SpaceX Crew Dragon Launch To Space Station Delayed To Friday By Weather

Launch of a SpaceX Crew Dragon capsule carrying four astronauts to the International Space Station has been delayed 24 hours to Friday because of bad weather in the Atlantic Ocean where the crew could be forced to ditch in an emergency, NASA announced Wednesday.

Originally scheduled for liftoff from the Kennedy Space Center at 6:11 a.m. EDT Thursday, the flight was reset for 5:49 a.m. Friday, roughly the moment Earth's rotation carries pad 39A in line the space station's orbital path — a requirement for spacecraft trying to rendezvous with a target in low-Earth orbit.

"We're going to have to delay a day, we're not going to be able to launch tomorrow morning," spaceport Director Bob Cabana told reporters. "Although the weather's probably going to look great here at the launch site, we're worried about those downrange winds and wave heights in case of an abort should that happen.

"As soon as this front gets through, it's going to be absolutely beautiful Friday morning, we're going to come out and do it again."

If all goes well Friday, commander Shane Kimbrough, Megan McArthur, European Space Agency astronaut Thomas Pesquet and Japanese flier Akihiko Hoshide will catch up with the space station Saturday, moving in for an automated docking around 5:10 a.m. to kick off a planned six-month stay.

Unlike the space shuttle, which could glide to runways in the United States, Spain or Africa in the event of an in-flight abort, the wingless Crew Dragon is designed to safely splash down in the ocean if its automated escape system is triggered, propelling the craft away from a malfunctioning booster.

Relatively calm seas and winds are required for a safe splashdown and for successful recovery of the Falcon 9's first stage on a barge-like droneship.

While the odds of an in-flight abort are remote, flight rules require acceptable off-shore conditions before a Crew Dragon is cleared for launch. Better weather, both on shore and off, is expected Friday.

"It's not just about launch (weather) when we're launching crew," Benji Reed, director of human spaceflight for SpaceX, said during a pre-flight briefing Tuesday. "We have to worry about the entire ascent trajectory, because if something goes wrong, we want Dragon to be able to escape off of the rocket. And that means they have to be able to come down in the ocean at all points along that potential escape.

"We're looking at winds and wave height and lightning, all kinds of things to make sure it's right."

Kimbrough and his three crewmates are replacing the crew of another Dragon capsule — Michael Hopkins, Victor Glover, Shannon Walker and Japanese astronaut Soichi Noguchi — who were launched to the station last November in the commercial crew program's first operational flight.

Despite the launch delay for their replacements, Hopkins and company still plan to return to Earth next Wednesday as previously planned, splashing down in the Gulf of Mexico at 12:40 p.m. to close out a 164-day mission.

First published on April 21, 2021 / 10:09 AM

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