Experts representing the Galileo Program provided a frank and open update on how it is addressing the problem of the first two full operational capability (FOC) satellites being delivered to the wrong orbit. The presentation was part of the panel discussion “Status of GPS, GLONASS, Galileo, BeiDou, and QZSS” at ION GNSS+ Wednesday morning.
No one from Rocosmos attended to present information on the status of GLONASS. A Russian spokesperson had hoped to come but could not obtain a visa, for unknown reasons. There appear to be no Russians at the conference apart from one CEO of a Russian receiver manufacturing firm.
A new article in Nature magazine provides additional background on the Galileo FOC anomaly. Also, the CANSPACE listserv has been engaged in discussing the issue.
An inquiry board is looking into problem to find the root cause of the anomaly. The board has already met several times.
An intermediate report is due shortly; a final report and recommendations will come next month.
The European Space Agency (ESA) is considering what can be done with the two satellites; ESA hopes to be able to use them operationally as much as possible.
ESA is also looking at the impact on the commercial Galileo service and the search-and-rescue service.
ESA is already narrowing down the possible causes of the anomaly.
ESA is waiting for the enquiry board to report before deciding on when and how the next two satellites will be launched.
The payloads of the errant satellites are currently off.
ESA wants to try to raise the perigees of the satellites to get them out of the van Allan radiation belt as soon as possible to prevent damage to the satellites. Raising the perigrees will also to reduce the maximum Doppler frequency shift from 9.6 kHz to at least 6.8 kHz to allow receivers to easily acquire and track the satellites, but leave enough hydrazine for future station keeping.
ESA is looking at the almanac problem and whether unused bits in the Galileo navigation message might be able to support a special almanac for the satellites.
ESA is also looking at possible rephasing of the satellites to optimize their use with the other satellites in the constellation.
“Following the failure on Friday August 22nd to inject Galileo satellites 5 and 6 into the correct orbit, the European Commission has requested Arianespace and the European Space Agency (ESA) to provide full details of the incident, together with a schedule and an action plan to rectify the problem.”
This is the only official face showing, but extremely high levels of activity take place behind the curtain, studying what might have caused several million Euros of hardware to end up much lower above the Earth than desired. Meanwhile, active speculation in the satnav blogosphere provides glimpses of possible outcomes from the latest satellite disaster — not exclusive to Galileo, by any means — created in all likelihood by a malfunction aboard its Soyuz launcher and/or the Fregat upper stage thereof.
The full official EC announcement is available here.
The satellites are under the control of the European Space Operations Centre (ESOC), ESA’s main mission control center in Darmstadt, Germany. But they are far out off position — more than 3,500 kilometers of space away, so far as to make their eventual use as part of the Galileo constellation very unlikely. Discussions continue with ESA and Arianespace regarding whether or not the satellites are likely to be of use, but odds are against it.
Their onboard fuel is not enough to compensate for the launch shortfall to reach higher orbits under their own power. ESA scientists are studying how they might still possibly be used, far from their optimum position,s within the Galileo constellation.
According to an Arianespace press release on August 23, the target orbit was circular, inclined at 55 degrees with a semi-major axis of 29,900 kilometers, but what they got was an elliptical orbit, eccentricity of 0.23, semi-major axis of 26,200 kilometers and inclined at 49.8 degrees.
On August 28, the Russian newspaper Izvestia reported that “The failure of the European Union’s Galileo satellites to reach their intended orbital position was likely caused by software errors in the Fregat-MT rocket’s upper-stage.”
“The nonstandard operation of the integrated management system was likely caused by an error in the embedded software. As a result, the upper stage received an incorrect flight assignment, and, operating in full accordance with the embedded software, it has delivered the units to the wrong destination,” an unnamed source from Russian space Agency Roscosmos was quoted as saying by the newspaper.
An independent inquiry panel has been set up by Ariane. It is headed by former ESA Inspector General Peter Dubock. It starts work on August 28. The panel includes a couple of academics and a majority of ESA and EC figures.
Ferdinando Nelli Feroci, the new EC Commissioner for Industry and Entrepreneurship.
The new EC commissioner in this area, Ferdinando Nelli Feroci has invited ESA and Arianespace to his study during the first week of September to present the initial results of the inquiry.
The commissioner commented, “The problem with the launch of the two Galileo satellites is very unfortunate. The European Commission will participate in an inquiry with ESA to understand the causes of the incident and to verify the extent to which the two satellites could be used for the Galileo programme. I remain convinced of the strategic importance of Galileo and I am confident that the deployment of the constellation of satellites will continue as planned.”
The commissioner expects that the Galileo constellation will be fully deployed by the end of this decade. This may qualify as optimism because system planners had envisioned for six spares – and three are already blown.
Ariane and ESA did not insure the satellites.
According to back-of-the-envelope calculations, system operators are now one short of the minimum 24 needed for full 24/7 global coverage, as they have 4 IOVs up (1 broken) and 22 FOCs on order (2 launched and now in what could be called a junk orbit) which makes a potential maximum 23 sats that have actually been ordered – one short of the target.
