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Boeing’s Starliner aims to begin its maiden crewed voyage on Saturday, a mission that’s been a decade in the making.
The new spacecraft is expected to lift off atop an Atlas V rocket at 12:25 a.m. ET from Cape Canaveral Space Force Station in Florida. Live coverage of the event will begin at 8:15 a.m. ET on NASA’s website.
Weather conditions are 90% favorable for launch, with winds and cumulus clouds the only concerns, according to Mark Burger, launch weather officer for the 45th Airborne Squadron at Cape Canaveral Space Force Station.
The mission, called the Crew Flight Test, is the result of Boeing’s efforts to develop a spacecraft to rival SpaceX’s Crew Dragon capsule and expand U.S. options to transport astronauts to the space station under NASA’s Commercial Crew Program. The federal agency’s initiative aims to improve collaboration with private sector partners.
If successful, the flight would mark only the sixth inaugural voyage of a crewed spacecraft in U.S. history, NASA Administrator Bill Nelson stated at a press conference in May. Experienced NASA astronauts Butch Wilmore and Suni Williams will be on board.
“It all started with Mercury, then it started with 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 such a mission.
Boeing Crew Flight Test mission objectives
Once in orbit, the Starliner crew capsule carrying Wilmore and Williams will separate from the Atlas V rocket and ignite its own engines. Starliner is expected to travel more than 24 hours to the International Space Station, with docking expected to occur at 1:50 pm ET on Sunday.
Astronauts will test various aspects of the Starliner’s capabilities, including the spacecraft’s thruster performance, how the spacesuits work inside the capsule, and manual piloting when the crew needs to disable the spacecraft’s autopilot.
The astronaut duo will join seven astronauts and cosmonauts already aboard the space station and spend eight days in the orbiting laboratory.
Astronauts will test the Starliner’s “safe haven” feature, which is designed to offer space station crew shelter in case something goes wrong with the space station, according to Steve Stich, NASA’s Commercial Crew Program manager, speaking at a news conference Friday.
When it’s time to return home, Williams and Wilmore will return using the same Starliner capsule and land in an area of the southwestern United States.
Stich said the earliest possible return for Williams and Wilmore is June 10, but other dates are available in case of bad weather.
If the spacecraft does not lift off as planned on Saturday, there are backup opportunities for launches on June 2, June 5 and June 6, according to NASA.
A series of delays
Years of development disruptions, test flight problems and other costly setbacks slowed the Starliner’s path to the launch pad. Meanwhile, SpaceX, Boeing’s rival under NASA’s commercial program, has become the primary transportation provider for the space agency’s astronauts.
This mission could be the last major milestone before NASA evaluates Boeing’s Starliner spacecraft as ready for routine operations to carry 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 something,” Mark Nappi, vice president and program manager for Boeing’s Commercial Crew Program, said in a statement. “We will evolve, and that evolution will start with the Starliner-1 mission, and it will be even better than the mission we are about to fly.”
Just two hours after Starliner’s first crewed launch attempt on May 6, engineers detected a problem with the valve in the second stage, or upper part, of the Atlas V rocket. The entire stack, including the rocket and spacecraft, was retrieved from the launch pad for testing and repair.
Mission crews then reported a small helium leak in the spacecraft service module. The leak was traced to a part in the single reaction control system thruster, called a flange, where helium is used to ignite the thrusters.
The space agency said the leak did not pose a threat to the mission.
“We really looked carefully at what our options were with this particular flange,” he said. “The fuel line, the oxidizer line and the helium line all come into the flange and that makes it problematic to work on. It almost makes it unsafe to work on.”
Instead of building a new one to fix the leak, Stich said, crews decided the helium leak was small enough to be manageable.
“When we looked at this problem, we saw that it is not about trading,” Nappi said. “It came down to: ‘Is it safe or not?’ And it is safe. That’s why we decided we could fly with what we had.”
During the launch countdown, mission teams will watch to see if leakage increases. Nappi said crews have spent the past two weeks evaluating acceptable levels for helium leaks and troubleshooting outlined in the rulebook that engineers will use when assessing the leak Saturday morning.
While evaluating the helium issue, engineers also identified a “design weakness” in the propulsion system; This essentially described a remote scenario in which certain thrusters could fail as the vehicle left Earth’s orbit, without a backup method to get home safely.
NASA and Boeing have since been working with the thruster’s vendor on a backup plan to handle deorbiting should such a situation arise, Stich said at a May 24 press conference.
“We brought back that redundancy for backup capability in the event of a range of failures that were too distant for direct burn,” Stich said.
Following a flight readiness review meeting on May 29, leaders from NASA, Boeing and United Launch Alliance, which built the rocket, “verified that it was ready for launch, including all systems, facilities and crews supporting the test flight,” according to the space agency.
Mission teams also took a close look at the Starliner’s parachutes after a parachute on Blue Origin’s recent crewed suborbital flight failed to fully inflate. Starliner uses components similar to a parachute system, Stich said.
Blue Origin shared flight data with Boeing and NASA, and after evaluating the Starliner’s parachutes, the team deemed them “fit to fly.”
Last minute packaging
Dana Weigel, NASA’s International Space Station Program manager, said the space station experienced an anomaly on Wednesday that Starliner could assist with.
A pump in the station’s urine processing equipment failed.
“This urine processor takes all the crew’s urine and processes it in the first step of the water recovery system,” Weigel said. “It then sends it to a water processor, which turns it into drinking water. “The station was originally designed to be a closed loop.”
The pump was expected to operate until the fall, and a new pump was scheduled to fly on a cargo resupply mission scheduled for August. But the failure of the pump “put us in a position where we had to store a lot of urine,” Weigel said.
Urine now needs to be stored in containers on board. To solve this problem, a replacement pump was quickly installed in the Starliner’s cargo. Since the pump weighed approximately 150 pounds, the crew removed two crew suitcases from the Starliner, which contained clothing and toiletries such as shampoo and soap carefully selected by Wilmore and Williams.
Weigel said that the space station has emergency clothing and toiletries that the astronaut duo will use for their short stay.
NASA astronaut Mike Fincke, who is planned to serve as a pilot on the upcoming Boeing Starliner-1 mission after a successful test flight, said that Wilmore and Williams have been in crew quarantine since the end of April to protect their health before the launch.
“Butch and Suni have complete confidence in our rocket, spacecraft, operations teams and leadership management teams, and they are absolutely ready to go,” he said.
CNN’s Deblina Chakraborty contributed to this report.
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