In this photo provided by NASA, astronauts Butch Wilmore, left, and Suni Williams inspect safety hardware aboard the International Space Station on August 9, 2024.
| Photo Credit: AP

NASA decided on Saturday (August 24, 2024) it’s too risky to bring two astronauts back to Earth in Boeing’s troubled new capsule, and they’ll have to wait until next year for a ride home with SpaceX. What should have been a weeklong test flight for the pair will now last more than eight months.

The seasoned pilots have been stuck at the International Space Station since the beginning of June. A cascade of vexing thruster failures and helium leaks in the new capsule marred their trip to the space station, and they ended up in a holding pattern as engineers conducted tests and debated what to do about the trip back.

After almost three months, the decision finally came down from NASA’s highest ranks on Saturday (August 24, 2024). Butch Wilmore and Sunita Williams will come back in a SpaceX spacecraft in February. Their empty Starliner capsule will undock in early September and attempt to return on autopilot.

As Starliner’s test pilots, the pair should have overseen this critical last leg of the journey, with touchdown in the U.S. desert.

“A test flight by nature is neither safe nor routine,” said NASA Administration Bill Nelson. “And so the decision… is a commitment to safety.”

“This has not been an easy decision, but it is absolutely the right one,” added NASA Associate Administrator Jim Free.

It was a blow to Boeing, adding to the safety concerns plaguing the company on its airplane side. Boeing had counted on Starliner’s first crew trip to revive the troubled program after years of delays and ballooning costs. The company had insisted Starliner was safe based on all the recent thruster tests both in space and on the ground.

Boeing did not participate in Saturday’s news conference by NASA but released a statement: “Boeing continues to focus, first and foremost, on the safety of the crew and spacecraft. We are executing the mission as determined by NASA, and we are preparing the spacecraft for a safe and successful uncrewed return.”

Retired Navy captains with previous long-duration spaceflight experience, Wilmore, 61, and Williams, 58, anticipated surprises when they accepted the shakedown cruise of a new spacecraft, although not quite to this extent.

Before their June 5 launch from Cape Canaveral, Florida, they said their families bought into the uncertainty and stress of their professional careers decades ago. During their lone orbital news conference last month, they said they had trust in the thruster testing being conducted. They had no complaints, they added, and enjoyed pitching in with space station work.

Wilmore’s wife, Deanna, was equally stoic in an interview earlier this month with WVLT-TV in Knoxville, Tennessee, their home state. She was already bracing for a delay until next February: “You just sort of have to roll with it.”

There were few options.

The SpaceX capsule currently parked at the space station is reserved for the four residents who have been there since March. They will return in late September, their stay extended a month by the Starliner dilemma. NASA said it would be unsafe to squeeze two more into the capsule, except in an emergency.

The docked Russian Soyuz capsule is even tighter, capable of flying only three — two of them Russians wrapping up a yearlong stint.

So Wilmore and Williams will wait for SpaceX’s next taxi flight. It’s due to launch in late September with two astronauts instead of the usual four for a routine six-month stay. NASA yanked two to make room for Wilmore and Williams on the return flight in late February.

NASA said no serious consideration was given to asking SpaceX for a quick stand-alone rescue. Last year, the Russian Space Agency had to rush up a replacement Soyuz capsule for three men whose original craft was damaged by space junk. The switch pushed their mission beyond a year, a U.S. space endurance record still held by Frank Rubio.

Starliner’s woes began long before its latest flight.

Bad software fouled the first test flight without a crew in 2019, prompting a do-over in 2022. Then parachute and other issues cropped up, including a helium leak in the capsule’s propellant system that nixed a launch attempt in May. The leak eventually was deemed to be isolated and small enough to pose no concern. But more leaks sprouted following liftoff, and five thrusters also failed.

All but one of those small thrusters restarted in flight. But engineers remain perplexed as to why some thruster seals appear to swell, obstructing the propellant lines, then revert to their normal size.

