An independent Chinese board of inquiry investigating the Aug. 31 underperformance of the Long March 3B rocket is expected to deliver its conclusions by mid-November, with the possibility that the vehicle will be returned to flight as early as late this year, China Great Wall Industry Corp. officials said Sept. 8.

In interviews here during the World Satellite Business Week conference organized by Euroconsult, China Great Wall officials said the Long March 3B placed Indonesia’s Palapa-D telecommunications satellite into a too-low orbit when one of its two identical upper-stage engines failed to deliver the necessary thrust.

They said the engine did not shut down. Instead, for reasons the inquiry board has been assigned to determine, the motor operated at a lower-power level during its second ignition.

Palapa-D builder Thales Alenia Space has recovered the satellite and on Sept. 9 announced that the spacecraft had been placed into final geostationary position using its own thrusters. Thales Alenia Space Chief Executive Reynald Seznec said Sept. 9 the satellite has enough onboard fuel remaining to provide 10 years of full service, or two-thirds of its 15-year contractual lifetime.

China Great Wall Industry Corp. Vice President He Xing said the board of inquiry is composed of people who have no direct involvement in the design of the rocket. He said the results would be made available to customers and to the global satellite-insurance community as soon as they are available.

Two identical motors power the upper stage of the Long March 3B rocket. The same stage is used for the Long March 3A and Long March 3C vehicles, meaning that these, too, will be grounded pending the results of the inquiry.

China Great Wall officials said the upper stage has flown more than 25 times without incident, suggesting that it is not a design issue that caused the Aug. 31 malfunction. “But the truth is we will let the inquiry board make the determination,” He Xing said. “For now, we don’t know what they will find. They will have complete freedom in their work.”

Another China Great Wall official said the company hopes that, if the failure is traced to a straightforward workmanship issue, the vehicles can be cleared to return to flight as early as the end of this year.

Peter B. de Selding was the Paris bureau chief for SpaceNews.