Arianespace Begins Inquiry, Soyuz Launches Suspended

A pair of navigation satellites launched last week by Arianespace from its spaceport in French Guiana failed to reach their proper orbits, prompting the formation of an investigative committee to look into the launch.

The satellites were being carried by a Soyuz ST rocket. According to a statement from Arianespace, 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 an incorrect orbit.

On Monday, Arianespace announced the appointment of an independent inquiry commission in conjunction with the European Space Agency (ESA) and the European 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, 2014 and submit its initial conclusions as early as September 8, 2014.

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.

Inside GNSS reports that it is believed that the satellites will never reach their intended orbit. One source told Inside GNSS that it would be unlikely that another Arianespace Soyuz launch would occur before March or April next year.

FMI: www.arienespace.com, www.esa.int