Congressional investigators have sounded the alarm on turbine wheel cracks in the Falcon 9 rocket as well as other worrying aspects of SpaceX’s manned launches in the future.
According to Wall Street Journal, the U.S. Government Accountability Office’s preliminary findings show a pattern of issues with turbine blades pumping fuel into the rocket engines — the first to publicly identify a serious defect affecting SpaceX’s reusable rocket, especially with the final report’s release in the coming weeks.
Cracks In Manned-Mission Plans
The cracking-prone areas are deemed a major issue in the rocket’s safety, industry officials warned, saying it may entail redesign of the rocket’s turbopumps or the part of the system that delivers propellants to the engine. NASA has warned SpaceX of the said cracks’ unacceptable risk for manned missions, they added.
The issue surfaced as the Southern California-based company has delayed its first unmanned launch for at least two weeks, pending further testing of ground facilities. The planned blastoff has been rescheduled to no earlier than the middle of February.
SpaceX projects launching over double the eight rockets it blasted off in 2016, seeking to meet its NASA commitments and address a backlog of commercial missions. It envisions to eventually bring its total launch to about once a week past the decade’s end, including a couple of its Falcon heavy booster rockets — whose development has been years behind schedule, and maiden flight is poised for later this year — every year.
In a previous interview with WSJ, NASA acting administrator Robert Lightfoot said the cracks continued to emerge during tests as recent as September last year.
“We’re talking to [SpaceX] about turbo machinery,” Lightfoot said, adding they “know how to fix them” but expressed uncertainty on whether there will be a shift to bigger turbopumps.
The final government report will reportedly also focus on unrelated matters potentially threatening to delay manned launches by both SpaceX and its rival firm Boeing, with conclusions from external expert research. Investigators are said to have determined that both companies will likely miss a 2018 target to kickstart manned missions to the International Space Station.
Modifying Engine Design
In response to the GAO’s preliminary findings, SpaceX said it will fix the potential problem involving cracks.
“[We have] qualified our engines to be robust to turbine wheel cracks,” SpaceX said in a statement emailed to Reuters. “However, we are modifying the design to avoid them altogether.”
Last month, the Elon Musk-owned company resumed flights after a nearly five-month investigation into why its rocket exploded as it was being fueled for a routine pre-launch test — its second accident since the Falcon 9 rocket debuted in June 2010. The accident was linked to a burst helium canister in the second-stage liquid oxygen tank of the rocket, an issue unrelated to the turbopumps.
In late January, Musk announced that an upgraded Falcon 9 rocket version will be soon launched to deliver an EchoStar Corporation satellite to space. The upgraded version of the Falcon 9 rocket, also known as Block 5, would greatly enhance the performance and reusability of the rocket that is likely to be commissioned for flight by 2017’s end.
