NASA and SpaceX officials have said little this week about the apparent explosion of a Crew Dragon capsule Saturday during a ground test at Cape Canaveral, and members of a safety advisory panel said Thursday they will be patient as investigators review high-speed imagery, telemetry data and wreckage to determine the cause of the accident.
A panel of safety advisors discussed the explosion during a previously-scheduled public meeting Thursday. Sandra Magnus, a former astronaut and member of NASA’s Aerospace Safety Advisory Panel, said it is too early to know how the accident will affect SpaceX’s crew capsule program.
The spacecraft involved in Saturday’s accident recently returned from a six-day test flight to the International Space Station. The unpiloted mission, designated Demo-1, was a pathfinder flight before NASA puts astronauts on the capsule on the next orbital launch, named Demo-2.
“Prior to the Demo-1 launch, NASA and SpaceX identified configuration changes and subsequent qualification work that would be required to be completed before Demo-2 was possible,” Magnus said. “Notwithstanding the recent incident, there is a large body of work yet to be completed between Demo-1 and a crewed flight. It’s still too early to speculate on how that body of work will alter based on recent events. As always, the panel encourages the team to be on guard against the dangers of schedule pressure.”
Before Saturday’s explosion, SpaceX appeared on track for the Demo-2 mission later this year, perhaps as early as September. NASA astronauts Bob Behnken and Doug Hurley are assigned to the Crew Dragon’s first piloted mission, which will pave the way for regular crew rotation flights to the space station, ending NASA’s sole reliance on Russian Soyuz ferry craft for the transportation of astronauts to and from low Earth orbit.
Engineers were preparing the Crew Dragon spacecraft, fresh from space after a splashdown March 8 in the Atlantic Ocean, for an atmospheric test flight as soon as July to validate the capsule’s ability to escape from a failing rocket in flight. A different capsule is under construction for the Demo-2 crew mission.
“The event occurred during a static fire test conducted prior to the in-flight abort test,” said Patricia Sanders, ASAP chair. “The firing was intended to demonstrate integrated system SuperDraco performance at two times vehicle level vibro-acoustic life for abort environments.”
The accident occurred as SpaceX tested the Crew Dragon’s SuperDraco abort engines, which are designed to quickly push the capsule away from its Falcon 9 launcher. The abort capability is a key safety feature for the crew capsule.
The crew capsule completed a test-firing of 12 smaller Draco maneuvering thrusters earlier in the day.
“Firing of 12 service section Dracos were successfully performed,” Sanders said. “Firing of eight SuperDracos resulted in an anomaly. The test site was fully cleared and all safety protocol was followed. The mishap did not result in any injuries.”
The Draco and SuperDraco thrusters burn the same combination of hydrazine and nitrogen tetroxide propellants, which ignite on contact. The toxic propellant was released into the air after Saturday’s explosion.
A photo taken by a Florida Today photographer from a local beach showed a reddish-orange cloud billowing over the Crew Dragon test site at Cape Canaveral. Such acidic clouds are typically associated with nitrogen tetroxide, the oxidizer used by the SuperDraco engines and a propellant commonly used on rockets and satellites.
SpaceX and NASA did not disclose any toxic vapor release in their statements after Saturday’s accident, but a dispatcher at the Brevard Country Emergency Operations Center reached by Spaceflight Now on Saturday evening said they were unaware of any threat to the public.
Fully loaded, the Crew Dragon carries about 1.5 tons of the caustic propellant mix, which pose health hazards to humans and animals.
Sanders said NASA and SpaceX immediately responded to the accident by executing mishap plans. SpaceX is leading the investigation with NASA participation and support, officials said.
“NASA has full insight into the results of the mishap investigation, which is reviewing all of the data collected during the test, including high speed imagery and detailed spacecraft telemetry data and will include analysis of the recovered hardware from the test,” said Josh Finch, a NASA spokesperson, in a written statement Thursday. “We have full confidence in the SpaceX and NASA team working the investigation to determine the cause of the mishap and design updates should they be required. ”
NASA managers overseeing the space station program are also following the progress of the investigation to assess whether the Crew Dragon accident has any implications for SpaceX’s cargo resupply missions, the next of which is scheduled for launch Tuesday from Cape Canaveral, according to Susan Helms, a former astronaut and ASAP committee member.
