The Boeing Starliner Orbital Flight Test (also known as Boe-OFT) was the first orbital mission of the CST-100 Starliner spacecraft, conducted by Boeing as part of NASA's Commercial Crew Program. The mission was planned to be an eight-day test flight of the spacecraft, involving a rendezvous and docking with the International Space Station (ISS), and a landing in the western United States. The mission was launched on 20 December 2019 at 11:36:43 UTC or 06:36:43 AM EST; however an issue with the spacecraft's Mission Elapsed Time (MET) clock occurred 31 minutes into flight. This anomaly caused the spacecraft to burn into an incorrect orbit, preventing a rendezvous with the International Space Station (ISS). The mission was reduced to just two days, with the spacecraft successfully landing at White Sands Space Harbor on 22 December 2019.

On 6 April 2020, Boeing announced that it would conduct another Orbital Flight Test to prove and meet all of the test objectives. NASA accepted the proposal from Boeing to do another uncrewed test flight, Boeing Orbital Flight Test 2.

Boeing Orbital Flight Test

Payload

Instead of carrying astronauts, the flight carried an Anthropomorphic Test Device (ATD) wearing Boeing's custom flight suit. The ATD is named Rosie (aka "Rosie the Rocketeer"), as a homage to all the women who helped contribute to the Starliner Program. The capsule was weighted similarly to missions with astronauts onboard and carried approximately of supplies and equipment including a plush toy of Snoopy and holiday presents for the Expedition 61 crew members. Due to the inability to dock with the ISS, this cargo was never delivered.

Boeing Orbital Flight Test

Mission

The first Atlas V N22, designated AV-080, launched the CST-100 Starliner spacecraft on an uncrewed test flight to the International Space Station. The capsule was intended to dock with the space station, then return to Earth to land in the Western United States after an orbital shakedown cruise ahead of Boeing Crewed Flight Test.

Boeing Orbital Flight Test

OFT is the first flight of an Atlas V without a payload fairing and its first flight with a dual-engine Centaur upper stage. The dual-engine Centaur utilizes two RL-10 and is required for Starliner flights in order to provide a launch trajectory that allows for a safe abort at any point in the mission.

The mission launched successfully on 20 December 2019 at 11:36:43 UTC, but thirty-one minutes after launch the mission elapsed timer (MET) clock made an error. During a later press conference, it was revealed that MET was offset by 11 hours. When it became obvious that the maneuver did not happen, NASA and Boeing tried sending commands to get Starliner back on track, but the position of the spacecraft switching communications between two TDRS satellites delayed the orbital insertion burn. This delay resulted in an abnormal orbit and excessive fuel use. The decision was made to scratch the ISS rendezvous/docking since the spacecraft burned too much fuel to reach orbit even after Mission control center fixed the MET clock issue. NASA and Boeing officials placed the spacecraft in a different orbit and the entire flight plan had to be redone and the mission was reduced from eight days to three flight days.

By 11:40 UTC, the Starliner was in a "stable orbit", though orbital insertion was not nominal. It was later confirmed that Starliner had placed itself into a 187 x 222 km orbit.

By 13:55 UTC, mission control center had realized that docking with the ISS was precluded. Despite not being able to dock and the MET anomaly, Jim Bridenstine stated during a press conference that "A lot of things went right. And this is in fact why we test".

On 22 December 2019, Starliner was cleared to reenter the Earth's atmosphere. After deorbiting, Starliner reentered the Earth's atmosphere, before successfully deploying all sets of parachutes. Starliner deployed airbags and successfully touched-down at White Sands Space Harbor at 12:58:53 UTC. Though the ISS rendezvous that was planned for the OFT did not happen, Jim Chilton, vice president for Boeing's space and launch division, estimated that Starliner has achieved over 60% of the flight objectives, and this could reach over 85% once all the data from the spacecraft is retrieved and analyzed.

The spacecraft will later be reused on mission Boeing Starliner-1. Its commander, Sunita Williams, informally dubbed the spacecraft "Calypso" after the famed oceanographic research ship and its eponymous John Denver song.