“We have a strong working relationship with our SpaceX partner,” Kathy Lueders, associate administrator of NASA’s human exploration and operations mission directorate, said in the post. “With the high cadence of missions SpaceX performs, it really gives us incredible insight into this commercial system and helps us make informed decisions about the status of our missions. The teams are actively working this finding on the engines, and we should be a lot smarter within the coming week.”
SpaceX did not respond to a request for comment.
The mission, which had previously been scheduled for Oct. 31, would launch NASA astronauts Michael Hopkins, Shannon Walker, Victor Glover as well as Japanese astronaut Soichi Noguchi to the space station for a stay of about six months.
It would be SpaceX’s first operational mission of flying full crews for extended stays after it successfully completed a shorter test mission with two astronauts in August to verify the performance of the Falcon 9 rocket and Dragon spacecraft.
NASA and SpaceX said that test mission, from launch, to docking to splashdown, went flawlessly. But since then SpaceX said that it had redesigned a portion of the capsule’s heat shield after noticing what Hans Koeigsmann, SpaceX’s vice president of build and reliability, said was “a little more erosion than we wanted to see.” The erosion was in a few small areas where the crew capsule joins the spacecraft’s trunk, an unpressurized cargo hold that is discarded before the spacecraft slams into the atmosphere.
The friction between the thickening air and the speeding spacecraft generates temperatures as high as 3,500 degrees Fahrenheit and engulf the capsule in a fireball. The heat shield covers the bottom of the spacecraft and keeps the crew safe.
Speaking to reporters recently, Koenigsmann stressed that there “was nothing to be concerned with at all times. The astronauts were safe, and the vehicle was working perfectly.”
Earlier this month, SpaceX scrubbed a pair of launches late in the countdown, prompting Musk’s plans for “a broad review of launch site, propulsion, structures, avionics & regulatory constraints this weekend.” He added that he would make a trip to Cape Canaveral “to review hardware in person.”
A launch on Oct. 2 of a GPS satellite for the U.S. Space Force was scrubbed two seconds before liftoff after what Musk described as an “unexpected pressure rise in the turbomachinery gas generator,” which helps power the rocket’s Merlin engines.
A day earlier, SpaceX scrubbed a launch of its Starlink satellites with 18 seconds to go in the count because of a problem with a ground sensor. After scrubbing the Starlink mission, SpaceX bounced back and launched the batch of 60 satellites on Tuesday. Still, SpaceX’s goal is to launch much more frequently, and Musk said on Twitter recently that: “We will need to make a lot of improvements to have a chance of completing 48 launches next year!”
The GPS launch has not yet been rescheduled.
The company’s Falcon 9 rocket has flown more than 90 times, the most of any U.S. rocket currently in operation and is considered a reliable workhorse. NASA uses it to fly cargo and supplies to the International Space Station and has certified it for human spaceflight as well.
But it has had problems. In 2015, a rocket carrying cargo to the station exploded some two minutes into flight after a steel strut failed, causing helium to overpressurize a second stage liquid oxygen tank. Then, in 2016, another exploded while being fueled on the launch pad ahead of an engine test after a helium tank buckled.
Last year, the company lost its Dragon spacecraft in an explosion ahead of an engine test fire. NASA and SpaceX investigated all three incidents and eventually cleared SpaceX to fly again.
Noguchi, a veteran of the three space missions, recently told reporters that it is important “to be diligent and don’t be complacent. We have to ask the right questions at the right time to make sure the space vehicle is safe enough. Of course we trust the system. But as a crew we have to persuade ourselves that this vehicle is safe to fly.”