WASHINGTON — NASA and SpaceX are in the final phases of preparations for a commercial crew test flight that will carry two NASA astronauts to the International Space Station for an extended stay.
During a series of briefings May 1, NASA officials and SpaceX executives expressed excitement about the upcoming Demo-2 mission, scheduled for launch from the Kennedy Space Center May 27, despite some outstanding reviews and tests remaining before launch.
“I can’t tell you how exciting of a day this is for us. Gwynne and I have been waiting for this for a while,” said Kathy Lueders, manager of NASA’s commercial crew program, who participated in one briefing with SpaceX President Gwynne Shotwell.
On the Demo-2 mission, a Crew Dragon spacecraft will launch on a Falcon 9 rocket from KSC with NASA astronauts Bob Behnken and Doug Hurley on board. The spacecraft will dock with the station less than 24 hours later.
What’s not yet clear is how long the spacecraft, and Behnken and Hurley, will remain on the ISS. In a blog post posted shortly before the briefings, NASA Administrator Jim Bridenstine confirmed the mission will be extended because the station currently has on board just one NASA astronaut, Chris Cassidy, and two Russian cosmonauts. “We have extended the planned length of the Demo-2 mission from a standard test flight to ensure Behnken and Hurley can participate as Expedition 63 crew members to safely maintain and operate the station,” he wrote.
The exact length of that mission has yet to be determined. “It is a trade-off,” said Kirk Shireman, NASA ISS program manager, between getting the spacecraft back quickly to complete its certification and providing additional crew time on the station for maintenance and research.
The length of the mission will be linked to when the next Crew Dragon mission, called Crew-1, will be ready to fly. “What we would like to do, from a station perspective, is to keep them on orbit as long as we can until that Crew-1 vehicle is just about ready to go, bring Demo-2 home, allow that certification work to be completed and launch Crew-1,” he said.
In a later briefing, Steve Stich, deputy manager of NASA’s commercial crew program, said the minimum length of the Demo-2 mission, barring unforeseen problems, would be about a month. The maximum length is 119 days, driven by the projected degradation of the solar panels on the Crew Dragon spacecraft. Once the spacecraft is docked, controllers will “wake up” the spacecraft weekly to test the performance of its solar arrays and other systems.
“We would like to fly a mission that is as long as we need to for a test flight, but also support some of the space station program needs,” he said.
Behnken and Hurley, who originally planned to fly a much shorter test flight, did augment their preparations with refresher training for ISS systems that, for Behnken, included training for a spacewalk, if needed. The top priority for the mission is to check out Crew Dragon, but “our next step to try to offload Chris Cassidy,” Behnken said. “There’s a lot of work and activity that can be done in the U.S. segment, certainly more than one person can accomplish on their own.”
NASA and SpaceX are also wrapping up final checks of the spacecraft and reviews. Shotwell said one final test of the Mark 3 parachute system for Crew Dragon was slated for later in the day. “We’re looking forward to finishing that test and getting that item closed out,” she said. SpaceX, in a tweet later in the day, confirmed the test had been carried out, apparently successfully.
Lueders said that NASA had completed its review of an engine anomaly during a Falcon 9 launch of Starlink satellites in March, where one of the nine Merlin engines in the rocket’s first stage shut down prematurely. “We have reviewed the anomaly resolution of the Starlink launch, and actually have cleared the engines on our vehicle,” she said. “That is behind us right now.”
There are still a series of reviews in the weeks ahead, as well as addressing issues that come up during launch vehicle and spacecraft processing. There will be a flight test readiness review at SpaceX May 8 and at NASA May 11, she said. A NASA flight readiness review is scheduled for May 20.
While the commercial crew program is designed to end NASA’s reliance on Russia for getting astronauts to and from the station, delays have forced NASA to purchase additional seats. Bridenstine said at a briefing that the agency was in final negotiations with Roscosmos for a seat on a Soyuz flight in October as a backup for any additional delays.
“We’re getting close to finalizing that deal, and I think it’s within days of being signed,” he said, with price currently the key issue being negotiated. He said NASA will wait to evaluate the performance of the Demo-2 spacecraft before deciding if the agency needs to also buy a Soyuz seat for a flight in the spring of 2021.
Bridenstine also reiterated a plea he made during a briefing a week earlier for the public to watch the launch from home, even as the state of Florida starts to ease restrictions imposed to slow the spread of COVID-19.
“The challenge we’re up against right now is we want to keep everybody safe. That’s the number one, highest priority of NASA,” he said. “So we’re asking people not to travel to the Kennedy Space Center. That makes me sad to even say it.”
“Having large crowds of hundreds of thousands of people at the Kennedy Space Center, now is not the time for that,” he continued. “We don’t want an outbreak.”
The Demo-2 astronauts, who will go into quarantine about two weeks before launch, won’t have friends or family present for the launch. “It certainly is a disappointing aspect of the pandemic,” said Hurley. “It’s obviously the right thing to do in the current environment.”
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