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Galileo Launch Anomaly
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23-08-2014 5:22pm#1
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I forgot about this. The problem was traced to a fuel line installed to close to a Helium line. Seemingly a common thing as the same installation was found on other Soyuzs but the coast time in between burns on this rocket was enough for the line to freeze. Highlights below.
A Europeanized version of Russia’s Soyuz rocket placed two European navigation satellites into the wrong orbit in August because its hydrazine fuel line was installed too close to a supercold helium line on the Fregat upper stage, European government officials said.
The installation caused the hydrazine to freeze long enough to upset the Fregat stage’s orientation and cause the two satellites’ release into an orbit that is both too low and in the wrong inclination, officials said.One official said the Euro-Russian board of inquiry into the failure discovered that one in four Fregat upper stages at prime contractor Moscow-based NPO Lavochkin had the same fuel-line installation.
The board of inquiry is expected to release its findings the week of Oct. 6.
“We have to assume that this was a practice that had gone on in perhaps a quarter of the Fregat stages produced in the past decade, but that it had not affected our launches up to now because of mission-specific aspects like coast time between burns, the number of burns and so on, which can influence the effect of the helium on the hydrazine,” this official said.One industry official said the installation glitch was not a workmanship error insofar as the Fregat design manual did not recommend that the helium and hydrazine lines be separated. It was left to each installation team to do as it wished.
Government and officials said the commission is debating how to proceed now that it knows that, as expected, the Fregat failure was not one of design, but of assembly and quality control.Government and officials said the commission is debating how to proceed now that it knows that, as expected, the Fregat failure was not one of design, but of assembly and quality control.
The options are to continue, as scheduled, with the December launch of two more Galileo satellites aboard a Soyuz Fregat rocket, or to wait until next spring or summer and launch four Galileo satellites on a heavy-lift Ariane 5 vehicle.
Not in the link above is an Israeli startup Effective Space Solutions, has said that it could, in theory, build a small satellite that would latch onto the two Galileo satellites and drag them to the intended orbit.The company's robotic design would use an ion thruster — rather than conventional rocket fuel — to slowly but efficiently manoeuvre them.
Jonathan McDowell, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, says that back-of-the-envelope calculations suggest that the craft proposed by Effective Space Solutions could carry enough ion fuel to do so. But McDowell cautions that autonomous docking of spacecraft is a complicated engineering challenge for a company with no track record. “I’m very sceptical of this particular company doing it — even though it seems like they might have a good idea,” he says.
No such trouble for the Indians who are now near half way (3 of 7 Sats Up) in building their own GPS Network.
3rd on the way o/
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