KENNEDY SPACE CENTER — More testing needs to be done before a decision can be made to bring NASA astronauts Cmdr. Barry “Butch” Wilmore and pilot Sunita “Suni” Williams home on the trouble-prone Boeing Starliner spacecraft, officials from NASA and Boeing said Wednesday afternoon.

During a teleconference, officials said engineers are still working on the issues that have plagued the maiden crewed flight of Boeing’s Starliner spacecraft. They said the two astronauts may return home at the end of the month, but only after tests have become completed and reviewed.

NASA and Boeing officials summarized the issues that have burdened the Boeing Crew Flight Test mission, which took off on Wednesday, June 5, on a United Launch Alliance Atlas V rocket. Five small helium leaks were discovered in a flange of the spacecraft’s service module’s thruster system. These leaks are believed to be caused by a faulty seal.

The helium is used to help pressurize the thrusters.

One of the five aft reaction control system thrusters that maneuver Starliner to and from the International Space Station has been deselected for the rest of the mission.

All five failed during the approach of the space station on Thursday, June 6, but officials were able to conduct a hot-fire test that saw four of the five being re-selected and working.

Despite the five leaks, officials have said that Starliner has enough helium for the return trip home.

Scroll down to see the timeline of the mission events.

On Wednesday, NASA’s Commercial Crew Program Manager Steve Stich told the media that the Starliner team is conducting hot-fire testing of a spare thruster at the White Sands Test Facility in New Mexico.

This is to help teams determine what the working four thrusters on Starliner can handle on the return trip home, and to better understand what has, and might happen.

The testing will take place in two parts: The uphill phase replicates the flight of the Starliner and its docking with the International Space Station, while the downhill phase will be the undocking from the station and return to Earth.

Boeing’s commercial Crew Program Vice President and Program Manager Mark Nappi also said that spare seals are being tested as well to determine what caused the ones in the Starliner module to leak. He said teams on the ground are trying to replicate what may have happened for there to be five helium leaks.

Once data is collected and ground testing completed, leadership will review the results and then decide when Wilmore and Williams will return home. Stich said they are aiming for the end of this month, but it all depends on the data.

While taking media questions, Stich told Spectrum News that officials would like to see Starliner return to Earth before the NASA-SpaceX Crew-9 mission next month, because the space station only has two docking ports designed for SpaceX’s Dragon spacecraft and Starliner. These ports are found in the Harmony module.

Currently, Starliner is docked on the forward-facing port of the Harmony module, while the Dragon capsule Endeavour, which is being used for the Crew-8 mission, is on the zenith port facing space.

“We really have to free up a port to do the rotation coming up, and one of the two ports need to be free up for that,” said Stich.

Both Nappi and Stich said firmly that Williams and Wilmore are expected to return on Starliner, even though NASA said in a June 16 update that the spacecraft may remain docked for months.

“Based upon current space station resources and scheduling needs, a short duration mission with two astronaut test pilots is sufficient to meet all NASA and Boeing test objectives for CFT, which include demonstrating Starliner’s ability to safely fly operational crewed missions to and from the space station. To protect against unforeseen events with crew transportation to the station, NASA may extend the CFT docked duration up to six months and add an additional astronaut later, if needed,” stated NASA.

What the astronauts had to say

Before the teleconference, the media heard from both Wilmore and Williams in their own press conference as they were floating in the International Space Station.

Wilmore started off the press conference by saying, “the spacecraft performed unbelievably well” during liftoff and docking.

The commander of the mission admitted that there were failures, such as the thrusters not working, and he said both they had to manually control the Starliner craft for more than an hour as the Starliner team back on Earth were trouble shooting.

Eventually, four thrusters did come back online and the Starliner autonomously docked with the ISS on Thursday, June 6, which Wilmore called “impressive.”

Like Wilmore, Williams said the Starliner has performed well and the two have conducted tests, like using it as a safe haven in case of an emergency — like when a Russian satellite broke apart and the astronauts had to seek shelter in late June — and placing two other astronauts inside it.

“We still had a lot of checks for Starliner and they went really well,” she said of the tests.

She stressed that this Starliner mission is a flight test and issues are not uncommon.

Butch said that they both feel confident in using Starliner to return back to Earth, with Williams saying: “I have a really good feeling in my heart that this spacecraft will bring us home.”

The pair were supposed to be aboard the ISS for a minimum of eight days, but due to the issues with Starliner, they have had to stay longer.

The Starliner’s batteries have a shelf life of 45 days, and as of Wednesday, July 10, it is day 35 of the mission. Stich said the batteries are being assessed.

A breakdown of the Boeing Crew Flight Test mission

The maiden crewed mission has seen a string of problems, from launching to docking and attempting to return back to Earth.

Here is a timeline of the issues that has troubled the mission.