Boeing Starliner docks with space station after encountering new ...

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Boeing’s Starliner mission has safely docked with the International Space Station after navigating new issues that cropped up overnight and Thursday en route to the orbiting laboratory.

Docking occurred at 1:34 p.m. ET. Steps were taken to more firmly secure the connection between Starliner and the space station’s port, and docking was completed about 20 minutes later. Now, mission teams will work toward opening the hatch between the spacecraft and station, estimated to occur at 3:20 p.m. ET.

Once the hatch is open, NASA astronauts Butch Wilmore and Suni Williams will spend the next eight days on the station, joining the seven astronauts and cosmonauts already aboard the station.

“Nice to be attached to the big city in the sky,” Wilmore said after docking was confirmed.

After a successful launch that was a decade in the making, Boeing’s Starliner mission experienced helium leaks and a temporary loss of thrusters during its journey to the space station, according to NASA.

During the final hour of their approach to the space station, Starliner’s crew began to manually pilot the spacecraft in a planned test of Starliner’s manual flight control capability. Five of the reaction control system thrusters failed on the service module, but the duo was able to get four of the thrusters firing again after conducting hot-fire tests.

These smaller thrusters are used as the spacecraft moves closer to the space station so it can make more finely tuned changes to its trajectory. There are 28 total such thrusters located on the service module, or the lower portion of Starliner, which will not return to Earth.

Starliner was expected to dock at the space station by 12:15 p.m. ET, but the thruster issue caused a delay, and the mission moved on to a new docking window.

During testing of the thrusters, Starliner maintained a distance of about 820 feet (250 meters) from the space station until it was deemed “orbit-safe,” away from a 656-foot (200-meter) invisible “keep out” boundary designated to protect the station.

Starliner also faced another issue on its journey: helium leaks.

The space agency said late Wednesday in a post on X, formerly known as Twitter, that two additional helium leaks had been detected on the vehicle. One helium leak had been discovered prior to launch and deemed acceptable.

“Helium is used in spacecraft thruster systems to allow the thrusters to fire and is not combustible or toxic,” according to Boeing.

As of Thursday morning, two of the three leaks have been corrected, according to a live NASA broadcast.

Mission managers polled “go” for rendezvous and docking with the space station, and the leaks are not expected to impact docking, according to the broadcast.

“During all of Starliner’s rendezvous and proximity operations, we’ll keep those propellant manifolds open, but they’ll stay open until docking. Starliner’s currently maintaining plenty of helium reserves,” Boeing aerospace engineer Jim May confirmed Thursday morning in a social media post on X shared by Boeing.

“Currently the helium leak is not a safety issue for the crew, the vehicle or the mission.”

The flight control team will continue to monitor the leak rates in Starliner’s propulsion system and after docking, all of Starliner manifolds were closed per normal plans, according to NASA.

Late night leaks

Just as Wilmore and Williams were about to go to sleep Wednesday night, mission control informed them that they needed to shut down two valves due to the new helium leaks.

“Teams have identified three helium leaks on the spacecraft. One of these was previously discussed before flight along with a management plan,” NASA shared in the post. “The other two are new since the spacecraft arrived on orbit. Two of the affected helium valves have been closed and the spacecraft remains stable.”

A related exchange had taken place earlier on the NASA broadcast.

“Looks like we picked up a couple more helium leaks,” mission control told the astronauts, as heard on the broadcast. Controllers then walked the crew through the plan to shut down the valves.

“Butch, I’m sorry. We’re still getting the story together,” mission control replied.

“We are ready to … find out exactly what you mean by picked up another helium leak, so give it to us,” Wilmore told them.

NASA and Boeing determined the crew was safe and told the duo to go to sleep while they continue to look at the data. The crew was supposed to sleep for nine hours, but the troubleshooting effort cut into an hour of rest time.

“We have some issues to watch overnight when in regards to the helium leaks that was just brought up, and we have a lot of smart people down here on the ground that are going to take a look at this stuff and keep an eye on it, but the vehicle is in a configuration right now where they’re safe to fly,” Boeing aerospace engineer Brandon Burroughs said on the NASA broadcast.

Historic launch

Starliner’s highly anticipated voyage lifted off atop an Atlas V rocket Wednesday at 10:52 a.m. ET from Cape Canaveral Space Force Station in Florida. The historic launch marked the first time the spacecraft has carried a crew to space.

The mission, known as the Crew Flight Test, is the culmination of Boeing’s efforts to develop a spacecraft to rival SpaceX’s Crew Dragon capsule and expand the United States’ options for ferrying astronauts to the space station under NASA’s Commercial Crew Program. The federal agency’s initiative aims to foster collaboration with private industry partners.

The flight marks only the sixth inaugural journey of a crewed spacecraft in US history, NASA Administrator Bill Nelson noted in a May news conference.

“It started with Mercury, then with Gemini, then with Apollo, the space shuttle, then (SpaceX’s) Dragon — and now Starliner,” Nelson said.

Williams also made history as the first woman to fly aboard such a mission.

“This is another milestone in this extraordinary history of NASA,” Nelson said Wednesday after the launch. “And I want to give my personal congratulations to the whole team that went through a lot of trial and tribulation. But they had perseverance and that’s what we do at NASA. We don’t launch until it’s right.”

Just after Wednesday’s launch, NASA officials shared that Williams and Wilmore may enjoy a slightly extended stay aboard the station. The earliest possible landing date is June 14.

“We’ve got a prescribed landing date that goes along with this launch date, but I just want to emphasize that nobody should get too excited about that date,” said Ken Bowersox, associate administrator for NASA’s Space Operations Mission Directorate. “We have to have a lot of conditions that are just right before we bring the Starliner home and we’re going to wait till the conditions are right and we’ve accomplished the test objectives before we do that.”

Weeks of troubleshooting

A number of issues caused the previous crewed launch attempts, on May 6 and June 1, to be scrubbed.

Two hours prior to the launch attempt on May 6, engineers identified an issue with a valve on the second stage, or upper portion, of the Atlas V rocket, which was built by United Launch Alliance, a joint venture between Boeing and Lockheed Martin. The entire stack, including the rocket and spacecraft, was rolled back from the launchpad for testing and repairs.

Teams also worked through a small helium leak within the spacecraft service module and a “design vulnerability” in the propulsion system.

After troubleshooting the initial helium leak in May, mission specialists found it did not pose a threat to the flight. During the launch countdown Wednesday morning, teams monitored the leak and reported no issues.

Starliner was just 3 minutes and 50 seconds from liftoff Saturday afternoon, when an automatic hold was triggered by the ground launch sequencer, or the computer that launches the rocket.

United Launch Alliance technicians and engineers assessed the ground support equipment over the weekend, examining three large computers housed inside a shelter at the base of the launchpad. Each computer is the same, providing triple redundancy to ensure the safe launch of crewed missions.

Engineers isolated the issue that halted Saturday’s launch attempt to a single ground power supply within one of the computers, which provides power to the computer cards responsible for key countdown events, according to an update shared by NASA.

They removed the computer and replaced it with a spare.