These 28 thrusters are vital. Besides needed for space station rendezvous, they keep the capsule pointed in the right direction at flight’s end as bigger engines steer the craft out of orbit. Coming in crooked could result in catastrophe.

With the Columbia disaster still fresh in many minds — the shuttle broke apart during reentry in 2003, killing all seven aboard — NASA embraced open debate over Starliner’s return capability. Dissenting views were stifled during Columbia’s doomed flight, just as they were during Challenger’s in 1986.

Despite Saturday’s decision, NASA isn’t giving up on Boeing.

NASA went into its commercial crew program a decade ago wanting two competing U.S. companies ferrying astronauts in the post-shuttle era. Boeing won the bigger contract: more than $4 billion, compared with SpaceX’s $2.6 billion.

With station supply runs already under its belt, SpaceX aced its first of now nine astronaut flights in 2020, while Boeing got bogged down in design flaws that set the company back more than $1 billion. NASA officials still hold out hope that Starliner’s problems can be corrected in time for another crew flight in another year or so.

NASA today picked Elon Musk’s SpaceX to bring back Sunita Williams and Barry Wilmore from space next year. Eighty days ago, the two astronauts arrived at the International Space Station aboard Boeing’s Starliner for an 8-day mission. They were forced to extend their stay because of major technical issues with the Boeing capsule.

The astronauts are expected to return in February next year, after spending a total of eight months in orbit, on a SpaceX Crew Dragon spacecraft due to launch next month as part of a routine astronaut rotation mission.

NASA chief Bill Nelson said Starliner’s propulsion system is too risky to carry its first crew home. Starliner will undock from the ISS without a crew and attempt to return to Earth as it would have with astronauts aboard.

The space agency’s decision to pick Boeing’s top space rival marked a fresh setback to the Starliner test mission. Boeing had hoped the mission would redeem the troubled program after years of development problems and over $1.6 billion in budget overruns since 2016.

Nelson said he discussed the agency’s decision with Boeing’s new CEO Kelly Ortberg.

The SpaceX Crew-9 mission will take off in late September, but carrying only two passengers instead of the originally planned four.

It will remain moored to the ISS until its scheduled return in February, bringing back its own crew members plus their two stranded colleagues.

The veteran NASA astronauts, both former military test pilots, became the first crew to ride Starliner on June 5 when they were launched to the ISS.

Starliner’s propulsion system suffered multiple glitches beginning in the first 24 hours of its flight to the ISS, triggering months of cascading delays. Five of its 28 thrusters failed and it sprang several leaks of helium, which is used to pressurise the thrusters.

Since Starliner docked to the ISS in June, Boeing has scrambled to investigate what caused its thruster mishaps and helium leaks. The company arranged tests and simulations on Earth to gather data that it has used to try and convince NASA officials that Starliner is safe to fly the crew back home.

But results from that testing raised more difficult engineering questions and ultimately failed to quell NASA officials’ concerns about Starliner’s ability to make its crewed return trip – the most daunting and complex part of the test mission.

Washington:

Two NASA astronauts who flew to the International Space Station in June aboard Boeing’s faulty Starliner capsule will need to return to Earth on a SpaceX vehicle early next year, NASA said on Saturday, deeming issues with Starliner’s propulsion system too risky to carry its first crew home.

The agency’s decision, tapping Boeing’s top space rival to return the astronauts, is one of NASA’s most consequential in years. Boeing had hoped the test mission would redeem the Starliner program after years of development problems and over $1.6 billion in budget overruns since 2016.

Boeing is also struggling with quality issues on production of commercial planes, its most important products.

Veteran NASA astronauts Butch Wilmore and Sunita Williams, both former military test pilots, became the first crew to ride Starliner on June 5 when they were launched to the ISS for what was expected to be an eight-day test mission.

But Starliner’s propulsion system suffered a series of glitches beginning in the first 24 hours of its flight to the ISS, triggering months of cascading delays. Five of its 28 thrusters failed and it sprang several leaks of helium, which is used to pressurize the thrusters.

