced. Galileo’s second flight model, FM2, touched down in Kourou on Sept. 7, 2011, on an An-124 and the Galileo Protoflight Model followed it seven days later on an Il-76.
On Oct. 10, 2011, Arianespace announced that the integration of the Galileo spacecraft on their dispenser occurred in the Spaceport’s S5 payload preparation facility, where these European-built satellites also had been filled with propellant. In parallel, the Soyuz rocket was undergoing final testing inside its MIK launcher integration building, with the final checkout on schedule for an October 14 transfer to the launch pad.
The first rocket to fly from Kourou emerged from the assembly building on Oct. 14, 2011, at 07:00 local time, moved to the launch pad and was raised to vertical position.
October 20 launch attempt
The mission was postponed on Oct. 20, 2011, just three hours before a liftoff scheduled at 07:34:28 local time (10:34 GMT) due to a technical problem during the fueling of the launch vehicle's third stage. The fueling was stopped, when a leak was detected in one of the valves, requiring its replacement. According to Arianespace, the rocket and its two Galileo satellites, along with the launch facility have been placed in a safe mode and a new launch date will be announced later today. It is believed that at least 24 hour delay would be required.
On the morning of October 20, Arianespace released a statement quoting the company's Chairman & CEO Jean-Yves Le Gall as saying that the leak was in a launch pad pneumatic system that activates the pre-planned disconnection of fueling lines to Soyuz’ third stage before the vehicle lifts off. “During the final phase of third stage fueling, there apparently was a change in pressure in this pneumatic system, and we observed the unplanned disconnection of the two connectors that enable the fueling of Soyuz’ third stage with liquid oxygen and kerosene,” Le Gall told reporters during a briefing at the Spaceport’s Jupiter mission control room. "The problem apparently is due to a valve leak in this pneumatic system, and we have taken the decision to empty the launcher and replace the valve." Le Gall underscored that the identified anomaly is in the ground-based pneumatic system, not on the launch vehicle.
Fueling of the Soyuz is performed inside the mobile service gantry, which continues to remain in place on the launch pad. The launcher and its payload of two Galileo IOV (In-Orbit Validation) satellites were in a safe mode, as is the ELS launch site. Le Gall said a decision was to be made later on that day on whether to reschedule the liftoff for tomorrow. "We will confirm this once the valve is replaced; the decision also will take into account the launch team members – who worked all night during the original countdown." If the launch was to be approved for the next day, the liftoff time would be four minutes earlier – at 7:30 a.m. local time, Arianespace said on October 20, 2011.
Galileo launch sequence (for the second mission in 2011):
The third launch
A Russian Soyuz rocket successfully delivered a pair of European satellites into correct orbit, following its first historic liftoff from a brand-new launch pad in French Guiana. A Soyuz-ST-B vehicle lifted off on Oct. 21, 2011, at 10:30:26 GMT (06:30 EST, 14:30 Moscow Time) Friday, opening a new era in its operations from Kourou, French Guiana. The rocket carried a first pair of four In-Orbit-Validation (IOV) satellites for the European Galileo navigation network. The legendary Russian launch vehicle started its mission after two decades of planning and construction of a brand-new launch complex in South America. The near-equatorial location of the launch facility enables a dramatic increase in the payload mass delivered by a veteran Russian rocket into space, comparing to cargo carried by the same vehicle from similar launch sites in Plesetsk and Baikonur.
The Fregat upper stage was scheduled to deploy its two-passenger payload into their final 23,222-kilometer circular orbit with an inclination 54.7 degrees toward the Equator, where they were to function for 12 years.
After a liftoff from the Guiana Space Center, the flight of the three lower stages of the Soyuz launch vehicle lasted for 9 minutes and 20 seconds. Then, the Soyuz third stage separated from the nose module, consisting of the Fregat upper stage, the satellite dispenser and two Galileo IOV-1 satellites. The three lower Soyuz stages fell back to Earth.
The Fregat upper stage will then fire its own engine, taking the satellites into an intermediate orbit. After this first burn, the Fregat will perform a so-called barbecue maneuver to slowly spin satellites for even out heating of the satellites in space. It will be followed by the release of the satellites.
The Galileo satellites were attached side-by-side to a dispenser developed by RUAG Space Sweden, with a pyrotechnic separation system used to release them in opposite directions three hours, 49 minutes 27 seconds after launch.
The first two Galileo IOV satellites, launched in October 2011, were to be followed by two more in 2012. This quartet of 700-kilogram satellites, built by a consortium led by EADS Astrium Germany, was to form the operational nucleus of the full Galileo navigation constellation. Satellites combine the best atomic clock ever flown for navigation – accurate to one second in three million years – with a powerful transmitter to broadcast precise navigation signals.
