ORLANDO, Fla., April 20 (UPI) -- SpaceX and NASA plan to send four astronauts to the International Space Station on Thursday from Florida aboard the first reused Crew Dragon capsule to carry people.
Liftoff of the flight-proven spacecraft, Endeavour, and Falcon 9 rocket is planned for 6:11 a.m. EDT from Complex 39 at Kennedy Space Center. The space agency declared the mission "go for launch" after a launch readiness review Tuesday morning.
The mission is part of SpaceX's effort to certify the Dragon capsules for five flights while carrying people, Benji Reed, the company's director of human spaceflight, said during a press conference Tuesday.
"We've worked on a number of components. There are some components that we'll replace. And some, we'll ... see how far we can go [without replacing]" Reed said.
Reed said seeing astronauts with their families recently underlined the need for caution in human spaceflight.
"This is something that we pay a lot of attention to, and we ask ourselves all the time, would we be willing to fly our families on these vehicles, and that's kind of a test for us," he said.
Reed and NASA officials indicated that the weather forecast is mostly favorable around the launch pad Thursday, but waves and wind over the Atlantic Ocean might result in postponement until Friday. That's because the capsule must be able to abort and land in the ocean at any point along its flight path, officials said.
The capsule crew consists of Thomas Pesquet of the European Space Agency, NASA astronauts Shane Kimbrough as mission commander and Meghan McArthur as mission pilot, and Japanese astronaut Akihiko Hoshide.
NASA and SpaceX have tried to think of everything that could go wrong or that requires refurbishment or upgrades to reuse the capsule, Tom Simon, NASA's certification manager for the spacecraft, said in an interview Monday.
"It's often very exciting to make a new spacecraft and try it for the first time," Simon said. "But you have to stay just as vigilant and listen to the hardware in between uses, whether it's a tank or a booster or the engines, or the life support system."
SpaceX Crew Dragon capsules are certified for human spaceflight in NASA Commercial Crew Program, which allows the company to design, build and own the spacecraft. But certification of anything new for the spacecraft continues, Simon said.
Certification "continues on anytime that SpaceX would like to make a change, or we try to add on a new capability," he said.
The Endeavour capsule received propulsion upgrades and greater battery capacity since it flew in May, Simon said.
And the spacesuit McArthur and crew will wear has new zippers, he added, based on feedback from her husband and Hurley who said the zippers sometimes were difficult to close.
When the Crew 2 mission arrives, 11 people will be on board the space station briefly until the Crew 1 mission departs in the SpaceX Dragon capsule Resilience. That is planned for April 28.
Since the orbiting laboratory hasn't had that many people on board in years, the Crew 2 launch will carry more supplies, said Joel Montalban, program manager for the space station.
"We have to find some additional consumables for the extra crew members ... and we'll have some temporary sleeping arrangements for the crew members because we have so many people," Montalban said.
"We have to increase the capacity of our life support systems or oxygen generation or carbon dioxide removal."