NASA will not publicly release the results of its own investigation into the catastrophic failure of a SpaceX Falcon 9 rocket that launched a Dragon resupply ship into the Atlantic Ocean in June 2015.
After saying it would release a summary of the agency’s investigation, NASA passed the buck to the FAA on an accident that destroyed $118 million worth of cargo the space agency was sending to the International Space Station (ISS).
“Since it was an FAA licensed flight, NASA is not required to complete a formal final report or public summary, and has deferred any additional products related to the matter at this time,” the agency’s Public Affairs Office (PAO) said in an email.
When Parabolic Arc checked with NASA last fall, the agency said officials were still working on a final report on the accident more than a year after it occurred. In December, PAO said it expected the report and a public summary to be ready in summer 2017.
Last week, the space agency reversed itself when Parabolic Arc checked on the agency’s progress.
Summer was the best information I had in December. I do not have an estimate for when a formal report or public summary will be finalized.
As you know, SpaceX CRS-7 was an FAA licensed flight and the FAA was responsible for overseeing the mishap investigation. NASA had full access to the data, was a part of the SpaceX investigation, and then conducted its own independent review of the incident. The Launch Services Program team briefed its results to NASA leadership in December 2015 (ahead of the Jason-3 mission in January 2016).
Since it was an FAA licensed flight, NASA is not required to complete a formal final report or public summary, and has deferred any additional products related to the matter at this time. The data is important for historical purposes, but the mishap involved a version of the Falcon 9 rocket, the version 1.1, that is now no longer in use.
NASA’s reasoning is curious given how the space agency responded to a similar accident that occurred eight months earlier.
Two Accidents, One Report
On Oct. 28, 2014, an Orbital Sciences Antares rocket lifted off from Wallops Island in Virgin carrying $51 million worth of NASA supplies aboard a Cygnus cargo ship bound for the space station.
Cygnus never got there. Antares had barely cleared the tower when the booster exploded in the most spectacular American launch failure of the 21st century. The cargo was lost and the launch pad suffered severe damaged.
The Cygnus launch was conducted under the same NASA Commercial Resupply Services (CRS) program as SpaceX’s Dragon flights. It was also a commercial launch licensed by the FAA.
Here’s another similarity: the explosion involved a version of the Antares rocket that would no longer be used. The explosion was traced to a failure of a turbo pump on an aging AJ26 first stage engine that was originally built for the Soviet Union’s lunar program more than 40 years earlier.
Within two months of the accident, Orbital announced it would replace the AJ26 engines with newly manufactured RD-181 engines. The change of engines required substantial modifications to Antares, which would not fly again for almost two years after the crash.
So, many of the factors NASA has cited for why it won’t release a public report on the Falcon 9 accident were also present for the Antares accident. Yet, the space agency still released a detailed executive summary of the mishap board’s findings one year after the accident.
NASA’s only public description of what its investigation found on the Falcon 9 accident is in an audit conducted by agency’s Office of Inspector General (IG).
The report focused primarily on the impact of the loss of Dragon on NASA’s resupply program and the agency’s response to the failure. The audit devoted exactly one page to the cause of the accident. It also raised more questions than it answered.
Two Accidents, Two Different Approaches
Despite suffering similar catastrophic failures in the ISS resupply program, NASA approached the investigations differently.
For the Antares failure, a contractor-led mishap board was formed composed of four Orbital employees, two NASA employees and one third-party expert. The investigation was done under the terms of the agency’s CRS contract with Orbital.
In the case of the Falcon 9 failure, two investigations were conducted. A mishap board was formed led by a SpaceX official that included 10 company employees and only a single FAA voting member. NASA officials served as non-voting observers along with representatives from the FAA, National Transportation Safety Board and the U.S. Air Force.
NASA’s Launch Services Program (LSP) conducted its own investigation. This was done because LSP had a contract with SpaceX for the future launch of Jason-3, an ocean-observation satellite that is a collaborative effort of NASA, NOAA and two European space agencies, CNES and Eumetsat.
“Before using a particular launch vehicle for a NASA mission, LSP certifies the vehicle for flight through insight and approval processes,” according to the IG audit. “The LSP investigation confirmed SpaceX’s implementation of corrective actions before approving the January 2016 Jason-3 launch.”
Although NASA had approved Antares to launch Cygnus supply ships to the space station, LSP had not certified the booster to carry other agency payloads into space. As a result, LSP was not tapped to lead an investigation into Orbital’s failure.
Two Investigations, Two Conclusions
The SpaceX-led mishap board concluded that an outside supplier was responsible for the accident that brought down the Falcon 9 booster.
The investigation found that the probable cause of the accident was a defective strut attached to one of the helium tanks inside the second stage liquid oxygen (LOX) tank. The strut broke in flight, causing a rupture in the helium system that over pressurized the LOX tank and caused it to burst.
Because the rocket crashed into the ocean, SpaceX was not able to recover any hardware to confirm the suspect strut was indeed defective. SpaceX said it made the determination after studying data from the accident. The company also found material defects in other struts it tested after the accident.
Only the 11 SpaceX employees on the mishap board signed the final accident report that was submitted to the FAA and NASA for review. The lone FAA vote representative did not sign the report for reasons that are unclear.
SpaceX CEO Elon Musk announced the company’s preliminary conclusion about the single defective strut about a month after the crash. However, there were immediate doubts about the conclusion. Several sources familiar with the accident told Parabolic Arc they believed the failure was actually more complex than SpaceX claimed.
The IG’s audit indicates that the LSP’s conclusions fell along those lines.
