U.S. FAA says plans careful look at Orbital report on rocket blast

By Andrea Shalal COLORADO SPRINGS, Colo. (Reuters) - The U.S. Federal Aviation Administration will carefully review an Orbital ATK-led investigation into an October rocket explosion to ensure that all possible causes were properly considered, a top FAA official said Wednesday. "We eagerly look forward to seeing what they have to say and making sure we understand it and agree with it before allowing them to go ahead with future launches," George Nield, associate administrator for commercial space transportation, told Reuters after a speech at the annual Space Symposium conference. Orbital and enginemaker GenCorp Inc offered competing explanations on Tuesday for what caused the Oct. 28 explosion that destroyed Orbital's Antares rocket and an unmanned spaceship carrying cargo to the International Space Station. Orbital is leading the investigation into the explosion under the oversight of the FAA, rather than a government agency since there were no fatalities, injuries or significant damage to the property of third parties, Nield said. Asked if the dispute over the cause of the accident pointed to the need for a government-led investigation, Nield said the FAA would look at that issue when it considered the report. He said Orbital was well-placed to lead the investigation since it designed, built and operated the rocket, and GenCorp had also provided input into the investigation. The Orbital-led accident investigation board included officials from NASA and the FAA, as well as a non-voting representative from GenCorp. "However this turns out, it is going to be very important to both companies and there may be some disagreement," Nield said. "We’ll certainly look at this carefully to make sure that all the potential causes have been properly examined and we don’t endanger the public in the future as we go forward." A senior Orbital executive on Tuesday said the blast was likely caused by excessive wear in the bearings of the Soviet-era NK-33 engine that was refurbished by GenCorp's Aerojet Rocketdyne unit. GenCorp said its own independent investigation showed that the excessive wear in the bearings was likely caused by so-called "foreign object debris" that got into the engine. The final determination of the cause could have significant financial implications for the companies involved. The Orbital said it expects to submit the final report of the company-led accident investigation to the FAA this week or next. NASA is completing its own investigation of the incident, but has no plans to make that assessment public. (Reporting by Andrea Shalal; Editing by Ken Wills)