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Boeing’s Starliner aims to launch its maiden voyage on Saturday, a mission ten years in the making.
The new spacecraft is expected to lift off atop an Atlas V rocket at 12:25 pm ET from the Cape Canaveral Space Force Station in Florida. A live stream of the event will begin at 8:15 a.m. ET on NASA’s website.
Weather conditions are 90% favorable for the launch, with winds and cumulus clouds the only concerns, according to Mark Burger, the 45th Weather Squadron’s launch weather officer at the Cape Canaveral Space Force Station.
The mission, called Crew Flight Test, is the culmination of Boeing’s efforts to develop a spacecraft to compete with SpaceX’s Crew Dragon capsule and expand US options for transporting astronauts to the space station under NASA’s Commercial Crew Program. The federal agency’s initiative aims to foster collaboration with private industry partners.
If successful, the flight would mark only the sixth inaugural flight of a crewed spacecraft in US history, NASA Administrator Bill Nelson noted in a news conference in May. Riding aboard will be veteran NASA astronauts Butch Wilmore and Suni Williams.
“It started with Mercury, then Gemini, then Apollo, the space shuttle, then (SpaceX’s) Dragon — and now Starliner,” Nelson said.
Williams will also make history as the first woman to fly aboard such a mission.
Boeing Crew Flight Test mission goals
After reaching orbit, the Starliner crew capsule carrying Wilmore and Williams will separate from the Atlas V rocket and fire its own engines. Starliner is expected to spend more than 24 hours traveling to the International Space Station, with docking expected to occur at 1:50 pm ET on Sunday.
The astronauts will test various aspects of Starliner’s capabilities, including the performance of the spacecraft’s thruster, how their spacesuits function inside the cavity, and manual piloting in case the crew needs to override the spacecraft’s autopilot.
The astronaut duo will join the seven astronauts and cosmonauts already on board the space station and spend eight days on the orbiting laboratory.
The astronauts will test the Starliner’s “safe haven” capability, which is designed to offer shelter to the space station crew if there is a problem on the space station, according to Steve Stich, manager of NASA’s Commercial Crew Program, who spoke during a news conference today. Friday.
When it’s time to go home, Williams and Wilmore will return using the same Starliner capsule and land at a site in the southwestern United States.
The earliest possible return for Williams and Wilmore is June 10, but other dates are available in case of inclement weather, Stich said.
If the spacecraft does not lift off as planned on Saturday, there are backup opportunities to launch on June 2, June 5 and June 6, according to NASA.
A series of delays
With years of development, test flight problems and other costly obstacles, Starliner’s path to the launch pad has been delayed. Meanwhile, Boeing’s competitor under NASA’s commercial program – SpaceX – is a transportation provider for the space agency’s astronauts.
This mission could be the last major milestone before NASA deems the Boeing Starliner spacecraft ready for routine operations to deliver astronauts and cargo to the space station.
“We look forward to flying this mission. This is a test flight; we know we’re going to learn things,” Mark Nappi, vice president and program manager of the Commercial Crew Program at Boeing, said in a statement. “We’re going to improve, and that improvement starts with the Starliner-1 mission and it’s going to be even better than the mission we’re about to fly.”
Starliner was only about two hours away from its first crewed launch attempt on May 6 when engineers identified a problem with a valve on the second stage, or upper section, of the Atlas V rocket. -includes the rocket and spacecraft, back from the pad for testing and repair.
Then, mission teams reported a small leak of helium within the spacecraft service module. The leak was traced to a part called a flange on one reaction control system thruster, where helium is used to allow the spark plugs to fire.
The space agency said the leak did not pose a mission threat.
“We really looked at our options with this particular meat,” he said. “A fuel line, an oxidizer line and a helium line all go into the flange, making it difficult to work on. It makes it unsafe to work on.”
Rather than resort to fixing the leak, crews determined the helium leak is small enough to be manageable, Stich said.
“When we looked at this problem, it didn’t come down to making trades,” Nappi said. “It came down to, ‘is it safe or not?’ And it is safe. And that’s why we decided we could fly with what we have.”
During the launch countdown, mission teams will monitor the leak to see if it increases. Crews have spent the past two weeks assessing acceptable levels for the helium leak and troubleshooting, which is outlined in the rulebook that engineers will use when assessing the leak Saturday morning, Nappi said.
While considering the helium issue, engineers saw a “design vulnerability” in the propulsion system – essentially identifying a remote scenario where some trucks would fail as the vehicle leaves Earth orbit, with no backup means of returning home safely.
NASA and Boeing have since worked with the thruster vendor to come up with a backup plan for the deorbit burn, should that situation arise, Stich said at a May 24 news conference.
“We’ve restored that redundancy to backup capacity in a very remote series of failures for the direct stream,” Stich said.
After a flight readiness review meeting on May 29, leaders from NASA, Boeing and United Launch Alliance, which built the rocket, declared “launch readiness, including all systems, facilities and crews that support the test flight ,” according to the space agency.
Starliner parachutes were also closely watched by mission teams when one parachute on Blue Origin’s recent subsonic flight failed to fully inflate. Starliner uses components similar to that parachute system, Stich said.
Blue Origin shared flight data with Boeing and NASA, and after evaluating the Starliner parachutes, the team deemed them “good to fly.”
Last minute packing
The space station had an anomaly Wednesday that Starliner could help fix, said Dana Weigel, manager for NASA’s International Space Station Program.
A pump on the station’s urine processor assembly failed.
“That urine processor takes all the staff’s urine and processes in the first stage of a water recovery system,” Weigel said. “It then sends it downstream to a water processor that turns it into drinking water. The station is really designed to be a closed loop.”
The pump was expected to operate until the fall, and another was scheduled to fly aboard a cargo replacement mission planned for August. But the pump failure “put us in a position where we would have to store a lot of urine,” Weigel said.
Now, the urine must be stored on board in containers. To resolve this issue, a replacement pump was quickly swapped into the Starliner cargo. The pump weighs about 150 pounds, so the team removed two crew suitcases from Starliner carrying clothes and toiletries like shampoo and soap that Wilmore and Williams handpicked.
The space station has a contingency supply of generic clothing and toiletries that the astronaut duo will use instead for their short stay, Weigel said.
Wilmore and Williams have been in crew quarantine to protect their health before launch since late April, said NASA astronaut Mike Fincke, who is set to pilot the upcoming Boeing Starliner-1 mission that would follow a successful test flight.
“Butch and Suni have every confidence in our rockets, our spacecraft and our operations teams and leadership management teams, and they are certainly ready to go,” he said.
CNN’s Deblina Chakraborty contributed to this report.
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