NASA boss Jared Isaacman sent staff a letter blasting the Starliner mission that left 2 astronauts stranded in space

• NASA Administrator Jared Isaacman blasted the "troubling" failures of the Boeing Starliner mission.
• In a letter to NASA staff, he said it wasn't initially deemed a mishap due to reputational concerns.
• A report into the mission found "unprofessional behavior," including yelling in meetings.

The head of NASA sent a scathing letter to employees on Thursday, outlining the failures of the botched Boeing Starliner mission that left a pair of astronauts stuck in space.

Jared Isaacman slammed "design and engineering deficiencies" but said the "most troubling failure" was decision-making and leadership.

"If left unchecked, [it] could create a culture incompatible with human spaceflight," he added.

The mission took place in June 2024, flying two NASA astronauts to the International Space Station. However, helium leaks saw Starliner's thrusters malfunction. The mission was supposed to last eight days, but the pair ultimately spent over 90 days in space before returning to Earth on a SpaceX flight.

"We returned the crew safely, but the path we took did not reflect NASA at its best," Isaacman told staff.

Also on Thursday, the incident was formally designated as a "Type A mishap" — the most severe level, on par with the Columbia and Challenger Space Shuttle disasters.

NASA defines such mishaps as those causing more than $2 million in failure costs, the loss of a vehicle or its control, or deaths.

However, a mishap was not initially declared for Starliner, despite a loss of control and, according to Isaacman, "cost thresholds exceeding a Type A mishap by a factor of one hundred," implying a loss of at least $200 million.

This decision was influenced by "concern for the Starliner program's reputation," he added.

Isaacman's letter wasn't entirely gloomy.

He praised the "extraordinary professionalism" of controllers and crew who recovered control of the spacecraft and achieved docking with the International Space Station.

"At that moment, had different decisions been made, had thrusters not been recovered, or had docking been unsuccessful, the outcome of this mission could have been very different," he added.

'Unprofessional behavior' included 'yelling in meetings'

The letter coincided with the publication of the report into the Starliner mission. It's over 300 pages long and details the engineering and cultural problems.

Investigators said there were "times of unprofessional behavior" as NASA and Boeing butted heads on how to bring the astronauts home.

"There was yelling in meetings," one interviewee said. "It was emotionally charged and unproductive." Another said they heard safety engineers being berated "off muted mics."

"It was probably the ugliest environment that I've been in," said another.

The report listed three root causes for the debacle.

Firstly, it said NASA had a "hands-off approach" to setting up the contract, leading to insufficient oversight of Boeing's design and testing.

Then, Boeing didn't verify the propulsion system across all environments and use cases during the design phase, leaving Starliner exposed to conditions for which it wasn't properly certified, the report said.

Lastly, it said the culture at NASA's Commercial Crew Program led to greater acceptance of technical risk and a reluctance to fully challenge Boeing's analyses.

Isaacman said that NASA will continue working with Boeing.

"But to be clear: NASA will not fly another crew on Starliner until technical causes are understood and corrected, the propulsion system is fully qualified, and appropriate investigation recommendations are implemented," he added.

In a statement, Boeing said it was "grateful" to NASA for its "thorough investigation."

"In the 18 months since our test flight, Boeing has made substantial progress on corrective actions for technical challenges we encountered and driven significant cultural changes across the team that directly align with the findings in the report."