The cargo missions to the space station use a different version of the Dragon spacecraft without the SuperDraco abort engines, and officials have not suggested any delay to next week’s launch.
Discussing the Crew Dragon mishap inquiry, Sanders said “early efforts are focused on site-saving, data collection, and reduction and development of the anomaly timeline.”
“The investigation will take time before the root cause analysis is completed and will determine the impact to the Demo 2 and the in-flight abort test,” Sanders said.
SpaceX and NASA have not said if the accident occurred before the SuperDraco engine firing, as the thrusters ignited, or during their burn. SpaceX has also not confirmed if the vehicle exploded, as widely assumed, or the condition of the spacecraft and the test site after the accident.
The company acknowledged the accident Saturday evening, and SpaceX officials confirmed Sunday that it involved the Demo-1 capsule, the private space firm’s last public statement on the mishap.
The accident occurred at SpaceX’s Landing Zone 1, a site leased from the Air Force where the company lands Falcon 9 rockets returning to Earth after launching satellites. The company said Tuesday that the next Falcon 9 rocket landing will likely be moved from Landing Zone 1 to an offshore drone ship in the Atlantic Ocean.
Wayne Monteith, the Federal Aviation Administration’s associate administrator for commercial space transportation, told reporters Wednesday at the Kennedy Space Center that rigorous testing on the ground will eventually make the spacecraft safer to fly.
Monteith, a retired Air Force general who commanded the 45th Space Wing at Cape Canaveral until last December, called the Crew Dragon accident a “catastrophic event,” comparing it to an explosion of SpaceX’s Falcon 9 rocket on the launch pad in 2016 that destroyed the Israeli-owned Amos 6 communications satellite.
“We test equipment, we test systems, we want to do it before we put humans on-board, and quite frankly, you want to discover these types of problems now and not when you have lives at risk,” Monteith said. “So what you’ll find from this event was nobody was injured, you had a catastrophic event on the pad, much like when Amos 6 had an issue in 2016, not a single casualty, and that’s what we’re all about, public safety.”
The slow release of information since Saturday’s mishap has raised concerns among some observers about the transparency of SpaceX and NASA. The SuperDraco static fire was conducted by SpaceX, a privately-held company that also owns the Crew Dragon’s hardware and intellectual property, a new paradigm for a NASA-backed human spaceflight program.
An editorial published by the Orlando Sentinel on Wednesday called on more disclosures after Saturday’s accident.
“We don’t know the extent of the damage to the capsule or equipment involved in the test,” the Orlando Sentinel editorial board wrote. “We don’t know the range of possible causes SpaceX is investigating. We don’t know if SpaceX has another capsule ready to continue the program. We really don’t know what happened.
“There’s been no press conference. No opportunity to ask questions of company executives. No detailed news releases. No photos or video of the damage. The public is in the dark.”
The newspaper’s editorial board wrote that Musk’s companies have no obligation for public statements when spending private money.
“It’s not fine when the public is bankrolling his efforts, as it is with SpaceX’s crewed spaceflight program,” the editorial read.
NASA has awarded more than $3.1 billion in funding to SpaceX to develop the Crew Dragon spacecraft since the commercial crew initiative began in 2010. In a similar arrangement, the space agency has signed a series of commercial crew agreements and contracts with Boeing worth more than $4.8 billion over the same time period.
Boeing has also run into trouble during ground testing of abort engines on its CST-100 Starliner crew capsule.
The Starliner is scheduled for its first unpiloted demonstration flight to the space station in August, followed by a test flight with three astronauts on-board before the end of the year. The Starliner’s first missions were delayed to allow engineers to investigate and correct the cause of a fuel leak last year during a ground test-firing of the ship’s abort engines in New Mexico.
