Boeing had publicly insisted it was confident in its spaceship, but the absence of its executives from recent NASA press briefings had fueled speculation of a rift.
According to sources cited by the New York Post, meetings between the two sides often descended into yelling and arguments.
Asked to address the claims, Steve Stich, program manager for NASA's Commercial Crew Program, said "anytime you're in a meeting of this magnitude where there's this kind of decision, there is some tension in the room."
"Boeing believed in the model that they had created that tried to predict the thruster degradation for the rest of the flight," he added, but "the NASA team, due to the uncertainty in the modeling, could not get comfortable with that."
"I wouldn't say it was a yelling, screaming kind of meeting," Stich told reporters. "It was a tense technical discussion where we had both sides listening intently to all the data."
Fresh clothes
Despite their extended stay, Wilmore and Williams remain in good spirits and are in touch with their families.
They are no longer dependent on borrowed clothes having been sent better fitting suits during a recent resupply mission, the NASA officials reported.
Starliner is set to depart the ISS on Friday evening US Eastern Time before making a parachute and airbag assisted landing in the western United States early on Saturday morning.
Shortly after undocking, the spaceship will execute a "breakout burn" with its thrusters to ensure it shoots clear of the research station before it continues its onward journey to Earth.
Had the flight been crewed, the ship would have flown closer to the station to capture exterior views, but NASA deemed the risk of collision too great without astronauts on board to manually pilot Starliner if required.
© 2024 AFP