European Commission Likely To Commit to up to Six More Galileo Craft
KOUROU, French Guiana — A senior European Commission official on March 27 said the commission is determined to have 30 Galileo positioning, navigation and timing satellites in orbit by 2020, implicitly endorsing the expenditure of 200 million to 300 million euros ($220 million-$330 million) to purchase four to six more spacecraft this year or next.
Daniel Calleja Crespo, the commission’s director-general for internal market, industry, entrepreneurship and SMEs, also said the commission is now confident that two Galileo satellites sent into a wrong orbit in August can be integrated into the Galileo constellation.
Calleja, speaking at Europe’s spaceport here in advance of the launch of the 7th and 8th Galileo satellites aboard the same Europeanized Russian Soyuz-Fregat rocket that caused the August problem, said one launch glitch is unimportant when set against the goal of Galileo.
“In the minds of many remains what happened in August,” Calleja said. “Yes, we had an anomaly and a setback. But we remain determined. We are building a system to assure European autonomy, and we are helping build an industrial base for Europe.”
The August launch was of the first pair of 22 Galileo satellites under contract to OHB SE of Bremen, Germany, with the electronics payloads built by SSTL of Guildford, England.
In addition to these, four in-orbit validation satellites were launched in 2011 and 2012, both on Europeanized Soyuz rockets. But these satellites have an apparent antenna anomaly that has effectively taken one of them out of service.
That being the case, the commission will need to order between four and six new satellites this year or early next year to assure that, by 2020, 30 satellites — 24 operational spacecraft and six in-orbit spares — have been launched.
In a briefing here, European Space Agency officials said the two bad-orbit satellites, both of which have been moved to more-acceptable orbits, have demonstrated their ability to be used in the overall Galileo constellation with minimal effect on performance, and virtually no noticeable effect to users.
“The impact on users is what counts,” said Didier Faivre, ESA’s director of navigation. “At this point, we think the orbit will delay the initial acquisition by users by about 30 seconds in the worst case, whereas it should be just a few seconds. And because the orbit is a bit lower than we wanted, there will be a 5-10 percent reduction in the satellites’ availability.”
To achieve this result, ESA — with the blessing of the commission, which owns Galileo — will need to invest no more than around 5 million euros to modify Galileo’s elaborate ground infrastructure.
ESA and the commission had hesitated before accepting the use of these two satellites, fearing that adapting the ground network might cost as much as building and launching two new satellites, or around 100 million euros.
The fact that this now appears unnecessary relieves budgetary pressure at the commission.
“Let’s be clear,” Faivre said. “We still have some issues. We did not foresee this orbit, so we have, in the navigation language, some difficulties in putting together the almanac, meaning the forecast of future orbits. And due to the orbit’s eccentricity [the satellites were supposed to be placed in a circular orbit], there is a variation in the speed that produces Doppler effects.”
Nonetheless, he said, tests of the two bad-orbit satellites with the three functioning validation spacecraft show that Galileo’s positioning and timing accuracy is on a par with “the very best in the world, meaning the U.S. GPS.”
Assuming a successful launch of the latest pair of Galileo satellites — the satellites were awaiting launch at press time — ESA and the commission have scheduled the launch of another pair of spacecraft in September, with the following launch in December or January.
Faivre said OHB is producing satellites at a rate of two every three months. The next two have already left OHB for environmental testing at ESA’s Estec center in Noordwijk, Netherlands.
Faivre said ESA has submitted a procurement proposal to the commission to decide the timing, number of spacecraft and procurement route — a new order with OHB or a competitive bid process with other builders — for the new spacecraft.
Javier Benedicto, ESA’s Galileo project manager, said the agency has approved a software patch to be uploaded to the three healthy in-orbit-validation satellites that should provide advance warning if any of them show the same antenna-related issues as the fourth.
He said it may be possible to arrest the performance degradation with enough warning.
In an indication of how concerned it was after the August launch — space industry officials said the commission overreacted to the problem — the commission has now decided to purchase insurance for the Galileo satellite launches starting in September. The commission had previously insured all Galileo launches, but only to cover the cost of a new launch in the event of failure. The new policy will cover the satellites themselves.