Galileo: the causes of the failure of the Fregat become clearer
On October 7, Arianespace will release the report on the failure of the orbit of two Galileo satellites. Its contents, however, already leaked in the press. It's a hardware problem in the Fregat stage which is the cause of a bad path.
The Fregat upper stage is behind the failure of the orbit of the two Galileo satellites. Involved, some of the fuel that would have frozen in midair.
This week that must be made ??public the report of the independent commission of inquiry set up after the last post missed the first two satellites of the operational phase of Galileo (FOC). On August 22, a pitcher Russian Soyuz lifted off from its launch pad from the spaceport with carrying two Galileo satellites. Due to a problem in the Fregat upper stage, the two satellites have not been placed on the orbit circular referred to some 23,200 km from the Earth .
They are now on an elliptical orbit of 25,900 km of height and 13,700 km of perigee . Moreover, they are not on the right orbital plane: 49.68 instead of 56. That said, while these satellites now operate in an orbit unusable for the operation of the constellation, he will be much more useful than you think.
A design flaw in the Fregat
This report has now been already leaked to the press. And if initially a first explanation for the failure of launcher reported a flaw in the software that controls the Fregat upper stage, it seems that the cause is more serious. Indeed, according to the newspaper Le Monde, citing sources close to the investigation, "it's not human error, but a lack of precision in the Fregat scheme design that makes the fuel froze in mid-air ". According to our own sources, the information is quite plausible.
This material dysfunction is much more problematic than a software fault that corrects a simple rewrite of source code. In addition, the investigators found that other floors under construction Fregat had this same defect. Now return to flight is conditioned on the results of this investigation. If it turns out that this is a design problem, this stage could remain grounded for much longer than expected, which will have a negative impact on the launch schedule "of Arianespace, which operates the Soyuz and this floor from the CSG.
However, before imagining all the possible consequences, it is prudent to await the final conclusions of this inquiry.