Preparations for the fourth launch
The FM3 and FM4 satellites arrived to French Guiana on August 8 and 17, 2012, respectively. At the time, their launch was expected around Oct. 10, however the delay of a preceding Ariane-5 mission required to postpone the Soyuz liftoff by two days. The assembly of the Soyuz rocket for the mission started at the end of April 2012 and processing of the Fregat upper stage at the end of July 2012.
On October 3, a pair of Galileo satellites were integrated on their payload dispenser. The dual-payload dispenser for Galileo was developed by RUAG Space Sweden for Arianespace, and carries the satellites in a side-by-side arrangement. It will deploy the spacecraft by firing a pyrotechnic separation system to release them in opposite directions at the orbital insertion point. The Soyuz ST-B rocket for the mission, designated VS03, was rolled out to the launch pad on October 8. Early on October 9, the pair of Galileo satellites were transferred to the launch pad where they were hoisted up into the MST in preparation for mating with the Soyuz ST-B rocket. In the afternoon, the pair of Galileo satellites were mated to the Soyuz ST-B rocket in preparation for the October 12 launch.
On October 10, launch specialists in French Guiana conducted a full-scale rehearsal that simulated the launch and involved the same teams and communication links to be used during the actual mission. A day later, the mission was cleared for the actual liftoff. At the time, both Galileo IOV spacecraft were activated for their useful operational lifetimes of approximately 12 years, Arianespace announced.
The VS03 mission marked the return to flight mission for the RD-0124 engine following the December 2011 launch failure. The engine for this mission was modified to comply with interagency failure board's recommendations and increase its reliability. Following the modification process, the engine for this mission successfully completed two full duration test firings for verification tests before the engine (including stage three) was flown back to Guiana for final processing.
The European launch services consortium Arianespace launched the fourth mission to build the continent's satellite navigation system with the help of a Russian-built launch vehicle.
The Soyuz ST-B/Fregat-MT rocket lifted off on Oct. 12, 2012, from its recently completed equatorial launch pad in French Guiana at 15:15:01 local time (18:15 GMT, 22:15 Moscow Time). It is carrying a second pair of In-Orbit Validation satellites (FM3 and FM4) for Europe's Galileo navigation satellite constellation. Around 10 minutes after the liftoff, the Fregat upper stage and its payload separated from the third stage of the launch vehicle and initiated its first engine burn during a planned three-hour, 30-minute orbital insertion mission.
Along with two previously launched spacecraft, the latest pair of satellites will form the minimum coverage required for satellite-based navigation – providing latitude, longitude and altitude data, while also checking ranging accuracy. As a result, these In-Orbit Validation Galileo satellites were to enable European industry to validate prototype Galileo-based receivers and services against actual satellite signals, while also allowing performance assessments of Galileo’s ground system that serves to maintain the Galileo system’s precision.
The IOV spacecraft were produced in a European industry consortium led by the Astrium division of EADS and Thales Alenia Space. A total of 24 Galileo satellites were yet to be launched by 2015, with six additional Soyuz vehicles carrying two spacecraft each, along with three Ariane-5s configured with four per launch.
Above: Soyuz lifts off with the first pair operational Galileo satellites on Aug. 22, 2014.
Above: Artist rendering of the operational version of Galileo satellite.
A Russian-built rocket left a pair of European navigation satellites in a wrong orbit Friday. A Soyuz-ST-B rocket lifted off as scheduled from the ELS launch pad in Kourou, French Guiana on August 22, 2014, at 16:27:11 Moscow Time (8:27 a.m. EDT, 12:27 GMT, 9:27 a.m. local time). The launch vehicle carried two 730-kilogam Galileo FOC M1 satellites, where FOC stands for the Full Operational Capacity.
The launch seemed to be flawless, however at the end of the day on August 22, Arianespace, which managed the mission, announced that "complementary observations gathered after separation of the Galileo FOC M1 satellites on Soyuz Flight VS09 have highlighted a discrepancy between targeted and reached orbit. Investigations are underway. More information will be provided after a first flight data analysis to be completed on August 23, 2014."
Radar observations showed that three objects from the launch were in a 13,720 by 25,920-kilometer orbit with an inclination 49.7 degrees toward the Equator. Galileo FOC M1 No. 5 and No. 6 satellites (a.k.a. Doresa and Milena) were the first of 22 operational satellites scheduled to be inserted into a 23,522-kilometer orbit with an inclination 55.04 degrees toward the Equator.
