SpaceX's Falcon 9 B1067.2 and Crew Dragon spacecraft at LC-39A in advance of the Crew-3 mission: slated for liftoff no earlier than 9:03 pm EST on November 10, 2021.Trevor Mahlmann
Crew-3 will carry NASA astronauts Raja Chari, Thomas Marshburn, and Kayla Barron and ESA astronaut Matthias Maurer to the ISS for a long-duration stay.Trevor Mahlmann
Return to Earth will be in the spring of 2022, around when the Crew-4 mission launches.Trevor Mahlmann
The Crew Dragon capsule this time around features the storied NASA "worm" logo.Trevor Mahlmann
NASA and SpaceX had originally hoped to fly the next bunch of astronauts to the International Space Station in late October, but the Crew-3 mission has been subject to a handful of delays due to weather and health issues. But now, the mission managers say Crew-3 is ready to fly on a Falcon 9 rocket, with a liftoff set for 9:03 pm ET on Wednesday (02:03 UTC Thursday).
Four astronauts will launch inside Crew Dragon Endurance for this mission—NASA astronauts Raja Chari, Tom Marshburn, and Kayla Barron, as well as European astronaut Matthias Maurer. After docking with the space station on Thursday, the astronauts will spend about six months in orbit performing a variety of science and maintenance operations.
Weather concerns
Poor weather precluded an initial launch attempt on Halloween. Conditions at the launch site weren't bad, but flight controllers were concerned about high seas and strong winds offshore, where an extra-tropical system raged across the northern Atlantic Ocean. Had there been an emergency during the Falcon 9 rocket launch, the Crew Dragon spacecraft would have had to escape into unacceptably poor surface conditions.
SpaceX's William Gerstenmaier said during a Tuesday night news conference that a drone ship positioned offshore to catch the Falcon 9 first stage after launch, Just Read the Instructions, had been battered by 20- to 25-foot seas over the past week.
"There's been some pretty rough weather off the coast," Gerstenmaier said. "It's been tough on some of our drone ships that are sitting out there waiting to recover the boosters." SpaceX will instead use a backup drone ship for the first-stage recovery and bring Just Read the Instructions into port.
These offshore storms have somewhat subsided, and forecasters now anticipate a 70 percent chance of favorable weather for a liftoff Wednesday evening, with good downrange conditions.
Health problem
In addition to weather, NASA said a "minor medical issue" with one of the four astronauts on the Crew-3 mission also contributed to a three-day delay in the launch attempt. Holly Ridings, chief flight director at Johnson Space Center, said Tuesday night that this problem had been cleared up.
"We don't typically talk about details of individual crew members," Ridings said. "We have an entire health stabilization program. There's multiple folks involved to make sure that we don't take anything to orbit. Obviously, you can understand that in an enclosed environment like the space station, you've just got to be really careful before you leave the Earth to make sure that there's nothing that could happen to them while they are on orbit."
NASA did say the issue was not related to COVID-19.
Parachute issue
Finally, on Tuesday, NASA and SpaceX had to take a careful look at a "lagging" parachute deployment issue. When the Crew-2 mission landed on Monday night, one of the spacecraft's four main parachutes deployed about 75 seconds after the other three.
According to Gerstenmaier, this was not a parachute failure; rather, it can occur with the crowded packing of four parachutes in the top of the Crew Dragon capsule. This has happened during tests and is well understood. Crew Dragon is qualified to come back under three parachutes, and its descent rate was nominal. However, NASA and SpaceX were nonetheless careful to assess the issue.
After Crew-2 landed on Monday night, the lagging parachute was flown by helicopter back to SpaceX's facilities at Kennedy Space Center in Florida and hung off a crane for inspection. This was to determine whether there was any damage that may have caused the lagging deployment.
"Each one of these flights is really a gift for us," Gerstenmaier said. "We're still learning how to operate these vehicles. We're learning how to fly in space. And the way you do that safely is you keep looking at the data and you learn from each and every flight. So we looked at this and we don't see anything as off nominal that concerns us from a parachute standpoint."
Rapid turnaround
NASA and SpaceX really are still learning how to operate Crew Dragon for human spaceflights. It has only been 18 months since the very first human mission, called Demo-2, first took flight on the vehicle. With the successful return of Crew Dragon on Monday night, SpaceX has now safely completed its fourth human spaceflight during that time. It plans to launch its fifth human flight less than 48 hours later.
Originally, the agency had intended to launch Crew-3 before landing the Crew-2 mission. But after weather and health issues intervened, NASA and SpaceX made a quick swap of plans, necessitating the rapid repositioning of launch and landing assets. This is not a small logistical challenge.
But now, the launch and landing teams are set to execute both operations, in reverse order, in less than two days. This speaks well of the resiliency of the Falcon, Dragon, and recovery hardware and teams involved.
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