The cause of the accident was traced to a burst canister of helium in the rocket’s second stage liquid oxygen tank.In an email to Reuters, SpaceX said it has "qualified our engines to be robust to turbine wheel cracks.The accident was SpaceXs second since the Falcon 9 debuted in June 2010.. The companys next launch is targeted for Feb.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.The GAO’s preliminary findings were reported by the Wall Street Journal on Thursday. However, we are modifying the design to avoid them altogether," said spokesman John Taylor.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."SpaceX has established a plan in partnership with NASA to qualify engines for manned spaceflight," Taylor said. NASA, the US space agency, and the Air Force are among SpaceXs customers.Its statement followed a report that the US Government Accountability Office will flag turbine wheel cracks in the rockets turbopumps as a safety issue.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. 14. It was unrelated to the issue with the rocket’s turbopumps.SpaceXs final version of the Falcon 9 rocket, which Elon Musk aims China Wholesale Post Cap Suppliers to launch before the end of the year, will fix a potential problem with cracks in its turbopumps, the company said on Thursday