The United States space agency NASA and aerospace manufacturer Boeing have agreed to cut down the number of space flights astronauts take via the company’s Starliner capsule from six to four, according to multiple reports.

Reuters reported that NASA in its statement said the original $4.5 billion contract, awarded to Boeing under the agency’s Commercial Crew Program has been revised, with the last two flights of the original six, set to be optional.

A Boeing representative had no immediate comment when contacted by Bloomberg on the same.

Last Boeing mission left Sunita Williams, Butch Wilmore stranded

Eight months after the first and only Starliner crew returned to Earth after a prolonged mission aboard the International Space Station (ISS), following problems with the capsule, NASA on 24 November announced that the deal has been shortened, AP reported.

NASA pilots Sunita Williams and Butch Wilmore were stranded on the ISS and had to return nine months later on a SpaceX flight, after the Boeing Starliner had so many issues, it was ordered to return to Earth empty.

What’s next for Boeing Starliner project?

Since then, the report added that engineers have been working on resolving issues with the Starliner’s thrusters, propulsion system, and other technical faults that caused trouble during the last mission.

“NASA and Boeing are continuing to rigorously test the Starliner propulsion system in preparation for two potential flights next year,” NASA’s commercial crew program manager Steve Stich said in a statement.

The next planned mission, Starliner-1 is schedule no earlier than April 2026 and will be a cargo test run to the ISS. This is still pending additional tests and certification before it is confirmed, the AP report added. If the cargo mission is successful, then NASA will plan crew flight missions with the Starliner before the ISS is decommissioned in 2030.

The Reuters report added that the uncrewed test is the third such for Boeing and has cost the company over $2 billion since 2016.

NASA signed contracts with both Boeing and Elon Musk‘s SpaceX in 2014. The SpaceX contract was worth $2.6 billion and completed its first astronaut mission for NASA in 2020 — till summer 2025 it has completed 12 missions for NASA, the AP report added.

(With inputs from Agencies)