Boeing did not disclose the fuel leak, which held up the Starliner’s first flights by months, until weeks later, when the problem was first reported by Ars Technica.
The Aerospace Safety Advisory Panel was established by Congress in 1968 after the Apollo 1 fire killed three astronauts during a ground test. The panel’s charter is to provide advice and make recommendations to the NASA administrator on safety matters.
Magnus said the safety panel will be patient with the investigation, but the advisors said NASA managers in the Commercial Crew Program overseeing the Crew Dragon’s development — not SpaceX — have the final say on when astronaut flights can begin.
“We know that there’s a lot of interest regarding the recent SpaceX mishap,” Magnus said. “We are patient and allow the teams to investigate. But at the end of the day, the panel supports CCP’s continuing position that crewed missions will not happen until the program has received the data they require to ensure that we understand the margins, that we are controlling those margins and that we are operating in the environment that those margins require. And we will continue to emphasize that theme as the work goes forward in both programs.”
“Safety is a top priority for NASA and our commercial providers,” Finch said in a statement. “We will work with our partners to fly our crew members when their systems are ready. We don’t yet know what impact this will have to our target schedules. Additional information will be released as it is available.”
SpaceX intended to reuse the same Crew Dragon spacecraft that returned from the space station last month on the upcoming in-flight abort test. Teams will likely have to prepare a different vehicle for the abort test, a process that is all but certain to introduce delays in the Crew Dragon schedule, industry officials said.
The in-flight abort follows a pad abort test in 2015 that successfully proved the Crew Dragon’s SuperDraco engines, which each produce up to 16,000 pounds of thrust, could propel the capsule away from an emergency on the launch pad.
Before Saturday’s mishap, SpaceX and NASA engineers were continuing to examine unspecified issues with the Crew Dragon’s parachutes. There are also concerns with the chutes on Boeing’s Starliner capsule.
“Both providers still have work in front of them before crewed operations,” Magnus said. “The CCP program has specified to the contractors all the data that’s required to validate the safety of the design and the delivery of this information is what will determine when the crewed missions will commence, and not before.”
Magnus said NASA is “converging on a resolution” of concerns regarding high-pressure helium pressurant vessels contained within SpaceX’s Falcon 9 rocket. An earlier version of the composite over wrapped pressure vessel, or COPV, was blamed for the explosion of a Falcon 9 rocket on its launch pad in 2016, but SpaceX debuted a new helium tank design on a satellite launch last year.
While SpaceX and Boeing ready their spaceships for astronauts, NASA and Roscosmos — the Russian space agency — have agreed to extend the duration of several space station expeditions this year and next year to ensure U.S. astronauts remain on the orbiting complex.
NASA announced last week that astronaut Christina Koch, who launched to the space station from Kazakhstan on a Soyuz capsule March 14, will remain aboard the outpost until February 2020, months longer than originally planned. Koch will return to Earth on a different Soyuz spacecraft than she launched aboard, and her 11-month mission will be the longest single spaceflight by a woman.
NASA astronaut Andrew Morgan, set for liftoff on a Soyuz rocket July 20, will have his expedition in space extended by two months until early April 2020. Like Koch, Morgan will come back to Earth with a different crew than the one with which he launches.
The U.S. space agency also announced last week that Jessica Meir is assigned to a Soyuz crew set for launch Sept. 25. NASA said earlier this year it planned to purchase two more Soyuz seats for U.S. astronaut flights to mitigate further commercial crew delays — one late this year, apparently filled by Meir, and another in early 2020.
NASA has also approved an extended mission for the first Starliner test flight with astronauts. Boeing test pilot Chris Ferguson and NASA astronauts Mike Fincke and Nicole Mann originally planned to remain on the space station for several weeks, but the trio is now expected to live and work on the research outpost for several months as long-term residents.
Magnus said the measures to extend mission durations and buy more Soyuz seats give NASA and its commercial crew contractors some breathing room.
“In the meantime, NASA has appropriately established a contingency plan to ensure continued crew access to the ISS through late 2020 providing some temporal margin as they advance to crewed flight,” Magnus said.
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