In a rare reshuffling of NASA’s astronaut operations, the two astronauts are now expected to return in February 2025 on a SpaceX Crew Dragon spacecraft due to launch next month as part of a routine astronaut rotation mission. Two of the Crew Dragon’s four astronaut seats will be kept empty for Wilmore and Williams. 

Starliner will undock from the ISS without a crew and attempt to return to Earth as it would have with astronauts aboard. 

Boeing struggled for years to develop Starliner, a gumdrop-shaped capsule designed to compete with Crew Dragon as a second U.S. option for sending astronaut crews to and from Earth’s orbit.

Starliner failed a 2019 test to launch to the ISS uncrewed, but mostly succeeded in a 2022 do-over attempt where it also encountered thruster problems. Its June mission with its first crew was required before NASA can certify the capsule for routine flights, but now Starliner’s crew certification path has been upended.

Since Starliner docked to the ISS in June, Boeing has scrambled to investigate what caused its thruster mishaps and helium leaks. The company arranged tests and simulations on Earth to gather data that it has used to try and convince NASA officials that Starliner is safe to fly the crew back home.

But results from that testing raised more difficult engineering questions and ultimately failed to quell NASA officials’ concerns about Starliner’s ability to make its crewed return trip – the most daunting and complex part of the test mission.

NASA’s decision, and Starliner’s now-uncertain path to certification, will add to the crises faced by new Boeing CEO Kelly Ortberg, who started this month with the goal to rebuild the planemaker’s reputation after a door panel dramatically blew off a 737 MAX passenger jet in midair in January.

(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)

In June 2024, when the Boeing Starliner spacecraft carried NASA astronauts Sunita Williams and Barry Wilmore to space, it was going to be a short eight-day mission. However, it’s been 80 days since the launch and the two astronauts are yet to return.

Launched on June 5, the test flight landed on the International Space Station (ISS) on June 6. Ms Williams and Mr Wilmore are still stuck in space, while the date of their return journey remains undecided. Some technical problems with the Boeing Starliner have left NASA unable to move on with their plans.

What is the mission?

The purpose of the Boeing Starliner mission was to demonstrate the spacecraft’s capability to safely carry people to and from the ISS. As part of NASA’s Commercial Crew Program, Boeing, the aerospace company, views this trip as critical to its goal of joining Elon Musk’s SpaceX in offering regular crew transportation services to the space agency.

Why is the Boeing Starliner still stuck in space?

Helium leaks: The spacecraft’s service module reported several tiny helium leaks making it unsafe for travel. Helium is essential to preserving the spacecraft’s structural integrity and manoeuvrability.

Thruster problems: The propulsion system of the spaceship experienced malfunctions with five of its thrusters. These components are essential for space travel and docking.

Valve issues: Multiple issues with a valve responsible for regulating the flow of oxidizers were detected. The valve is essential for propulsion.

What is NASA doing? 

NASA and Boeing engineers are attempting to resolve the issues with the spacecraft. They are examining data from the spacecraft’s propulsion system and are testing the spacecraft thrusters. Several scenarios are being explored using simulators stationed on the ground to find and address the problems.

NASA will hold a press conference later on Saturday to update the world on when the two astronauts may return to Earth. 

Washington:

Boeing’s first crewed Starliner test flight, carrying NASA astronauts Sunita Williams and Barry Wilmore, has been stuck in space for the past two months. The journey, originally an eight-day mission, has now completed 80 days in space.

NASA officials will provide an update on the mission on Saturday, August 24, detailing their strategy for bringing the astronauts back to Earth. The press conference is set for Saturday at 1 p.m. EDT (1700 GMT). It will be headlined by NASA Administrator Bill Nelson along with other agency representatives. You can watch the live telecast on the NASA app and its YouTube channel at 10:30 pm IST.

