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A prototype of the SpaceX Crew Dragon during a previous test of SuperDraco thrusters of the vehicle, involved in the incident at Cape Canaveral on April 20 (credit: SpaceX) |
by Jeff Foust
Monday, April 29, 2019
At first, we did not really know what caused the dark cloud spotted this Saturday afternoon sunny on the Space Coast of Florida, but it could not have been good.
During the afternoon, surfers and other beachgoers, as well as a press photographer, saw a dark, reddish cloud rising from somewhere in the vicinity of the base. Cape Canaveral. In the absence of launching or other test activities announced in advance, what was causing it was initially a mystery.
BREAKING: #SpaceX According to the 45th Space Wing, Crew Dragon suffered an anomaly during the tests. You could see smoke on the beaches.
"On April 20, an anomaly occurred at Cape Canaveral AFS during the Dragon 2 static test fire. The anomaly was controlled and no injuries occurred." pic.twitter.com/If5rdeGRXO
– Emre Kelly (@EmreKelly) April 20, 2019
By the end of the day, Base and SpaceX officials had announced what had happened: the company was testing its Crew Dragon vehicle at Landing Zone 1 (the former Launch Complex 13 at Cape Canaveral) when something was wrong.
| "We will learn, make the necessary adjustments and move forward safely with our commercial crew program," said Bridenstine. |
"Earlier in the day, SpaceX performed a series of engine tests on a Crew Dragon test vehicle on our test bench located in Landing Zone 1 in Cape Canaveral, Florida. The first tests were done successfully, but the final test resulted in an anomaly on the test bench, "said a spokesman for the company in a statement sent via email. "Our main goal is to ensure that our systems meet stringent safety standards and to detect such anomalies prior to flight. Our teams study and work closely with our NASA partners. "
More than a week later, that is what SpaceX has leaked about the incident, the anomaly or the accident. The company did not provide additional updates on the event, or even on the status of the ongoing investigation. This has become a source of frustration for some who think society should be more open as a NASA-funded program.
"NASA should not allow this secret unless a program involves military secrets, which it does not," argued Orlando Sentinel in an editorial last Wednesday. The agency, she said, should demand that SpaceX and the other commercial crew, Boeing, "be more transparent and open."
NASA does not seem to be pressuring SpaceX to provide more information. NASA's director, Jim Bridenstine, said in a statement a few hours after the incident that NASA and SpaceX were working on the assessment of the incident. "We will learn, make the necessary adjustments and move forward safely with our commercial crew program," he said.
His statement confirmed a key aspect of the incident: it took place during a test of the SuperDraco thrusters of the spacecraft, designed to move the spacecraft away from its Falcon 9 launcher in case of emergency. (The thrusters have also been considered to allow propellant landings of the spacecraft on land, which SpaceX has since postponed indefinitely in favor of splashing.) The propellers use the propellant-based hypergolic combination. hydrazine and nitrogen tetroxide; the reddish color of the cloud appeared indicative of nitrogen tetroxide.
The incident was also discussed last Thursday at a meeting of the NASA Safety Advisory Committee, the Advisory Committee on Aerospace Safety (ASA), but these gave only few details about the incident. The test took place after tests of the Space Shuttle's smaller Draco thrusters were successfully completed, said ASAP President Patricia Sanders. "The firing of eight SuperDracos resulted in an anomaly," she said, without specifying the details of this test or the resulting anomaly.
SpaceX is conducting the investigation since the anomaly, she said, with the participation of NASA, while they were working on securing the test site and collecting data. She and other members of the group called for patience, giving investigators time to study what happened. "We know that the recent SpaceX disaster is attracting a lot of attention. We are patient and allow teams to investigate, "said Sandra Magnus, ASAP member and former astronaut.
Although the details of the accident remain rare, its implications are a little clearer. The Crew Dragon capsule involved in the incident was the same one that had flown the unarmed Demo-1 test flight in March. The scale of the damage she suffered was not reported, but was probably heavily damaged or even destroyed.
The capsule was to fly again as early as June during an in-flight abandonment test, where she would have fired with her SuperDraco thrusters to get away from a Falcon 9 after take-off. This long delayed test was an important step not from his current commercial crew development contract, but from an earlier agreement funded under the Space Law.
If this capsule actually requires major repairs or is irreparably damaged, it would delay this flight abandonment test, perhaps for a prolonged period. This could, in turn, delay the crew flight of Demo-2 to the space station involving two NASA astronauts.
| "Despite the recent incident, there is still a lot of work to be done between Demo-1 and a crewed flight," said Magnus. |
ASAP, at its meeting last week, refused to speculate on the impact of the anomaly on the calendars. "The investigation will take time before the root cause analysis is complete and will determine the impact on Demo-2 and the flight abandonment test," Sanders said.
