NASA clears next SpaceX crew mission to launch, pending toilet system review – Spaceflight Now
NASA officials from the Kennedy Space Center gave the green light Monday to continue preparations for the Halloween launch of four astronauts to the International Space Station, pending further analysis of a modification to the toilet system on the capsule. owned by SpaceX.
âOn the commercial crew program, we have a bit of work to do with SpaceX before the flight,â Steve Stich, NASA’s commercial crew program manager, said at a press briefing Monday night.
NASA engineers want more time to analyze SpaceX information on a change to the Crew Dragon spacecraft’s toilet system after encountering an issue with the unit on the Dragon Crew’s last flight, the all-civilian mission Inspiration 4.
Bill Gerstenmaier, SpaceX vice president of construction and flight reliability, said he believes the two unresolved technical issues have a “good path to shutdown” in time for the launch of the next Crew Dragon flight. to the space station, known as Crew-3, set for 2:21 a.m. EDT (0621 GMT) Sunday.
The mission is SpaceX’s third operational crew rotational flight to the NASA contracted station, and the fifth total astronaut flight using a Crew Dragon capsule. Commander Raja Chari, Pilot Tom Marshburn, Mission Specialist Kayla Barron and European Space Agency Astronaut Matthias Maurer will travel to the Kennedy Space Center from their base in Houston on Tuesday for final pre-launch preparations.
Assuming a launch on time on Sunday, Chari and his teammates will drive their SpaceX transport ship to an automated docking with the space station at 12:10 a.m. EDT (0410 GMT) on Monday, November 1. They will stay at the station until April. , when the next SpaceX crew rotational fight is scheduled for launch.
One of the technical issues still under discussion concerns the final NASA approval of SpaceX’s change to the toilet system on the spacecraft for the Crew-3 mission set to launch this weekend. The other is the toilet of the Crew Dragon capsule currently docked at the space station, which is supposed to return to Earth on November 4 or 5 with four astronauts completing a six-month expedition in orbit.
NASA and SpaceX officials met on Monday for a Flight Readiness Review to discuss the status of the upcoming Crew Dragon spacecraft, a brand new capsule named Crew Dragon Endurance, as well as its Falcon 9 launcher, systems on the ground, the space station and the formation of the four astronauts who will mount the spacecraft into orbit.
Officials also reviewed the readiness of the Crew Dragon Endeavor spacecraft for the Crew-2 mission which is due to return to Earth next week.
“All parties were ‘gone’ today, with of course the understanding that we need to complete these two open areas for testing and evaluation,” said Kathy Lueders, NASA associate administrator for space operations. âThe flight readiness exam is one step in a final series of major steps to prepare for the flight. “
Preparations for the launch of Crew-3 continued in Florida on Monday. Over the weekend, SpaceX moved the fully powered Crew Dragon Endurance spacecraft from a processing facility at the Cape Canaveral space station to the Falcon 9 rocket integration hangar at Kennedy Space Center.
SpaceX plans to roll the integrated Falcon 9 rocket and Crew Dragon Endurance spacecraft to pad 39A on Tuesday evening. A firing test of the recycled booster from the first stage of Falcon 9 is scheduled for Wednesday evening.
Engineers will present new data on the toilet system and other mission elements to management during a launch readiness review on Friday.
Inspiration4 flight was launched on September 15 from the Kennedy Space Center and returned to a safe landing in the Atlantic Ocean three days later. It was the first fully commercial crewed trip to orbit without any major involvement from a government entity.
The only problem with the three-day mission was a malfunction in the toilet system on SpaceX’s Crew Dragon Resilience spacecraft. SpaceX vice president of construction and flight reliability Bill Gerstenmaier said a tube inside the spacecraft’s urine storage system became disconnected during the Inspiration4 mission.
“There is a storage tank where urine is going to be stored in the vehicle, and inside that storage tank there is a tube that is not connected or has come off, and it allowed urine, essentially, not to enter the storage tank but, essentially, to enter the ventilation system, âsaid Gerstenmaier.
