NASA mulls bringing space station crew home before Crew Dragon launch
NASA has ruled out a weekend launch for a SpaceX Crew Dragon carrying four astronauts to the International Space Station, delaying the "Crew-3" flight to Monday at the earliest due to expected bad weather, agency officials said Thursday.
Given an uncertain forecast, the mission managers may opt instead to bring four space station astronauts — Crew-2 — back to Earth first, delaying the Crew-3 launch to later next week.
"Mission teams will make a final decision on whether to prioritize Crew-3's launch or Crew-2's return in the coming days based on the likelihood of favorable conditions for a Crew Dragon splashdown or Crew Dragon launch," NASA said in an afternoon blog post. "NASA and SpaceX also are reviewing the time needed between launch or return operations."
If NASA presses ahead with the Crew-3 launch Monday, liftoff from pad 39A at the Kennedy Space Center would be targeted for 9:51 p.m. EST. If Crew-2 is ordered home first, undocking could come as early as 1:05 p.m. Sunday for a splashdown off the coast of Florida on Monday.
SpaceX requires several days to transition from Crew Dragon recovery operations to a launch campaign and a Monday landing by the Crew-2 astronauts would further delay the launch of their replacements.
It also would prevent a "direct handover" in which an outgoing station crew spends several days with their replacements, familiarizing them with lab operations.
"These are dynamic and complex decisions that change day by day," Steve Stich, NASA's Commercial Crew Program manager, said in the blog post. "The weather in November can be especially challenging, so our goal is to move forward on the plan with the highest probability of mission assurance and crew safety."
Crew-3 astronauts Raja Chari, Thomas Marshburn, Kayla Barron and European Space Agency astronaut Matthias Maurer originally planned to take off October 31. But the flight was delayed to Wednesday because of high waves in the Atlantic Ocean along the Crew Dragon's trajectory to orbit where the crew might have to attempt an emergency landing in an abort.
The flight then was delayed to at least Saturday because of an unspecified medical issue with one of the crew members. In Thursday's blog post, NASA said the medical issue is still being monitored, but it's expected to be cleared by the time Crew-3 launches, whenever that might be.
The launch delay to Monday at the earliest was due to predicted high "liftoff winds, cumulus clouds, and surface electric field constraints" Saturday, NASA said, and unacceptable downrange weather Sunday along the ascent trajectory.
"Mission teams are still monitoring weather conditions for a launch attempt on Monday, Nov. 8," NASA said. "The primary operational concern is strong winds at the pad and unfavorable conditions down range."
In the meantime, the clock is ticking on the Crew-2 Dragon.
The Crew-2 astronauts — commander Shane Kimbrough, Megan McArthur, European Space Agency astronaut Thomas Pesquet and Japanese flier Akihiko Hoshide — were launched to the station on April 23. A Monday splashdown would close out a mission spanning 199 days, just 11 days shy of the spacecraft's 210-day certification.