Commercial station crew stuck in space awaiting better splashdown weather

The first all-commercial, non-government crew to visit the International Space Station is getting a bit more bang for their buck in the form of bonus days in orbit, thanks to uncertain weather in the splashdown zone off the Florida coast and complex trajectory requirements.

But the holdup getting the Axiom-1 commercial crew back to Earth has thrown a wrench in NASA's carefully planned space station crew rotation sequence, delaying the planned Saturday launch of four long-duration government astronauts aboard a different Crew Dragon spacecraft, the agency said Wednesday.

"Due to unfavorable weather forecasts, we are still assessing when it's safe to bring the #Ax1 mission home from the @Space_Station," NASA tweeted. "A new #Crew4 launch date will depend on this. Stay tuned for updates."

Axiom-1 commander Michael López-Alegría and his three crewmates — Larry Connor, Canadian Mark Pathy and Israeli Eytan Stibbe — were originally expected to undock Tuesday to close out their historic 10-day station visit. But the flight was extended due to weather in the splashdown zone.

Additional back-to-back slips quickly followed, pushing undocking to at least Thursday night. But NASA announced late Wednesday the crew would instead target undocking for Saturday, at 8:35 p.m. EDT, setting up a splashdown off the coast of Florida around 1:46 p.m. Sunday.

Houston-based Axiom Space, the company paying for the Ax-1 mission, said the crew has enough food and other supplies on board to cover the additional days in orbit, and that the cost of the flight took landing delays into account.

In the midst of the Ax-1 delays, Crew-4 commander Kjell Lindgren, pilot Robert Hines, Jessica Watkins and European Space Agency astronaut Samantha Cristoforetti flew to the Kennedy Space Center earlier this week to prepare for blastoff Saturday atop a SpaceX Falcon 9 rocket.

The astronauts strapped in Wednesday and worked through a dress rehearsal countdown. After they left the pad, SpaceX engineers fueled the rocket and carried out a brief first-stage engine test firing to set the stage for launch. But given the Ax-1 delay, a launch Saturday was no longer under consideration.

Late Wednesday, while announcing the revised Ax-1 splashdown target, NASA said the Crew-4 astronauts had tentatively been rescheduled for launch at 4:15 a.m. Tuesday. Additional opportunities are available April 27 and 28.

Kathy Lueders, NASA's space operations chief, said earlier that engineers need two days between the Ax-1 splashdown and the Crew-4 launch to give engineers time to inspect the returning spacecraft and to review re-entry data before clearing the next Crew Dragon for launch.

"We want to provide a two-day gap after return for data reviews and to prepare for launch and stage recovery assets," Lueders tweeted. "We'll make decisions about a new Crew-4 launch date based on safely executing our plans."

The Crew-4 astronauts are replacing four others launched last November in NASA's third operational Crew Dragon flight. A "direct handover" is planned, giving the outgoing Crew-3 astronauts time to familiarize their replacements with station operations before returning to Earth to close out a nearly six-month mission.

But given the Ax-1 entry delay and Crew-4 launch slip, the Crew-3 return faces a possible delay as well.

In:
• Spacewalk
• International Space Station
• NASA