The Satellites Are Alright
Satellite manufacturer OHB Systems of Bremen, Germany, issued a release stating that “Controllers at ESA’s ESOC control centre in Darmstadt, Germany, confirm the good health and the nominal behaviour of both satellites. They are in a safe configuration, are thermally stable, have stable pointing to the sun and sufficient power production. All platform subsystems have been checked and they work properly. Also the procedures to deploy the solar arrays are successfully performed and all solar arrays are properly unfolded.”
Further, “The orbit anomaly has no impact on the production and delivery of the in total further 20 satellites. Two FOC*-satellites are currently at ESTEC test facilities in Noordwijk, the remaining are in various status of integration. ”
Blogging the Boondoggle
The chairman of the Executive Board of the German Aerospace Center, Johann-Dietrich ‘Jan’ Wörner, writes an interesting blog. The current installment opens with a quote from Elon Musk: “Rockets are tricky.”
Wörner goes on to say, “The Soyuz launcher lifted off from the European Spaceport in French Guiana. Initially, all of the measurements suggested a perfect mission; the launcher took off at the scheduled time, followed the prescribed trajectory, and the stage separation was carried out correctly. However, 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 the specifications. The upper stage had also evidently failed to induce the planned rotation around the longitudinal axis of the spacecraft (known as ‘barbeque’ mode, designed to maintain favourable thermal conditions during exposure to the Sun).”
Further discussion of the possible causes of the anomaly can be found on a Russian site, which focuses on the Fregat stage thrusters and indicates that the Russians think the barbeque maneuver was completed, and thus not the problem.
The other big issue is how the telemetry didn’t pick up the issue straight away.
There is avid speculation and a number of interesting theories being aired on the Canadian Space Geodesy Forum. For subscriptions to this vital listserv, visit here.
Galileo satellites 5 and 6 are safely under control, despite having been released on a lower and elliptical orbit instead of the expected circular orbit on August 22. Each satellite’s set of solar arrays is fully deployed and generating power, and operations continue smoothly.
The European ground teams deployed at the European Space Agency’s (ESA) control centre ESOC in Darmstadt, Germany, in cooperation with satellite manufacturer OHB, confirm that both satellites are in a safe state, correctly pointing to the sun, properly powered, and fully under control of the ESA-CNES integrated team.
Controllers are ready to proceed to the next stage of the launch and early operations phase activities.
In parallel, ESA teams are investigating the possibilities of exploiting the satellites to maximum advantage, despite their non-nominal injection orbits and within the limited propulsion capabilities. Different scenarios will then be assessed before decisions are taken for a recovery mission, according to ESA.
After the separation of the two Galileo satellites launched August 22, ongoing analysis of the data provided by the telemetry stations operated by the ESA and the French space agency CNES showed that the satellites were not in the expected orbit.
An independent inquiry commission was appointed August 25 by Arianespace, the European Space Agency (ESA) and the European Commission to investigate the anomaly.
Following the major anomaly that occurred on August 22 during the Soyuz ST mission carrying two satellites in the Galileo constellation, Arianespace announced today, in conjunction with the European Space Agency (ESA) and the European Commission, the appointment of an independent inquiry commission.
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 and submit its initial conclusions as early as September 8.
The inquiry commission comprises the following members:
Peter Dubock, former ESA Inspector General, Chairman;
Professor Guido Colasurdo, University of Roma “Sapienza”, full professor of flight mechanics;
Michel Courtois, former ESA Technical Director;
Paul Flament, European Commission, Head of Unit, Galileo and Egnos Programmes Management, DG for Entreprise and Industry;
Giuliano Gatti, ESA, Galileo Program Technical Officer;
Professor Wolfgang Kubbat, former head of the Institute of Flight Systems and Automatic Control at the Technical University of Darmstadt;
Isabelle Rongier, CNES Inspector General;
Toni Tolker Nielsen, ESA Deputy Inspector General.
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 under a very tight schedule. We sincerely hope that the commission’s recommendations will lead to a rapid resumption of missions, while ensuring the high reliability expected of our Soyuz launches from CSG.”
After the separation of the two Galileo satellites launched August 22, 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.
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.
The liftoff and first part of the mission proceeded nominally, reports Arianespace, leading to release of the satellites according to the planned timetable, and reception of signals from the satellites. However, 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 no risk for people on the ground. The residual propellants on the Fregat stage have been purged and the stage was depressurized normally.
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 Lavotchkine), as well as Arianespace’s customer ESA and its industrial partners, to determine the scope of the anomaly and its impact on the mission.
Following the announcement made by Arianespace on the anomalies of the orbit injection of the Galileo satellites, ESA said that 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.
“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.”
New NORAD element sets from Sunday confirm that the satellites and the Fregat upper stage are in the wrong orbits:
During the European Space Agency (ESA) audio press conference held Wednesday morning in advance of Thursday’s launch of two Galileo satellites, there was extended discussion on the problem with the fourth in-orbit validation or IOV satellite (FM4 or GSAT0104 with PRN code E20). The satellite suffered a power anomaly on May 27 as previously reported by GPS World.
