After launching ten satellites into orbit last week and successfully landing a Falcon 9 first stage, Elon Musk’s SpaceX seemed on a roll. But things didn’t go so well when federal investigators had a look at the rockets. Reports from a Government Accountability Office (GAO) mention a dangerous defect that could compromise the safety of astronauts — namely, “persistent cracking of vital propulsion-system components.”

Image credits: NASA.

According to The Wall Street Journal (WSJ), the GAO is a federal agency that does audits on behalf of Congress and the remarks about the cracks in the rockets are part of a preliminary report. The information has not yet been officially confirmed.

“We do have work underway and it is due out later this month,” Charles Young, the managing director of GAO’s public affairs, told The Verge. “I can’t comment on the contents of the report until it is issued. It is still in draft form and we have not provided copies to any reporters.”

While the final report has not been published yet and it has not been released to the press, the WSJ gained access to a leaked version which raises troubling concerns. WSJ reports that the turbopump cracks could “pose an unacceptable risk for manned flights.”

This is not good news for SpaceX. The company’s appeal and potential are without a doubt exhilarating, yet the company’s evolution has had major ups and downs. Now, SpaceX is preparing for its most ambitious (and dangerous) project: manned spaceflight. They’re currently modifying the Dragon capsules to support transporting astronauts, and the earliest such mission is scheduled for 2018.

But things will be patched as soon as possible. SpaceX claims the rockets were built to withstand such cracks, and NASA’s acting director Robert Lightfoot says they’re working together with the company to fix the issues.

“We have qualified our engines to be robust to turbine wheel cracks,” John Taylor, a SpaceX representative, tells The Verge. “However, we are modifying the design to avoid them altogether. This will be part of the final design iteration on Falcon 9. SpaceX has established a plan in partnership with NASA to qualify engines for [crewed] spaceflight.”

Mr. Lightfoot said “we’re talking to [SpaceX] about turbo machinery,” adding that he thinks “we know how to fix them.” In the interview, Mr. Lightfoot said he didn’t know if the solution would require a potentially time-consuming switch to bigger turbopumps.

As the old saying goes, space is tough — and SpaceX is learning that first hand.