He said the issue did not cause any major issues on the Inspiration4 mission.
âWhen we retrieved the vehicle, we looked under the ground and saw that there was contamination under the ground from Inspiration4,â said Gerstenmaier. “We then thought that there might be a similar type of problem with the crew vehicle in orbit, Crew-2. So we went ahead and looked at the vehicle on Crew-2, and yes, there was an indication of some contamination under the ground. “
The astronauts used an endoscope to inspect the Crew Dragon Endeavor waste management system at the space station. Ground crews want to make sure there are no safety concerns with Crew-2’s astronauts returning to Earth next week, and officials have previously said they will tell the crew to Limit their use of the Dragon Toilets during their stay in the spaceship from undocking to landing.
âFor Crew-3, we solved this problem in the tank by essentially making it a fully welded structure with no more joints that can peel off and disconnect,â said Gerstenmaier, a long-time and highly respected engineer and manager at the NASA before joining SpaceX.
SpaceX provided data on the design change to engineers at NASA, who are still evaluating the change.
For the Crew Dragon capsule already in space, engineers at NASA and SpaceX are evaluating how the urine leak could degrade due to corrosion over time. SpaceX uses a material called Oxone to remove ammonia from urine.
“We did extensive testing where we took aluminum samples, and we placed an Oxone-urine mixture on it, and then we placed them in a chamber that mimics the humidity and temperature conditions on board the ship. space station, and we looked at the growth of corrosion over a long period of time, “Gerstenmaier said.” And we see that this corrosion growth is confined to the low humidity environment on board the station and then the corrosion level is included on the Crew-2 capsule. “
The space station’s Crew Dragon Endeavor spacecraft toilet was also used less than the garbage disposal system during the three-day Inspiration4 mission. The crew-2 astronauts only used the Dragon system during their day-long trip to the space station.
âThere was a little more contamination on Inspiration4 than on Crew-2, so we understand that basically inspiration4 is borderline, in a sense, for us to move forward,â said Gerstenmaier. âWe performed all the analyzes, we performed the physical tests, we performed sample tests on the aluminum and, fortunately, we deliberately chose an aluminum alloy that is very insensitive to corrosion. pretty good overall shape.
“We’re going to check things out, we’re going to check out some things,” Gerstenmaier said. “We still have a few samples that we will remove from the chambers and inspect, but we will be ready to go and make sure the crew is back safely.”
Engineers looked at similar seals throughout the Crew Dragon spacecraft to make sure that no other components were at risk of peeling off in flight, according to Gerstenmaier.
âWe challenge ourselvesâ¦ don’t just focus on the immediate problem or just fix it,â he said. “But look beyond this problem, and how could there be an underlying underlying cause, or a fundamental problem, that has broader implications that can help us all to fly safely.”
SpaceX also added stitching to the Crew Dragon Endurance spacecraft’s brake parachutes after engineers discovered a “small element of abrasion” on the chutes used in the Inspiration4 mission.
âWe saw what happened, we inspected it after the flight. We learned that there are seams that could be improved, âsaid Stich. “We got on the vehicle on Crew-3, the tech came in and sewn that up and put some protection in there, and NASA looked at that.”
Some might call the extra scrutiny paranoia, but Gerstenmaier said on Monday he preferred to use the term “stay hungry.”
âWhat we’re looking for are tiny clues or tiny, tiny imperfections that someone might look at a plot and wonder why this temperature has risen here, or this pressure has changed here,â Stich said. âSo you’re really trying to dig into all of these kinds of things and try to figure it out, and then make it better and fly safe.
âThis is the culture that SpaceX has, I think, in terms of the culture of learning, the culture of engineering, or the culture of testing that NASA has also had in the past, and we are embracing that. Same thing on our side. We have engineers who dig into the issues, look at the system, and make sure we can continue to fly safely. “
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