Sunita Williams and Barry Wilmore were sent on an eight-day mission to the International Space Station (ISS) on June 5. However, the pair’s return was postponed indefinitely due to helium leaks and many thruster malfunctions on the spacecraft. 

To comprehend the technical issues, NASA and Boeing have collected information about the spacecraft’s helium and propulsion systems from both space and the ground.

According to the official statement, the review scheduled for later on Saturday will cover a mission status report, closeout actions, and a review of technical data. It will also certify flight rationale to proceed with undocking and return from the space station.

Meanwhile, Sunita Williams and Barry Wilmore have integrated with the rest of the crew currently aboard the International Space Station and are conducting routine tasks.

As part of its private Crew Program, NASA selected two private spacecraft, Boeing’s Starliner and SpaceX’s Crew Dragon capsule, to transport astronauts to and from the International Space Station. The present trip of Boeing’s Starliner, the Crew Flight Test, is the company’s first of at least six scheduled crewed missions for NASA under the multibillion-dollar contract. SpaceX has performed nine crewed flights for NASA since 2020 apart from numerous private missions of its own).

Washington, United States:

NASA said on Wednesday that astronauts delivered to the International Space Station by Boeing’s Starliner could return on SpaceX’s Crew Dragon in February 2025 if Starliner is still deemed unsafe to return to Earth.

Starliner spacecraft launched in June carrying two astronauts to the ISS in a high-stakes test mission required before NASA can certify the spacecraft for routine astronaut flights.

But the mission, initially expected to last about eight days, has been drawn out far longer by an array of problems with the craft’s propulsion system that Boeing and NASA have been scrambling to fix.

Those problems have called into question Starliner’s ability to safely return to Earth its crew, veteran NASA astronauts Butch Wilmore and Suni Williams. NASA has been examining whether a Crew Dragon capsule will have to bring them home instead.

(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)

New Delhi:

Astronaut Sunita Williams’ mission may have been prolonged because of glitches in the Boeing Starliner capsule but she is in the “safest possible place in space” and there is no cause for concern, ISRO Chairman S Somanath has said. 

Speaking exclusively to NDTV on Tuesday, Mr Somanath was asked whether he had any concerns about Indian astronaut Group Captain Shubhanshu Shukla going to the International Space Station (ISS) later this year, given that Ms Williams – an Indian-origin astronaut – has been there for two months on what was supposed to be a mission lasting approximately a week.

“That has nothing to do with the ISS. Apart from Ms Williams, there are eight other astronauts, many of whom have been there for a long time. Their plan of return is with some other missions that are yet to be scheduled. The only question with Ms Williams is that she had planned for a week-long mission and should have returned aboard the Boeing starliner, which has faced some technical issues,” the ISRO chief said. 

“But they are in the safest place possible in space, which is the International Space Station, so there is no cause for concern. There is definitely a way to bring them back. Either on the Starliner or some other capsule, two of which are already there. But to bring back a crew trained on one craft with certain specifications to another… switching is not easy, it has never been done before. There are technical issues to be addressed which can be done by the concerned people,” he added.

Mr Somanath emphasised, however, that his expectation is that Ms Williams and her fellow astronaut on the Starliner mission, Barry “Butch” Wilmore, would return to Earth on the Boeing capsule itself. 

“They may delay it to make sure that the Starliner becomes cleared for return,” he said. 

Ms Williams and Mr Wilmore took off aboard the Boeing Starliner in June and have been at the ISS since the sixth of that month. The Starliner has faced glitches in the propulsion system following a series of helium leaks and the astronauts, NASA and Boeing are working on a fix to get them back to Earth. 

Group Captain Shukla will be on the Indo-US Axiom-4 mission to the International Space Station, which is expected to launch in early 2025. According to ISRO, the Gaganyatri will undertake selected scientific research and technology demonstration experiments on board the ISS as well as engage in space outreach activities. The mission will be led by Dr Peggy Annette Whitson, who is America’s most experienced astronaut. 

