Endeavour moved to 39A as astronauts arrive and Crew-2 mission is cleared for launch
Shane Kimbrough, Megan McArthur, Thomas Pesquet, and Akihiko Hoshide have arrived at the Kennedy Space… The post Endeavour moved to 39A as astronauts arrive and Crew-2 mission is cleared for launch appeared first on NASASpaceFlight.com.
Shane Kimbrough, Megan McArthur, Thomas Pesquet, and Akihiko Hoshide have arrived at the Kennedy Space Center in Florida for their upcoming launch to the International Space Station on the same day their spaceship, the Crew Dragon Endeavour, was moved to its sea-side launch pad.
NASA and SpaceX are currently targeting launch of the Crew-2 mission on Thursday, April 22 at 06:11 EDT / 10:11 UTC from LC-39A ahead of docking 23 hours later on Friday, April 23rd.
Ticking off important milestones for NASA and SpaceX for the Commercial Crew Program, Crew-2 is SpaceX’s second long-duration mission to the International Space Station (ISS). It is the first crewed mission using a previously flown Crew Dragon spacecraft and Falcon 9 first stage.
Named Endeavour, the Crew Dragon capsule was previously flown for the Demo-2 mission, which was the first crewed flight for SpaceX and carried Bob Behnken and Doug Hurley to the Station.
Crew-2 will also be the second flight of the Falcon 9 booster B1061, which previously launched Crew Dragon Resilience and the Crew-1 mission in November 2020 carrying NASA astronauts Victor Glover, Mike Hopkins, Shannon Walker, and Japan Aerospace Exploration Agency (JAXA) astronaut Soichi Noguchi.
Crew-2 will also be the first time a European will fly on a US commercial vehicle and capsule; likewise, with liftoff, Megan McArthur will become only the forth woman to pilot a US human space mission after Eileen Collins, Susan Still, and Pamela Melroy from the Shuttle era.
#ICYMI @NASA's @SpaceX Crew-2 astronauts arrived at @NASAKennedy earlier this afternoon to start final preparations for launch!
They are scheduled to lift off on April 22 for a six-month science mission to the @Space_Station: https://t.co/VfSHJF6HPu pic.twitter.com/TRvkt563Tr
— NASA Commercial Crew (@Commercial_Crew) April 16, 2021
Once Endeavour reaches the ISS again, it will mark the second time two JAXA astronauts will work together on the ISS. The previous occurrence was in April 2010 when Naoko Yamazaki arrived at the Station as a part of STS-131 while Soichi Noguchi was serving a long duration increment on the outpost.
In a marked difference from the entire history of the US human space program (save an overlap in Gemini), Crew-2 will mark the second time — and first time since December 1965 — that two US human space missions are in orbit at the same time.Crew-2 UPDATES
As part of final preparations for the launch, the crew departed from Ellington Field near the Johnson Space Center in Houston and flew to Kennedy aboard a charter plane Friday. Upon arrival, they were greeted by NASA’s Acting Administrator Steve Jurczyk, Kennedy Space Center Director Bob Cabana, Manager of ISS operations for ESA Frank de Winne, and Manager for ISS operations for JAXA Junichi Sakai.
“How great is it to have the Crew-2 crew here for the third launch of humans to space in less than a year. I mean, what an exciting time for the nation’s human space program,” noted Cabana. Jurczyk added, “I’ve been with NASA 32 years, and it’s been an amazing career and it never ceases to amaze me the talent and bravery of our astronauts and our foreign-partner astronauts. Thank you guys for what you do for NASA and the nation and the world.”
Astronaut Shane Kimbrough, commander of the Crew-2 mission said, “It is awesome being at Kennedy space center, especially in the launch week. It’s definitely getting real and our crew is extremely well trained from NASA, SpaceX, and international teams.”
Thomas Pesquet added, “Everyday there is a major milestone, bringing us closer to flight and it makes it more real. The NASA and SpaceX team makes it seem routine, but it’s not; we know it’s not, and we know there’s a lot of work that goes into it and we’d like to thank all those people involved.”
To that hard work, prior to the crew’s arrival, NASA and SpaceX teams, joined by ESA and JAXA representatives, conducted the Flight Readiness Review (FRR) for the Crew-2 mission on Thursday, April 15. This was the first of two reviews to evaluate the overall readiness of all the teams and flight hardware and software and discuss any pending issues.
“It was a very moving day,” said Kathy Lueders, Associate Administrator, Human Exploration and Operations Mission Directorate at NASA. “Here we are 11 months [after Demo-2] getting ready for the third crewed flight. Looking back, it’s really, really amazing what both the NASA and SpaceX teams have accomplished.”