The root cause of the problem has still not been identified despite looking at more than 40 possible failure scenarios so far. ESA has conducted extensive analyses of telemetry from the satellite as well as reviews of pre-launch tests. It has been determined, however, that the E5 and E6 frequencies have had a permanent loss of power. E1 appears to be OK and can be switched back into normal operation at any time. Currently, the satellite is transmitting on E1 but using a non-standard test code.
It was also revealed that FM2, the second IOV satellite, suffered a power drop of 2 dB about a year ago, and FM1, the first IOV satellite, has also seen a power drop. In the case of FM1, the problem is in the primary solid-state power amplifier, and there is a plan to switch shortly to the back-up unit. However, there doesn’t appear to be a common-mode of failure relating the power losses on the various satellites.
While the FM4 anomaly investigations are ongoing, the power on all of the IOV satellites has been backed off 1.5 dB.
Concerning the two full operational capability or FOC satellites to be launched tomorrow, ESA is not yet revealing into which orbit plane and slots the satellites will be placed. Nor are they saying yet which pseudorandom noise codes will be used by the satellites. Once the satellites are launched into their preliminary orbits, it will take about two weeks for them to drift to their assigned locations. At that time, we should be able to deduce their locations using, for example, United States Strategic Command (USSTRATCOM) tracking data. And once they begin transmitting standard PRN codes, all-in-view receivers, such as those participating in the International GNSS Service Multi-GNSS Experiment, will be able to identify their codes.
The satellites will undergo testing for 73 days, after which they will be declared operational. ESA intends to use the passive hydrogen maser clocks on the satellites as the primary clocks, with the rubidium clocks used as back-ups.
In an update to our July 2 story (recapped below), correspondent Peter de Selding wrote in Space News on July 3 that the trouble aboard the fourth in-orbit (IOV) Galileo satellite arose from a sudden, unexpected loss of power. The power outage flashed on May 27, shutting down the satellite’s E1 signal. The signal “re-established itself almost immediately. But as soon as it was back in service, the two other channels’ power dropped and did not recover. The full satellite then was shut down by ground teams,” reported de Selding.
European Space Agency (ESA) officials stated on July 3 that they would power-on the satellite again sometime this week (July 7–11) to continue investigating the problem. That investigation has been ongoing since the shutdown but has not identified a cause; officials state they have established that it is not related to the onboard atomic clocks.
The four IOV satellites currently aloft differ in both technology and manufacturer from the next phase of Galileo satellites to be launched. Two of these newer generation are at the Guyana spaceport awaiting a possible late August lift date.
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July 2 GPS World story:
Galileo GSAT0104, the fourth in-orbit validation (IOV) satellite, has been set “unavailable until further notice” according to the European GNSS Service Centre. International observers (not associated with the European Space Agency, ESA) including those of the International GNSS Service tracking the satellite have not detected a signal from GSAT0104 since May 27. A constellation update appeared June 26 at www.gsc-europa.eu/system-status/Constellation-Information, and is reproduced here.
Speculation by unofficial sources is mounting that something is wrong with the satellite, in particular with its passive hydrogen maser, used for timing the signal for synchronous transmission with other Galileo satellites. The hydrogen maser has “a known problem” according to one source. This is why the web site shows GSAT0104, also known as FM04 and E20, as currently using a rubidium atomic frequency standard.
No statement has been made by the ESA.
According to reports, the root cause of the outage is under investigation. Some unofficial sources have gone so far as to speculate that GSAT0104’s useful transmission life may be over.
The setting of unavailability may be due to in-orbit validation testing, as the website implies may be the case, but no further official statement has appeared. On May 27, an active user notifications (NAGU) appeared at www.gsc-europa.eu/system-status/user-notifications regarding GSAT0104 stating ” Unavailable from 2014-05-27 until further notice.” On June 26, another NAGU appeared for “All” satellites and stating “potential performance degradation.” A footnote states “The Galileo system is undergoing its in-orbit validation campaign. During this campaign of tests, users may experience periods of signal degradation.”
According to the ESA website, “The Galileo satellites carry two types of clocks: rubidium atomic frequency standards and passive hydrogen masers. The stability of the rubidium clock is so good that it would lose only three seconds in one million years, while the passive hydrogen maser is even more stable and it would lose only one second in three million years. However this kind of stability is really needed, since an error of only a few nanoseconds (billionths of a second) on the Galileo measurements would produce a positioning error of metres which would not be acceptable.”
Tim Reynolds is director of Inta Communication Ltd. and a long-term Brussels observer writing on many aspects of European government policy and implementation for a range of clients and publications. He is the contributing editor for GPS World’s new quarterly e-newsletter, EAGER: the European GNSS and Earth Observation Report. Subscribe free at env-gpsworld-integration.kinsta.cloud/subscribe.
After the separation of the two Galileo satellites 