Story so far: Veteran American astronauts Sunita Williams and Barry (Butch) Wilmore, are still docked with the International Space Station (ISS) since June 6 after facing delays, space debris threats, helium leaks and technical glitches on the Starliner spacecraft on which they travelled.

The U.S Space Agency — National Aeronautics and Space Administration (NASA) — held a ‘space-to-earth’ news conference with the two astronauts on July 10 to receive an update on their mission’s progress. Both astronauts said they ‘felt confident’ that they could return to Earth on Starliner itself.

Also read | How Boeing can bring NASA’s Sunita Williams, Barry Wilmore back to Earth

“I have a real good feeling in my heart that this spacecraft will bring us home, no problem,” said Ms. Williams, while Mr. Wilmore said, “That mantra you’ve heard, failure is not an option.” He added that both crew members were staying on the ISS to test the spacecraft

NASA along with the space capsule’s manufacturer Boeing is evaluating Starliner’s propulsion system and the five small helium leaks in the service module. The team is conducting ground tests on identical thrusters at New Mexico’s White Sands Missile Range while another investigation is underway at NASA’s Marshall Space Flight Center in Alabama to determine why the propulsion system’s seal failed, leading to helium leaks.

The continued delay in Ms. Williams and Mr. Wilmore’s safe return, which was initially scheduled to begin on June 18, has piqued concerns across the world, including India. Apart from Ms. Williams and Mr. Wilmore, NASA astronauts Michael Barratt, Matt Dominick, Tracy C. Dyson, Jeanette Epps and Russian Cosmonauts Nikolai Chub, Alexander Grebenkin, and Oleg Kononenko are aboard the ISS.

Here’s a look at the attempted launches, what went wrong, and current efforts for the crew’s safe return

Starliner’s attempted launches and success

Sunita Williams, 58, is the pilot of NASA’s Crew Flight Test mission aboard Boeing’s Starliner space capsule. The mission is a joint venture between NASA and American private space players to open up commercial travel to low-Earth orbits and the ISS to more people for scientific and commercial purposes.

United Launch Alliance, a joint venture by Boeing and Lockheed Martin manufactured the Atlas V rocket which transported the astronauts via Boeing’s space capsule Starliner to the ISS. With this, NASA will have a second space capsule option (apart from SpaceX’s Crew Dragon), which has a crew module which can house up to seven astronauts and a non-reusable service module which houses the equipment and systems (air, temperature controls, water supply etc) needed for a stay in space.

The first crewed test flight of Starliner with the above-mentioned astronauts was scheduled for May 6 for a week-long stay at the ISS. However, the flight was scrapped less than two hours before the launch after an issue was detected in an oxygen relief valve of the rocket’s second stage. All launch activities were suspended and the flight was postponed to May 17.

A helium leak was detected in a thruster in Starliner’s service module, further postponing the launch to June 1. On that day, the ground launch sequencer, the computer which launches the rocket, triggered an automatic hold stopping the countdown clock three minutes fifty seconds before the launch.

On June 5, Starliner was finally launched successfully from NASA’s Space Launch Complex-41 at Cape Canaveral Space Force Station in Florida and the two astronauts docked with the forward-facing port of the ISS. During their week long stay, the astronauts were tasked with verifying if Starliner was performing as intended by conducting tests on the various control systems and manoeuvring the thrusters. Prior to take-off, a small helium leak was noticed in the space capsule’s propulsion system but not deemed serious.

What went wrong?

En-route to the ISS, four more small helium leaks sprung up. Both NASA and Boeing officials reviewed flight data to find out the cause of the leaks. On June 6, NASA’s Commercial Crew Program manager Steve Stich admitted that similar thruster issues were revealed during the spacecraft’s uncrewed test flight in 2022, adding, “thought we had fixed that problem,” at a press conference.

The undocking and return journey of Starliner, which was scheduled for June 18, was postponed to June 22, then June 25 and later to July 2.

