Eutelsat’s W3B was declared a total loss on October 29th following the loss of thruster fuel from an oxidiser tank. The satellite will probably be deliberately de-orbited over the Pacific Ocean early this week. However, there are now suggestions that the damage to the satellite was caused on the ground prior to launch.
The Arianespace launch on October 29th was described at the time as flawless when W3B was placed into a conventional transfer orbit prior to using the satellite’s own on-board fuel to gently raise itself to full geostationary orbit. W3B was intended to replace three aging satellites at 16 degrees East.
The satellite was built by Thales Alenia Space, and Emmanuel Grave, its VP responsible for Telecommunications Satellites, told trade newspaper Space News that the leak in the oxidizer tank seemed too large to have escaped notice as the satellite was being prepared for integration into the Ariane 5 rocket (and alongside Japan’s BSat-3b satellite, which was launched successfully at the same time). That would suggest that the reservoir was somehow damaged after it was placed under the Ariane 5 ECA rocket’s fairing, alleged Space News.
Grave declined to speculate on what might have happened between that time and the moment W3B was released in orbit, saying a board of inquiry would be established to review the telemetry from W3B and from the Ariane 5 rocket.
W3B carried 53 Ku-band transponders as well as 3 Ka-band transponders. It is likely to be de-orbited into the Earth’s atmosphere. The leakage was said to be so severe as to be insufficient to ensure positioning to a more conventional ‘graveyard’ orbit above its planned Geo orbit.
The original mission would have seen W3B replace three satellites in orbit: EuroBird 16, W2M and Sesat 1. Each of the three have useful life left ahead of them, and will now stay in orbit.
As with every launch it is wise to have a Plan B in place in case of catastrophe, and Eutelsat’s back-up plan will see W3C fill the role of the lost W3B. W3C is slated for launch mid-2011 aboard a Chinese ‘Long March’ rocket. Eutelsat says it will immediately start planning for a fast-track build of W3D, likely to be ready for launch early in 2013. W3C has a matching specification to W3B, and also has Thales Alenia as its prime contractor.
Michel de Rosen, CEO of Eutelsat Communications, commented: “The loss of W3B is a disappointment for Eutelsat and for our customers. We share it with our partners, in particular Thales Alenia Space and with the insurance community. Our attention is now focused on delivering the W3C satellite to 16° East in mid-2011 and on initiating a new programme to compensate for this loss.”
Eutelsat is fully insured for the investment in W3B, which guarantees that the Group does not incur any direct financial loss. The non-availability of W3B does not change the financial guidance issued by the company on July 30th 2010.