The European Space Agency, ESA, then announced that "following the announcement made by Arianespace on the anomalies of the orbit injection of the Galileo satellites, the teams of industries and agencies involved in the early operations of the satellites are investigating the potential implications on the mission. Both satellites have been acquired and are safely controlled and operated from ESOC, ESA's Operations Centre in Darmstadt, Germany. Further information on the status of the satellites will be made available after the preliminary analysis of the situation."
Peculiarly, during the live coverage launch, observers noticed wrong speed readings displayed along the visualizations of the launch. It seemed that its altitude parameters were fed into the speed channel. Speed parameters were dropped from screen during later part of orbital insertion. Still, all reports from mission control confirmed normal flight and the Arianespace declared the mission success shortly after the separation of the satellites.
Multiple independent sources analyzing the situation suggested that the Fregat upper stage had fired its engine for the right duration, however the stage's orientation in space during the second or both maneuvers had probably been wrong. According to Jonathan McDowell, an astronomer at the Harvard-Smithsonian Center for Astrophysics and a veteran space historian, the Fregat's angular orientation error during the engine firing could reach as much as 145 degrees.
According to industry sources, an investigation commission was formed in Moscow to look into the botched launch. Sources at RKTs Progress, the developer of the Soyuz rocket, and NPO Lavochkin, the developer of the Fregat upper stage, indicated that telemetry from the launch had showed normal performance of their respective systems.
The liftoff and first part of the mission proceeded nominally, leading to release of the satellites according to the planned timetable, and reception of signals from the satellites. It was only a certain time after the separation of the satellites that the ongoing analysis of the data provided by the telemetry stations operated by the European Space Agency (ESA) and the French space agency CNES showed that the satellites were not in the expected orbit.
The targeted orbit was circular, inclined at 55 degrees with a semi major axis of 29,900 kilometers. The satellites are now in an elliptical orbit, with excentricity of 0.23, a semi major axis of 26,200 km and inclined at 49.8 degrees.
Both the Fregat upper stage and the two satellites are in a stable condition and position that entails absolutely no risk for people on the ground. The residual propellants on the Fregat stage have been purged and the stage was depressurized normally.
According to the initial analyses, an anomaly is thought to have occurred during the flight phase involving the Fregat upper stage, causing the satellites to be injected into a noncompliant orbit.
Studies and data analyses are continuing in Kourou, French Guiana, and at Arianespace headquarters in Evry, near Paris, under the direction of Stéphane Israël, Chairman and CEO of Arianespace, in conjunction with the Russian partners in the Soyuz in French Guiana program (Russian space agency Roscomos and the manufacturers RKTs Progress and NPO Lavochkin, as well as Arianespace's customer ESA and its industrial partners, to determine the scope of the anomaly and its impact on the mission.
"Our aim is of course to fully understand this anomaly," said Stéphane Israël, Chairman and CEO of Arianespace. "Everybody at Arianespace is totally focused on meeting this objective. Starting Monday, Arianespace, in association with ESA and the European Commission, will designate an independent inquiry board to determine the exact causes of this anomaly and to draw conclusions and develop corrective actions that will allow us to resume launches of Soyuz from the Guiana Space Center, CSG, in complete safety and as quickly as possible. The board will coordinate its work with Russian partners in the Soyuz at CSG program. Arianespace is determined to help meet the European Union's goals for the Galileo program without undue delay. We would like to thank ESA, the European Commission and CNES for the very productive discussions since becoming aware of the occurrence of the anomaly. While it is too early to determine the exact causes, we would like to offer our sincere excuses to ESA and the European Commission for this orbital injection that did not meet expectations."
The Moscow-based investigation commission into the Galileo launch accident was expected to convene for the first time on Monday (August 24). As of August 24, all publicly available data from the flight pointed toward a wrong orientation of the Fregat upper stage during its second engine firing, which led to the However whether it was caused by the faulty attitude control system, or by its software or by some failure during the flight remains a mystery. Peculiarly, the telemetry from the flight control system on the Fregat apparently indicated flawless performance of all systems.
By August 25, several reliable posters on the Novosti Kosmonavtiki web forum indicated that the attention had quickly focused on two out of 12 small thrusters that are used to keep the Fregat upper stage in right orientation during unpowered flight and also place it in correct attitude for the firing of the main engine. It seems that the firing of two thrusters was interrupted, even though they had received all the correct commands from the flight control system. As a result, the Fregat started its second main engine firing in the wrong direction, causing the change in the orbital inclination toward the Equator, instead of boosting its altitude.