Mr. Stich opined that thruster issues may have been caused overheating when fuel was burned during the space capsule’s rendezvous with the ISS. According to CNN, the Starliner’s service module has 28 reaction control thrusters, of which five have failed during flight. Four were brought back online eventually.

The Starliner, which had its first uncrewed Orbital test flight in 2019, faced a software glitch, leaving the space capsule in the wrong orbit before it returned to ground without docking with the ISS. In 2022, the space capsule successfully conducted its first uncrewed test flight when it docked with the ISS and then undocked four days later to return to Earth. This flight too faced issues with the thrusters.

What is causing the delay?

Apart from technical issues, the crew also faced a debris collision threat on June 28. The US Space Command alerted the six astronauts onboard the ISS to execute ‘safe haven’ procedures i.e. crew members board the spacecraft they arrived in, in case an emergency departure is needed. This was necessitated after a defunct Russian satellite (RESURS-P1) broke into more than 100 pieces of debris in an orbit near the ISS. Ms. Williams and Mr. Wilmore were forced to board the Starliner to take shelter for an hour before they resumed their activities on the ISS.

On July 2, NASA said that the spacecraft was in good shape to remain docked to the ISS for over 45 days (its upper limit), giving the ground teams of NASA and Boeing time to conduct simulations and tests on the thrusters. Analysis is also underway to determine why several helium leaks have arisen in the capsule, said NASA. Currently, NASA has not set any end date to the mission, making the extension indefinite.

How will the crew return?

In the July 10 press conference, NASA has said, that if absolutely necessary, Starliner would be capable of returning to Earth – acting as an escape pod. Moreover, NASA also has the option of ferrying Mr. Wilmore and Ms. Williams to Earth aboard Crew Dragon. The SpaceX spaceship transported four astronauts to the ISS in March and is capable of fitting more people in case of an emergency. However, such an option has would be a last resort in case Starliner is deemed non-functional.

But NASA has reiterated its confidence in the Starliner to return the duo, dropping the option of using the Crew Dragon.

Indian-origin Sunita Williams has said she is looking forward to meeting the Indian astronauts who will fly to the International Space Station (ISS).

The Indian Space Research Organisation (ISRO) is working on a joint project with the US’ National Aeronautics and Space Administration (NASA) to send an Indian astronaut to space. Of the four astronauts that India had chosen, two will be sent to NASA for training, and one of them will be selected for the space mission, ISRO chief Dr S Somanath told NDTV last month.

The two space agencies have also collaborated for NISAR (NASA ISRO Synthetic Aperture Radar), a joint Earth-observation mission.

“India and the US have had much success working together to explore the stars. And our future together could not be brighter,” Sunita Williams said in her video message to the US embassy in Delhi on America’s Independence Day from the ISS, which orbits some 400 kilometers above Earth.

Ladies and gentlemen, brace yourselves for a show-stopping moment! Straight from the International Space Station, we had a special message from the incredible astronauts @Astro_Suni, Tracy Dyson, and @Astro_Jeanette for our space-themed national day celebration in New Delhi last… pic.twitter.com/PsG56LlzVB

— U.S. Embassy India (@USAndIndia) July 11, 2024

She is currently stuck on the ISS due to a problem-plagued Boeing Starliner for almost a month.

“NASA and the ISRO continue to work toward the launch of NISAR, which will launch from India this year to measure changes in our planet’s surface,” she said.

“After returning to Earth, we look forward to meeting Indian astronauts training at NASA’s Johnson Space Center in Houston, Texas. Our partnership with India and the countries around the world will help expand humanity’s reach for the sky,” Williams added.

She was joined by her fellow astronauts Tracy C Dyson and Jeanette J Epps.

NASA To Train 2 Indians, Send One Of Them To Space

The ISRO’s work to send an astronaut to space in a joint project with NASA is going on as scheduled, the Indian space agency’s chief Dr S Somanath told NDTV in an exclusive interview on June 29.

