Starliner 1 and 2: NASA and Boeing Detail Fixes and 2028 Crew Flight

On September 28, 2026, NASA and Boeing used a news conference at Kennedy Space Center to announce that an uncrewed Starliner 1 flight to the International Space Station is targeted for no earlier than December 2026, and that NASA astronaut Woody Hoburg will command the first crewed flight after it, Starliner 2, planned for 2028. NASA Administrator Jared Isaacman, Dana Weigel (manager of NASA's Low Earth Orbit Program), Hoburg and John Mulholland (Boeing's vice president and program manager for Commercial Crew) took part.

Where the program stands

Isaacman acknowledged the program's "notable delays and significant technical issues," including the uncrewed demonstrations and the high-profile mishap during the crew flight test (CFT). He said NASA had taken responsibility for its own contributions to the program's challenges, including its handling of the post-mishap investigation, and pointed to the corrective actions outlined in the report of the program investigation team (PIT). Hoburg thanked leadership for earlier declaring CFT a type A mishap, saying it helped restore trust.

Mulholland said that of 21 CFT in-flight anomalies, 19 are closed, with the rest expected to close in October. Corrective action plans exist for the eight Starliner 1 PIT recommendations, and NASA has approved about 90% of all Starliner human spaceflight certification requirements.

The three propulsion problems

Helium leak. Weigel said the original seal material degraded after long-term exposure to NTO, the oxidizer. The seals were replaced with a new material, chosen from the larger side of the tolerance range. Boeing has made these changes on the Starliner 1 spacecraft, and further seals are in long-duration exposure testing.

Crew module thruster failure. The cause was corrosion. Residual hydrazine propellant combined with carbon dioxide in the atmosphere. Mulholland explained that firing a monopropellant hydrazine thruster leaves a tiny amount of "dribble volume" downstream of the valve, which with carbon dioxide forms carbazic acid. Valves on all 12 crew module thrusters on each of the two spacecraft are being replaced. After each firing, or after landing, vacuum will be pulled on all 12 thrusters, followed by a nitrogen trickle purge. Boeing will hot fire the thrusters before rollout and again while docked to the station.

Service module thrusters. Testing showed the valve poppet extrudes under certain thermal and mechanical conditions. Boeing added thermal shunts and barriers. Mulholland described blankets to close out the thruster pods (the "doghouses"), blankets higher on the thrusters, and low-emissivity tape on propellant lines. He said the thrusters run about 100° cooler. Operationally, an "OMAC off pulsing" approach uses another OMAC pulse rather than reaction control thrusters to trim the vehicle, and the conservative approach burn was reduced. After the test series, a small performance degradation of 1 to 2% remained that could not be bounded by analysis or test, so a poppet redesign will be done before crewed flights.

Hoburg said the PIT identified three organizational root causes, one being inadequate systems engineering and integration that created gaps in hardware qualification. In the helium and crew module cases, he said, the unqualified environment was on the ground, and the hardware damage occurred before liftoff.

Starliner 1

Starliner 1, uncrewed, is planned for the December–January timeframe. It will fly the thermal shunts and the first OMAC off pulsing, with stricter performance parameters near the station. Tests include six-degrees-of-freedom maneuvers and dedicated hot fires on the way to the station, and more stress tests after undocking, using up the propellant. A higher-frequency data recorder will be added.

Crewed flights and Vulcan

Starliner 2 will begin a series of as many as five crewed missions under the current plan. Mulholland put readiness at mid-2028. Before it flies, new crew module thrusters, battery upgrades, stronger parachute seams (a parachute joint redesign) and the poppet redesign will be installed. Hoburg, pilot of SpaceX Crew-6 with over 185 days aboard the station and two spacewalks, said the backup control layer was not exercised on CFT and he hopes to complete that objective.

Weigel said six Atlas rockets remain and NASA intends to use all of them, but their limited-life components add risk. NASA will work with Boeing and United Launch Alliance to certify Vulcan Centaur for Starliner, using the version with two solids and the 85K upper stage, with a new launch vehicle adapter and wind tunnel tests. Isaacman gave the value of the upgrades plus Vulcan certification as $359 million; missions five and six kept their prior pricing and are not yet authorized.

On Dragon, Weigel said NASA had just bought three additional missions, bringing Dragon to Crew 17. Isaacman said forecast demand is about one crew mission every six months.