The FRR proceeded smoothly — thanks in large part to the exceptional performance of Crew Dragon during Crew-1 — with no major issues identified and only one open item to investigate and discuss at the L-2 day Launch Readiness Review.
The open item, for which an exception was asked for and granted unanimously, relates to liquid oxygen load practices of the Falcon 9 first stage.
William Gerstenmaier, Vice President of Build and Flight Reliability, SpaceX, noted that teams at SpaceX’s test facility in McGregor, Texas, discovered something unexpected with the propellant loading configuration for Falcon 9’s first stage.
During a test in Texas, when weather forced them to stop and change configurations, teams noted about three to four inches of additional liquid oxygen in the tank than they predicted they should have. To learn more about this issue, teams physically measured the amount of liquid oxygen loaded into the stage under normal operations and found there was a difference from the predictions, verifying the previous observation.
Importantly, no one believes this is an issue or safety concern as all SpaceX Falcon 9 rockets have flown in this configuration; however, as Gerstenmaier related, “We really pay attention to these really small things. I think in a normal program this amount of difference wouldn’t have mattered to anyone.”
“But in our world, we kinda take the extra step to go review it, look at the consequences, what happens (in the) worst case, what if it’s an indicator of something even more serious? We have those discussions; we’ll share all that data with NASA and make sure we are really ready to go do what we need to go do for the static fire coming up.”
The static fire is currently scheduled for Saturday, April 17 at 06:11 EDT / 10:11 UTC. Falcon 9 and Crew Dragon Endeavour were moved to the pad on Friday morning for launch — marking the first time in 10 years, since July 8, 2011, that a previously-flown human spacecraft took its place on LC-39A.
Separately, during the Crew-2 FRR press conference, Steve Stich, Commercial Crew Program Manager, NASA, gave insight into the review process for the Dragon and Falcon 9 flight proven hardware being used for the first time on a crewed mission.
“We had to do an extensive amount of work to certify Dragon for reuse and also the Falcon 9. We reviewed over 3,000 products that SpaceX provided us on that vehicle. We had to look at how the structure would perform in the second flight. We went back and looked [to make sure] all the requirements were met, and we made sure that all the hazards for Falcon 9 and Dragon were controlled.”
Stitch also touched on upgrades made to the propulsion systems in the Dragon spacecraft to eliminate titanium valves from certain locations and replace them with stainless steel and inconel in further response to the anomaly that SpaceX’s Crew Dragon suffered on April 20, 2019, when the spacecraft — which returned to Earth after the successful, uncrewed Demo-1 mission — exploded during a static fire test of its SuperDraco abort engines.
The cause of the mishap was due to a leaky component which allowed dinitrogen tetroxide to leak out and react violently with the titanium components under very high pressure.
Other propulsion upgrades to Endeavour include better fuel flow rates to the SuperDraco abort engines to help increased the maximum wind limits for such an operation.
Endeavour’s heat shield was also upgraded after NASA and SpaceX discovered more than expected wear at certain heat shield locations after the spacecraft returned to Earth in August 2020. This upgraded heat shield was tested during the CRS-21 mission — utilizing the upgraded Cargo Dragon spacecraft — and was certified for flight on Crew-2.
Additional upgrades were made to the battery systems and regular Draco orbital maneuvering thrusters.
As for the Falcon 9 booster, no engines were changed from the previous flight, but two turbopumps — which supply liquid oxygen and RP-1 kerosene to the main combustion chamber of the engine — were replaced along with one of the landing legs that was damaged due to a hard landing during the Crew-1 mission.
“It took about 10 months of intensive review. Super proud of everybody in the NASA and SpaceX teams who went through that review and worked long hours, sometimes nights and weekends to do that work. But we got through it and are in a good posture for the reuse today.”
Now at Kennedy, the crew will continue “flight crew health stabilization” — or quarantine, a routine part of final preparations for all missions to space.
Crews currently quarantine for two weeks before liftoff, both at their homes or in facilities at Johnson Space Center and Kennedy Space Center. While the two week quarantine was in place long before the current COVID-19 pandemic, additional procedures like mask wearing, physical distancing, and other safeguards have been added due to the pandemic.
The astronauts will also be tested twice for COVID as a final precaution before liftoff.
(Lead image: Crew Dragon Endeavour rolls out to LC-39A for launch on the Crew-2 mission.)
The post Endeavour moved to 39A as astronauts arrive and Crew-2 mission is cleared for launch appeared first on NASASpaceFlight.com.