Of the four astronauts that India had chosen, two will be sent to the National Aeronautics and Space Administration (NASA) for training, and one of them will be selected for the space mission, he said.

“Similarly, the other two will also get training of a different kind… So all four of them will go through certain levels of training through this programme. Many engineers will also be trained by NASA to handle other aspects of space flight,” Dr Somanath said.

He said the ISRO’s eventual goal is human space flight, and the learnings from the whole programme with NASA will feed into the Indian space agency’s experience in finally sending humans to space.

“When we get the capability, if a head of state wants to fly to space, for example, it must be on our vehicle, from our land. I will wait for our Gaganyaan to be ready, to be proven, to be qualified to do that,” the ISRO chief told NDTV when asked whether key leaders would be eligible to fly to space in the far future.

Washington:

A pair of US astronauts stuck waiting to leave the International Space Station said Wednesday they were confident that the problem-plagued Boeing Starliner they rode up on would soon bring them home, even as significant uncertainties remain.

Butch Wilmore and Sunita Williams blasted off on June 5 aboard the brand new spaceship that NASA is hoping to certify to ferry crews to-and-from the orbital outpost.

They docked the following day for what was meant to be roughly a week-long stay, but their return was pushed back because of thruster malfunctions and helium leaks that came to light during the journey.

No date has been set for the return, but NASA officials said Wednesday they were eying “late July.”

Asked during a live press call from the station whether they still had faith in the Starliner team and the spaceship, mission commander Wilmore replied: “We’re absolutely confident.”

“I have a real good feeling in my heart that the spacecraft will bring us home, no problem,” added Sunita Williams.

She said they were continuing to enjoy their time aboard the ISS, performing tasks like changing out the pump on a machine that processes urine back into drinking water, and carrying out science experiments such as gene sequencing in the microgravity environment.

They have also tested Starliner as a “safe haven” vehicle in case of problems aboard the ISS and checked out how its life support performs when four people are inside.

Lingering uncertainty

Before Wilmore and Williams can come home, however, engineering teams need to run more simulations of similar thrusters and helium seals on the ground, to better understand the root causes of some of the technical issues Starliner experienced — and modify the way it will fly down, if necessary.

It was known there was one helium leak affecting the spaceship before the launch, but more leaks emerged during the flight. Helium, while non-combustible, provides pressure to the propulsion system.

What’s more, some of Starliner’s thrusters that provide fine maneuvering initially failed to kick in during its approach to the station, delaying docking.

Engineers are not sure why the craft’s computer “deselected” these thrusters, though they were able to restart all but one of them.

In a subsequent press call, Boeing executive Mark Nappi told reporters that the “working theory” for the thruster malfunction was overheating due to excessive firing.

Theories on the cause of the helium leaks ranged from debris entering the propulsion system to Boeing possibly installing seals that were undersized for the task.

NASA and Boeing insist Starliner could fly home in case of an emergency, particularly since the problems affected only certain thrusters that control orientation.

They have no concerns over any of the more powerful thrusters responsible for the “deorbit burn” that will bring the spaceship back.

But much remains unclear — including whether the orientation control thrusters that malfunctioned have become degraded, which would make it necessary to rely on other thrusters during descent, NASA official Steve Stich said.

He insisted that NASA wasn’t yet considering bringing Williams and Wilmore back on a SpaceX Crew Dragon, in what would amount to a major humiliation for the aerospace giant Boeing, whose reputation has taken a hit in recent years over the safety crisis affecting its commercial jets.

“The prime option today is to return Butch and Suni on Starliner,” said Stich, while conceding that a return flight on a SpaceX spaceship can’t be ruled out.

In 2014, both SpaceX and Boeing were awarded multibillion-dollar contracts by NASA to develop crewed spaceships after the retirement of the Space Shuttle program. SpaceX carried out a successful crewed test in 2020 and has flown dozens of people since.

(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)