Proton Breeze M Ready To Return to Flight

[Satellite Today – 6-17-08] Just three months after failing to launch the AMC-14 satellite, the Proton Breeze M launch vehicle has been cleared to return to flight, International Launch Services (ILS) said June 16. ILS said the Failure Review Oversight Board (FROB) convened by ILS had cleared the Proton Breeze M to return to flight this summer, following its examination of test results and analysis regarding a redesigned engine component.
    With two launch failures in the last year involving the Proton Breeze M vehicle, the pressure is on ILS now to perform a series of successful launches with the launch vehicle. It can certainly ill afford another failure in the near future after a tough few months. The latest launch failure took place in March this year when ILS failed to successfully launch the AMC-14 satellite for SES Americom. In September last year, the Proton launch vehicle also failed to put the JCSAT-11 satellite into orbit for Japanese satellite operator, JSAT.
    In terms of corrective actions, ILS said a Russian State Commission had investigated the failure, analyzed possible scenarios and reviewed the processes, hardware and systems related to the engine and its supporting systems. Both the Proton booster and the Breeze M upper stage are built by Khrunichev Space Center, which is the primary shareholder of ILS. On April 21 the commission announced its conclusions: that the failure was caused by a ruptured exhaust gas conduit, which led to a shutdown of the turbo pump feeding the Breeze M engine. The commission recommended a number of corrective actions, with the primary step being Khrunichev’s replacing the existing conduit with a thicker-walled conduit.
    ILS assembled an independent FROB to review the Russian commission’s findings in early May. Khrunichev subsequently performed additional modeling as well as component and certification engine testing to determine root cause and validate the recommended corrective actions. The FROB reconvened in Moscow last week to review the analysis and test results. The FROB agreed that the root cause of the failure was that the conduit walls were thinner than the minimum specification, which when combined with other factors led to the rupture.