The role of the flight control system in failing to detect or report this problem to ground control remains unclear.
The Fregat is equipped with 12 thrusters fed from a common hydrazine fuel distribution line. Four such thrusters are used to control the roll of the stage during the powered phase of the flight (when the main engine fires).
Following the major anomaly that occurred on August 22, 2014, during the Soyuz ST mission carrying two satellites in the Galileo constellation, Arianespace announced today, in conjunction with the European Space Agency
The commission is chaired by Peter Dubock, former ESA Inspector General. Its mandate is to establish the circumstances of the anomaly, to identify the root causes and associated aggravating factors, and make recommendations to correct the identified defect and to allow for a safe return to flight for all Soyuz launches from the Guiana Space Center (CSG).
The commission will start its work on August 28, 2014, and submit its initial conclusions as early as September 8, 2014.
The inquiry commission comprises the following members:
To maintain links with the Russian partners in the Soyuz at CSG program, the head of the Russian space agency Roscosmos, on request from the head of Arianespace, has designated Alexander Daniliuk, Deputy Director General of TsNIImash, as board liaison.
Arianespace Chairman and CEO Stéphane Israël said: "I would like to thank Peter Dubock for having accepted the chairmanship of this commission, which was appointed in conjunction with ESA and the European Commission and with the support of the space agencies from France (CNES), Germany (DLR) and Italy (ASI), along with a team of high-level European experts. The commission will now be able to carry out its work independently, operating
Also on August 25, Johann-Dietrich Woerner, the chairman of the German space agency, DLR, published an account of the failure. "The first problem became apparent when the two satellites proved unable to deploy their solar arrays as intended. A more detailed analysis then revealed that the eccentricity, the altitude and the inclination of the satellites' orbits with respect to Earth's equator did not meet specifications."
According to Woerner during its passive flight in the period between two engine firings, Fregat had failed to initiate the planned rotation around the longitudal axis of the spacecraft known as the barbecue mode. It is usually conducted to ensure even heating of the spacecraft by the Sun.
However Russian industry sources said that according to the telemetry from the Fregat upper stage, the barbecue mode had been implemented as planned. Still, it was not possible to immediately confirm that the rate of rotation was correct and its axis was pointed in the right direction to ensure that all sides of the spacecraft are evenly heated by the Sun.
One unlikely failure scenario that observers discussed on the Novosti Kosmonavtiki forum involved premature deployment of solar panels on Galileo satellites, which could dramatically shift the center of gravity of the Fregat/Galileo stack and result in its wrong orientation. However, the fact that the satellites were designed to be inactive during their ride on Fregat makes this hypothesis very unlikely. In addition, it would not explain the apparent interruption in the work of attitude control thrusters onboard Fregat.
Other scenarios for changing the orientation of Fregat could include some unexpected jet force that could affect the stage, such as sudden evaporation of ice from the surface of the vehicle.
Work at ESA’s ESOC control centre continues relentlessly on the two Galileo satellites.
Despite the non-nominal orbit, the satellites are safely under control after they were released from the launcher upper stage and their orbital position was determined by the European ground teams deployed at ESOC in Darmstadt, Germany.
Controllers there, in cooperation with the satellite manufacturer OHB, confirm the good health and the nominal behaviour of both satellites. A procedure to deploy the solar arrays that had remained partially folded on both satellites was successfully executed on the first satellite in the course of Monday night. A similar procedure will be executed soon on the second satellite.
Both satellites continue to be kept in a safe state, correctly pointing to the Sun, properly powered and fully under control of the ESA/CNES integrated team and the teams of OHB deployed at ESA’s control centre
In parallel, the teams are investigating the possibilities to exploit the satellites to their best despite the non-nominal injection orbit and within the limited propulsion capabilities of the satellites.
By August 28, specialists familiar with the operation of the Fregat upper stage and with basic details of the investigation had been able to discern a rough sequence of events that had likely led to the failure of the Soyuz mission with Galileo satellites last week. As it turned out, the so-called barbecue mode (a rotation of the Fregat stage to even out heating of the satellites by the Sun) is always preceded by a special "re-orientation" maneuver. It is designed to prevent sensitive mechanical gyroscopes onboard the stage from stalling. Such a re-orientation is conducted individually for each of three axises with a certain angular speed and over a certain time period.
It appears that during the delivery of Galileo satellites on August 22, at the very end of the re-orientation routine, the flight control system detected a wrong angular speed and sent commands to Fregat's thrusters to correct the situation. For a yet unknown reason, engines failed to achieve that, even though available telemetry confirms that electric valves activated the thrusters as directed. Specialists are still debating what force or abstraction could prevent the thrusters from doing their job in the emptiness of space or whether firing engines somehow did not deliver required thrust.
