International Launch Services (ILS) which handles the marketing and sales of Russia’s Proton launch rocket has concluded its Failure Review of the May 16th failure of the Proton rocket. The May 16th problem involved an ILS client, Mexico’s Centenario mobile communications satellite. The Proton rocket system has been grounded since the problem.
ILS, in a statement August 3rd, says the Review Board have conducted their investigation and also examined the results of the Russian Interagency Commission investigation which looked at rocket builder Khrunichev and its subsidiary companies and suppliers.
“Based on the data presented by Khrunichev, the FROB agreed that the most probable cause of the failure was a result of a higher than expected vibration environment most likely caused by the combination of a marginal mechanical joint used to mount the Stage III steering engine turbo pump and a steering engine turbopump rotor material that had marginal strength under maximum operating environments. This led to a premature shutdown of the turbopump and loss of Stage III control authority and subsequently to the failure of the mission during 3rd stage operation approximately 497 seconds after liftoff.”
“The participating customers, insurance underwriters and independent subject matter experts are to be commended for their valuable contributions during the extensive FROB review process. We thank our customers for their support as we prepare for the safe return to flight of ILS Proton,” said ILS VP/CTO, John Palmé.