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WRITTEN HISTORY FOR NEWS FROM CBS AND USED WITH AUTHORIZATION
NASA officials on Friday discussed the readiness of flights and authorized SpaceX to continue preparations for the development of a Falcon 9 shuttle and commercial Crew Dragon ferry for launch. , March 2, during an unmanned test flight to the International Space Station.
The long-awaited mission is a crucial step in NASA's $ 6.8 billion commercial crew program to end the agency's exclusive reliance on the spacecraft. Russian Soyuz for the transportation of US astronauts and astronauts to and from the station after the withdrawal of the space shuttle eight years ago. .
If all goes well, two NASA astronauts hope to take off aboard a Crew Dragon spacecraft during the first test flight piloted in July.
"It's more than a test flight, it's really a mission to the International Space Station, it's part of the program for commercial crews that really prepares us for the … flight of the crew that will be organized more late, "said Bill Gerstenmaier, director of spaceflight operations at NASA headquarters, said about the flightless test flight.
"This is an absolutely crucial first step as we move toward the eventual return of the team's launch capability to the United States."
Take-off from historic 39A platform is scheduled for 2 h 49 min 3 sec CET one week from Saturday, around the time the Earth's rotation causes the rocket into the plane of the station's orbit Space. This is the only way for today's rockets to make an appointment with an orbital target moving at almost five miles per second.
Emergency launch opportunities are available on March 5 and 9, but after that, NASA should stop after the Russian Soyuz flight scheduled for March 14 to transport cosmonaut Alexey Ovchinin, NASA flight engineers Nick Hague and Christina Koch. .
Ovchinin and Hague suffered a dramatic malfunction of the Soyuz booster during their first space flight last October, but the capsule and crew landed about 250 miles from the launch site in Kazakhstan. The Russian Space Agency has corrected the problem, revised the launch schedule and Koch, already in training for a downstream flight, has been added to the mission.
In any case, NASA officials participating in the FRR Friday at the Kennedy Space Center have reviewed the processing of the launch so far and the status of the remaining "open" points that need to be resolved or canceled before the flight and those which can be deferred in the short term.
Topics covered include the Crew Dragon parachute system and testing to certify its use in the upcoming pilot mission, temperature issues with capsule actuators and the status of fuel tanks. redesigned high-pressure helium, known as COPV, immersed in very cold liquid oxygen inside the Falcon 9 rocket.
Problems with an earlier version of the tank were blamed for a spectacular explosion on the Falcon 9 platform in 2016. The helium pressurization system was also involved in an in-flight breakup in 2015 when it was in the air. a leg holding a tank in place broke down, triggering destruction. from a Dragon freighter to the train station.
The problem for the Crew Dragon mission is to understand the physics that led to the explosion on the platform and to ensure that the redesigned tanks, called COPV version 2.0, are not vulnerable to the same mode of failure.
"One of the components of the overpack composite pressure vessel is fiber that is twisted together," said Gerstenmaier. "When they pressurize, they can rupture and potentially generate heat. If they can generate enough heat in the environment containing oxygen, they can be a source of ignition.
"So now we're going back and we're proving that this breakup is so unlikely that it will not be a concern."
One of the short-term problems to be solved concerns Russian concerns about the on-board computer and safety guidance systems aboard the Crew Dragon, which will control the final approach of the spacecraft to the space station.
According to Gerstenmaier, European, Japanese and Russian spacecraft that rendezvous with the station usually carry independent systems capable of stopping an approach in the event of a massive computer failure that could leave a ship in collision with the laboratory. . Crew Dragon relies instead on redundancy in the main computer system.
"One of the things I assigned was to take a closer look at some of the fault-finding functions and respond to various failures to make sure computers were doing the right thing, without the vehicle goes out or is dormant, then continues approaching and collides with the station, "said Gerstenmaier.
"This is the basic concern of the Russians. Why is there no separate system or enclosure to provide this backup capability? We think we have enough reasons for that.
Mr. Gerstenmaier stated that such technical problems were not unusual in the development of a human-rated spacecraft and as part of the Demo 1 mission: "We have not defined the Total envelope indicating where certain materials can work and how they can be used 'during the pilot phase. flights.
"But we know the equipment is good enough for this demonstration flight," he said. "In fact, we want him to fly to see if we're missing something else, and we expect to learn something about this fight."
Assuming that demo 1 takes off on March 2 as planned, Space Crew Dragon will hold a stand-alone rendezvous, joining the space station the day after launch and taking place at the lab's attack port, the same space shuttle. around 3 am on March 3rd.
The station's crew – Russian commander Oleg Kononenko, Canadian astronaut physicist David Saint-Jacques, and NASA flight mechanic Anne McClain – will open hatches and inspect the new spacecraft a few hours after mooring.
The flight plan calls for Demo 1 Crew Dragon to be disarmed on March 8th and to return to a splash in the Atlantic Ocean about 230 km east of Cape Canaveral. Nearby SpaceX recovery crews will fire the capsule on a ship and return it to Port Canaveral for detailed post-flight inspections.
Assuming no major problem develops – and assuming that a flight dropping test goes well this spring – astronauts Robert Behnken and Douglas Hurley hope to take off in a Crew Dragon this summer to launch the first launch of US astronauts aboard an American-made rocket since US ground since the end of the shuttle program in July 2011.
NASA is also funding the development of a Boeing capsule known as the CST-100 Starliner, which is expected to be launched unmanned at the top of a United Launch Alliance 5 Atlas rocket later in the spring. The first Starliner flight piloted by Boeing astronaut Christopher Ferguson and his teammates Nicole Mann and Mike Fincke is scheduled for the fall.
If these flights are going well, the operational US crew rotation flights could begin before the end of the year.
The last US Soyuz flight currently under contract is expected to be launched in July. Given the continuing potential for unexpected problems with commercial crew ships, NASA is exploring the possibility of acquiring two additional Soyuz seats, one to be used in the fall and the other next spring.
SpaceX currently holds contracts with NASA worth $ 3.04 billion for 20 space station replenishment flights and another contract for an unspecified amount for at least six additional flights up to $ 30 million. in 2024.
SpaceX also holds a $ 2.6 billion contract from NASA for the construction and launch of a pilot version of its Dragon cargo capsule. Boeing won a $ 4.2 billion contract to build the CST-100.
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