Failure of weld seam may have caused Proton crash

Published: 9/6/1999

The Failure Review Oversight Board, organised by International Launch Services and Lockheed Martin, to consider the findings of the Russian Commission's Proton launch failure investigation, has issued its preliminary statement on the crash that occurred on 5th July 1999. The report describes a malfunction beginning with the failure of a weld seam holding a turbine cover in place. This changed the flow and led to a fire within the turbine. The condition may have been caused by the presence of microparticles introduced during the fuelling process. The Oversight Board was presented with telemetric, analytic and test data collected during the course of the Russian failure investigation. It was also permitted to examine the actual turbopump hardware that failed during the flight, which had been recovered from the debris impact area in Kazakhstan. The corrective action plan involves taking additional measures to ensure the quality of the weld, and improving the filtering of propellants to preclude the introduction of microparticles. Based on its review and analysis of the provided information, the Oversight Board supported the decision to return the Proton launch vehicle to flight. It also recommended the resumption of commercial spacecraft shipment, processing and launch operations on the Proton, following the mandatory completion of the initial group of corrective actions proposed for the forthcoming LMI-1 launch. The go-ahead to ship LMI-1 to Baikonur has been now been given, based upon the Board's preliminary statement. The launch of LMI-1 is presently targeted for 26th September 1999.

Article ID: 834