LSP did not identify a single probable cause for the launch failure, instead listing several “credible causes.” In addition to the material defects in the strut assembly SpaceX found during its testing, LSP pointed to manufacturing damage or improper installation of the assembly into the rocket as possible initiators of the failure. LSP also highlighted improper material selection and such practices as individuals standing on flight hardware during the assembly process, as possible contributing factors.
These three sentences are as detailed as the audit gets about NASA’s conclusions on what might have caused the failure. Still, there are some interesting nuggets in there.
For one, it makes clear that NASA doesn’t entirely buy the “defective strut snapped causing the rocket to explode, the supplier is to blame” conclusion reached by SpaceX.
The investigation acknowledged other struts in that same batch had material defects when SpaceX tested them after the accident. But, there are a number of other credible causes for the failure (manufacturing damage, improper installation and materials selection) that pointed to problems at SpaceX.
The space agency was concerned enough for NASA Administrator Charles Bolden and Associate Administrator for Human Spaceflight William Gerstenmaier to write a letter to SpaceX in February 2016 “expressing concerns about the company’s systems engineering and management practices, hardware installation and repair methods, and telemetry systems based on LSP’s review of the failure.”
The mention of the letter, which is a pretty big deal given what it said and who wrote it, is confined to a footnote in the IG audit. The letter did appear to have borne some fruit.
“SpaceX has taken action to correct the deficiencies that led to the failed strut assembly and to address NASA’s concerns by conducting inspections, replacing suspect parts, and conducting additional testing. The company also reviewed the certifications of all spaceflight hardware and altered its quality control processes to better align with NASA technical standards,” the audit stated.
The IG’s audit leaves a number of questions unanswered that a detailed public summary of the LSP’s investigation would be able to address.
What type of manufacturing damage might have occurred? What improper materials might SpaceX have been selected? And what issues did NASA found with the telemetry system?
Here’s another issue: we know from SpaceX’s own public statements that the year before the accident, the company was having trouble with helium leaks in the Falcon 9. The problems corresponded to a switch from tanks provided by an outside vendor to ones produced in house at SpaceX.
The leaks were merely a major nuisance in 2014, limiting SpaceX to six launches instead of the 11 or 12 it planned to conduct. But, what if the leaks were merely a prelude to the loss of the Falcon 9 in June 2015 for reasons other than a lone defective strut?
The IG report also noted issues with the process used to get Falcon 9 back into the sky. On Dec. 18, 2015, the FAA Office of Commercial Space Transportation (FAA AST) issued a launch license for Falcon 9 to return to flight after reviewing SpaceX’s mishap report.
“Although FAA officials had access to LSP meetings during the SPX-7 investigation, the FAA did not receive LSP’s final report with findings and recommendations for corrective actions before SpaceX obtained FAA approval to return to flight in December 2015,” the IG audit stated.
“While the FAA was not required to review LSP’s findings before issuing a license, this uncoordinated approach increased the risk the FAA approved a launch without fully understanding the LSP investigation’s findings and recommended corrective actions,” the audit added.
The same day FAA approved SpaceX’s launch license, LSP officials briefed NASA’s top management on the results of its investigation and the company’s actions to address the cause.
Three days after the FAA issued its launch license and LSP officials gave their briefing, the Falcon 9 made a spectacular return to flight by launching a satellite and landing the first stage back at Cape Canaveral. This was the first flight of the upgraded Falcon 9 v.1.2.
The following month, NASA’s faith in SpaceX was rewarded with the successful launch of Jason-3 on the last Falcon 9 v1.1 booster. Seven more successful flights followed with the upgraded version of the launch vehicle.
Then came Sept. 1. A Falcon 9 exploded on the launch pad while being fueled for a pre-flight engine test, destroying Spacecom’s Amos 6 communications satellite. The failure once again originated in the the second stage as it did with the Falcon 9 that occurred 14 months earlier.
SpaceX ruled out any problem with the revamped strut assembly. Instead, it said that super-cold liquid oxygen from the LOX tank had built up in buckles in a helium tank’s outer carbon-composite liner. The LOX turned solid, resulting in friction that caused the helium tank to explode.
The on-pad explosion raises some additional questions. In identifying and correcting the problem with the strut, did SpaceX actually address the underlying root cause of the June 2015 failure? Are there any common links between the helium leaks in 2014, the in-flight failure and the launch pad explosion? Or are they simply separate, unrelated problems with a troubled upper stage?
A Lack of Transparency
The IG audit faults NASA for the ways in which the agency has responded to the two failures in the Commercial Resupply Services program. The space agency lacks a standardized procedure for mishap investigations, did not find elements of a full “root cause” determination, and allowed both SpaceX and Orbital to conduct their own investigations without screening board members for conflicts of interest, the audit found.
“We acknowledge SpaceX’s investigation was transparent and the observers from FAA, ISS, LSP, NTSB, and USAF had access to the investigation’s data and analysis. However, an investigation led by the employee responsible for the SPX-7 launch and run by the contractor responsible for the failure raises questions about inherent conflicts of interest,” the report stated.
“While NASA, Orbital, and SpaceX, have similar incentives to safely and quickly return to flight, the structure of the contractor-led investigations may not result in a full review of all programmatic and organizational contributing factors and consequently these factors may not be fully addressed to prevent future failures,” the report added. [Emphasis mine]
Another issue is NASA’s inconsistency in the release of information about these two failures. The space agency published a detailed summary of the Antares failure. But, the technical explanation of NASA’s findings about the Falcon 9 failure has been reduced to three sentences in an IG audit.
That doesn’t seem right. The public is paying billions of dollars to these companies to haul supplies up to the space station. When one of them failures, it has a right to know what happened regardless of which company it is that had the bad day.