While Demo-2 was officially scheduled for July, this flight would probably have occurred later in the year, even before the SuperDraco anomaly. Magnus noted that SpaceX has taken a "spiraling" approach to development, gradually adding capabilities. This meant that the company still had some work to do, despite the successful flight of Demo-1 in March, before launching Demo-2 (see "The Beginning of the End of Commercial Crew Development", The Space Review , March 11, 2019.)
"Before the launch of Demo-1, because of this spiral development approach adopted by the company, NASA and SpaceX have identified configuration changes and subsequent qualification work that should be completed before Demo-2 is completed. possible, "she said, echoing the comments. NASA officials at the time of the Demo-1 mission.
"Despite the recent incident, there is still a lot of work to be done between Demo-1 and a crewed flight," she said, adding that it was too early to speculate on the consequences of the SuperDraco anomaly.
SpaceX is not the only company to have problems with its launch abandonment system. Last summer, Boeing encountered a problem with the abandonment system of his CST-100 Starliner vehicle. Several engine values failed when ordering, the company said at the time.
It seemed like a pretty minor problem – at least compared to what SpaceX had experienced – but it still caused significant delays for the problem. In a statement dated April 3, NASA said the company was just beginning to prepare to revive its hot testing campaign of service modules at the White Sands test facility of the NASA in New Mexico, now that the problem of the valves had been corrected. "The new equipment, including the launch engine shutoff valves, has been redesigned and manufactured and is being installed on the test engines," said L & # 39; agency.
This statement came as NASA announced new dates for Boeing's two commercial flight crews: an unprepared test is now scheduled to be launched in August, followed by a crew test no earlier than November. Boeing was aiming for the month of May for the unprepared test, but said that range issues – another Atlas 5, equipped with a military communications satellite, planned for late June – meant they Had virtually no chance of getting started in May before having to return to the platform. for this June mission.
This shorter gap between unmanned and crewed test flights for Boeing – just three months – is achievable, suggested Magnus. "Boeing opted for a more traditional path, investing more effort before integrated testing to establish a more mature design from the start," she said, compared to SpaceX's spiral approach. She added, however, that the company still faced "the submission and analysis of the data required for the final certification and audit processes."
These events, combined, clearly show that it is highly unlikely that either company will be certified to transport NASA astronauts by the end of the year. This was a problem for NASA, as the organization's access to the Soyuz seats was to be completed by early 2020.
However, NASA has taken several steps in recent months to address this potential loss of access. In particular, it announced in February that it intended to buy two Soyuz seats in Roscosmos, which would guarantee access to the station until autumn 2020.
| NASA added that extending the stays of two ISS astronauts "also allows NASA to devote as much time as possible to other research aboard the station, while launchers' suppliers American commercial crews prepare for operations to and from US ground and space station ". |
In addition, NASA announced on April 17 that two ISS astronauts would remain on the station longer than the normal six-month rotation of the crew. Christina Koch, arriving on the station in March, will remain until next February, a 328-day stay that will set the record for a woman's longest space flight. Andrew Morgan, who is scheduled to enter the station in July, will remain on this station until next spring, stay of 255 days.
NASA said extended stays would allow scientists to collect more data on the effects of long-duration spaceflight, such as Scott Kelly's 340-day stay. But, adds the agency in the announcement, the extension "also allows NASA to devote as much time as possible to further research aboard the station, while US suppliers of commercial flight launchers prepare for operations to and from US soil and the space station. "
The third measure to maintain access is to exercise an option that has been studied for a year: to transform the Boeing Starliner crew flight into an extended test flight at the station, which NASA announced at the beginning of April by announcing the new schedule of test flights. NASA astronauts Nicole Mann and Mike Fincke, along with his former astronaut and current Boeing employee Chris Ferguson, will potentially spend several months on the station under the new plan. NASA stated that the exact duration of this mission would be determined later.
ASAP commended NASA for these measures, which should help reduce the time constraints placed on commercial flight crew suppliers. "NASA has correctly established an emergency plan to ensure US access to the crew until the end of 2020, with a margin of time as it moves forward. they are moving towards crewed flights, "said Magnus.
Thus, while the urgency of flying commercial vehicles is somewhat blurred, it remains to be seen what happened to the Crew Dragon vehicle there is more to A week. But just as the black cloud of the anomaly flew towards the sea and has dissipated, so does the uncertainty that has obscured what has happened. spent this afternoon on the spacecraft and its implications for the entire commercial crew program. Finally.
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