ILS Clears Proton/Breeze-M for Next Flight in March

Proton-M launch on December 8, 2012.  (Credits: Khrunichev).

The Failure Review Oversight Board (FROB) of the International Launch Services (ILS) concluded its review of the anomaly on the Yamal 402 Proton launch, convening with the Russian board of inquiry on the root cause, on February 7.“My sincere appreciation goes out to our customers, insurance underwriters and independent subject matter experts for their thorough and diligent participation in the ILS FROB process.  We thank our customers for their support as ILS Proton proceeds towards return to flight,” said ILS Vice President of Programs and Operations John Palmé.

The FROB analyzed the findings and recommendations from the Russian working group, agreeing on the cause and the associated corrective plan.  The most probable root cause of the failure, which occurred on December 8 2012, was due to a combination of “adverse conditions”.  These troubles affected the operation of the Breeze-M main engine during the start of the 3rd burn causing damage to a bearing on the oxidizer side of the turbo pump.  This led eventually to a failure of the bearing during the 4th burn causing Breeze-M to end its final burn about 4 minutes early, with subsequent automatic separation of the commercial spacecraft in the wrong orbit. With the upper stage deploying Yamal 402 into the incorrect orbit, the satellite was commanded to use its own propulsion system to reach its operational position in geostationary orbit, 35,900 km over the equator.  However, the spacecraft spent more fuel than originally planned, reducing its calculated lifetime from 15 years to 11 years.

The Yamal 402 launch failure marked the 3rd problematic Proton/Breeze-M launch since August 2011.  Previously, the launch of 2 communications satellites had failed due to a component within the Breeze-M’s pressurization system on August 6, 2012.  Previous to that, another Breeze-M had failed to deploy a satellite due to a programming error, on August 16, 2011.  However, ILS officials stressed that the Yamal 402 anomaly did not share commonality with the previous failures.

The ILS Proton return-to-flight mission will be the Satmex 8 communications satellite for Mexican operator Satmex in March.  The launch of the Anik G1 communications satellite for the Canadian Telesat will follow in April.