SpaceX says fix underway for rocket turbine wheel cracking

SpaceX's final version of the Falcon 9 rocket, which Elon Musk aims to launch before the end of the year, will fix a potential problem with cracks in its turbopumps, the company said on Thursday.

Its statement followed a report that the US Government Accountability Office will flag turbine wheel cracks in the rocket's turbopumps as a safety issue. NASA, the US space agency, and the Air Force are among SpaceX's customers.

The GAO’s preliminary findings were reported by the Wall Street Journal on Thursday.

In an email to Reuters, SpaceX said it has "qualified our engines to be robust to turbine wheel cracks. However, we are modifying the design to avoid them altogether,” said spokesman John Taylor.

In addition to flying cargo to the International Space Station, SpaceX has NASA contracts to begin flying astronauts to the orbiting research laboratory as early as 2018.

"SpaceX has established a plan in partnership with NASA to qualify engines for manned spaceflight," Taylor said.

GAO investigators found that the Falcon 9 turbopumps, which are part of the system that delivers propellants to the engine, have blades that are prone to cracking, the newspaper said.

SpaceX last month resumed flights following a 4-1/2-month investigation into why a rocket blew up as it was being fuelled for a routine pre-launch test in Florida.

The cause of the accident was traced to a burst canister of helium in the rocket’s second stage liquid oxygen tank. It was unrelated to the issue with the rocket’s turbopumps.

The accident was SpaceX's second since the Falcon 9 debuted in June 2010. The company's next launch is targeted for Feb. 14.