To make matters worse, the flight control system also perceived that thrusters had worked and thus failed to recognize that they did not provide correct parameters to the Fregat. Instead, the flight control system completed all "re-orientation" maneuvers within the assigned time and concluded that the stage was in correct attitude to continue its mission.
Beyond this short period of time, there were no deviations from the flight program. Unfortunately, it was enough to begin the following "barbecue" mode with wrong orientation of the stage toward the Sun. Even worse, when the time came to fire the Fregat's main engine for the second time, the stage was pointing in a wrong direction. Surprisingly, to highly intelligent computers onboard Fregat everything looked normal.
It seems that a coincidence of several small glitches led to the overall failure of the mission. According to European officials, there was little chance that the Galileo FOC M1 satellites could be used for their intended purpose. Both spacecraft would need twice as much hydrazine propellant onboard to reach their target orbit.
It was the ninth launch of the Soyuz rocket from French Guiana and the mission is known as VS09 in the flight manifest of Arianespace, that operates the Russian-built rockets based in Guiana along with Europe's own Ariane-5 and Vega rockets. At the time of final preparations for the FOC M1 mission, another launch with Galileo satellites was scheduled for the last quarter of 2014.
The operational Galileo satellites were built by a prime contractor OHB System, while their payloads were supplied by SSTL (Surrey Satellite Technology Ltd), a British subsidiary of Airbus Defence and Space.
On Jan. 26, 2010, Arianespace announced signing of a contract for five Soyuz missions to deliver pairs of Galileo FOC satellites.The first of these launches was previously delayed from December 2012 to the second half of 2013.
The first attempt to launch Galileo FOC M1 mission on August 21, 2014, was scrubbed less than eight hours before the liftoff scheduled for 16:31:14 Moscow Time (8:31 a.m. EST) due to bad weather. The Russian space agency, Roskosmos, then posted a press-release announcing that the mission was rescheduled for Aug. 22, 2014, at 16:27:11 Moscow Time (8:27 a.m. EST, 12:27 GMT). However Arianespace said that "another launch date will be decided depending on the evolution of the weather conditions in Kourou." By the end of the day, Arianespace reported that "a favorable trend in weather conditions is forecasted for tomorrow over the Guiana Space Center, Europe’s Spaceport. Therefore, Arianespace has decided to restart the countdown..."
Flight scenario of the FOC M1 mission.
Above: Artist rendering of the separation between Galileo satellites and a Fregat upper stage.
Galileo launch sequence (for the FOC M1 mission):
A complete list of launches in the Galileo constellation:
Galileo satellites IOV-1 PFM (Protoflight Model) and FM-2 (second flight model):
This page is maintained by Anatoly Zak with contributions from George Chambers
Last update: August 30, 2014
Galileo satellites inside the payload section of the Soyuz-ST-B rocket. Credit: ESA
Artist rendering of the Fregat-MT upper stage maneuvering Galileo satellites into their final orbit. credit: ESA
Artist rendering of In-Orbit-Validation (IOV) satellites IOV-1 PFM (Protoflight Model) and FM-2 (second flight model) launched on Oct. 21, 2011. credit: ESA
An early mockup of the GSTB V2 satellite designed by EADS Astrium for testing systems of the Galileo constellation. Copyright © 2005 Anatoly Zak
An opertional version of the Galileo satellite, as it was envisoned in 2005. On Jan. 26, 2010, Arianespace announced a contract for five Soyuz missions to deliver operational satellites for Europe's Galileo navigation network beginning in 2012. Copyright © 2005 Anatoly Zak
The 2009 depiction of the Galileo satellite proposed by OHB Systems. Copyright © 2009 Anatoly Zak
A model of Galileo satellite displayed at Paris Air and Space Show in June 2011 and in 2009 (top). Copyright © 2011 Anatoly Zak
The most stable space-based atomic clock ever developed for practical operation was reportedly designed for Galileo satellites. Built by Selex, PHM promised outstanding stability for averaging times from 1 to 100,000 seconds, to be used in precise positioning, time keeping and other onboard applications designed to perform in space for not less than 12 years. Copyright © 2010 Anatoly Zak
Soyuz lifts off with two Galileo satellites on Oct. 12, 2012. Credit: Arianespace
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Soyuz lifts off with the first pair operational Galileo satellites on Aug. 22, 2014. Credit: Arianespace