NASA and SpaceX managers in Florida decided early Saturday to delay the launch of the next crew to the International Space Station from Sunday to Wednesday, when high winds and rough seas are expected to subside along the Falcon 9 rocket’s flight path across the Atlantic Ocean.
Officials tracked weather and sea conditions in downrange abort zones throughout the week in hopes the forecast would improve enough to fall within safety criteria. SpaceX’s Crew Dragon spacecraft could splash down along the flight path northeast from the launch site at NASA’s Kennedy Space Center if the capsule needs to escape its Falcon 9 rocket in an emergency.
The weather forecast for the launch site at Kennedy was nearly perfect, with a 90% chance of acceptable conditions for liftoff of the Falcon 9 rocket and Crew Dragon spacecraft at 2:21 a.m. EDT (0621 GMT) Sunday.
But the abort zone conditions were another story, with winds and waves exceeding limits for a safe splashdown of the Crew Dragon spacecraft. NASA and SpaceX managers were particularly focused on a part of the Atlantic Ocean off the coast of the Carolinas and the Mid-Atlantic states, where the Crew Dragon might splash down in the event of a rocket failure during staging a few minutes after liftoff.
The offshore conditions are forecast to improve in time for the backup launch opportunity Wednesday at 1:10 a.m. EDT (0510 GMT). The weather team at Cape Canaveral predicts an 80% chance of favorable weather at the launch site Wednesday morning.
The mission, known as Crew-3, is SpaceX’s third operational crew rotation flight to the space station under a $2.6 billion contract with NASA.
NASA commander Raja Chari, pilot Tom Marshburn, mission specialist Kayla Barron, and European Space Agency astronaut Matthias Maurer are heading to the space station for a nearly six-month mission.
Their Crew Dragon “Endurance” spacecraft is scheduled to dock with the space station’s Harmony module around 22 hours after launch Wednesday.
After docking at the space station, Chari and his crewmates will be greeted by the seven astronauts and cosmonauts currently living on the outpost. The Crew-3 astronauts will replace an outgoing team of four space fliers who arrived at the space station April 24 on SpaceX’s Crew-2 mission.
Crew-2 commander Shane Kimbrough, pilot, Megan McArthur, Japanese astronaut Akihiko Hoshide, and ESA astronaut Thomas Pesquet will brief the new crew on life and work at the space station during a handover period lasting a few days.
Kimbrough’s crew is scheduled to undock from the space station in their Crew Dragon “Endeavour” spacecraft in early November, targeting a splashdown off the coast of Florida after nearly 200 days in orbit, a record for a SpaceX crew capsule.
That will leave behind Chari, Marshburn, Barron, and Maurer at the space station with Russian cosmonauts Anton Shkaplerov, Pyotr Dubrov, and NASA astronaut Mark Vande Hei, who flew to the orbiting lab on Russian Soyuz spaceships.
NASA announced the Crew-3 launch delay announced early Saturday, hours after officials met for a Launch Readiness Review Friday night to verify the Crew Dragon capsule, Falcon 9 launcher, ground system, and engineering teams are ready for the mission.
The review concluded with a “go” to proceed with launch preparations, following NASA’s sign-off on two technical concerns associated with the Crew Dragon’s toilet system.
During a Flight Readiness Review meeting Monday, NASA engineers said they wanted more time analyzing information from SpaceX on a modification to the Crew Dragon spacecraft’s waste system after running into a problem with the unit on the most recent Dragon crew flight, the all-civilian Inspiration4 mission.
A glued joint in the toilet became disconnected during the three-day Inspiration4 mission, causing urine to leak into a fan system, instead of flowing into a waste tank. The issue caused no significant problem during the Inspiration4 flight, but SpaceX found contamination from the leak under the floor of the spacecraft after it returned to Earth.
For the Crew-3 mission about to launch, SpaceX changed the design of the waste system to go with a welded joint in the urine line, instead of a glued connection. The Crew Dragon spacecraft currently docked to the space station — Crew Dragon Endeavour — still uses the glued joint design, and astronauts found similar contamination under the floor during on-orbit inspections, indicating it had a similar leak as the Inspiration4 capsule.
The Crew-2 astronauts used the Dragon toilet from the time they launched in April until they docked with the space station about 24 hours later. The Crew-2 mission is scheduled to return to Earth next week, a few days after the Crew-3 mission arrives at the station.
NASA this week formally cleared the toilet systems on the Crew-2 and Crew-3 capsules for the upcoming crew rotation.
“One was the final review of the upgrade to the system that was done for Crew-3. And we have fully reviewed those data. That system was fully signed off, and that exception closed a couple of days ago,” said Nicole Jordan, manager of the spacecraft office in NASA’s commercial crew program, in an interview Friday.
“And the second one was the final review of all of the flight rationale for the Crew-2 return and specifically the concern with the weldment and any kind of material might have gotten on it from the operation of that system on Crew-2 ascent to dock. And that closed last night.”
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