Boeing has been evaluating a new target launch date for its next Starliner mission over the last several weeks. The next test flight for the Starliner capsule won’t have crew aboard. The mission will launch aboard an Atlas V rocket and dock with the ISS, spending about a week on the orbiting space station before returning to Earth. This test flight is expected to happen in July or early August, but no official date has been announced.
NASA has said that the vehicle is close to being ready, with only a few tests left to certify the spacecraft for flight. One of the most significant challenges in naming a date for the next Starliner flight is finding a docking port aboard the ISS. Currently, the ISS has two ports that support the SpaceX and Boeing Starliner capsules. Priority access to these ports is guaranteed to resupply missions most often handled by SpaceX.
That means a big challenge for Starliner is to find an available docking port as the Crew Dragon expected to launch on April 22 will be attached to one of those docking ports for about six months. On June 3, SpaceX has a cargo supply mission due to launch and occupy the other port. That means there will be no docking ports available for Boeing to use until around July 20, when the CRS-22 Dragon resupply mission will depart the space station and return to Earth.
When the Dragon resupply capsule departs the space station, there will be about a one-month window to launch Starliner and dock with the ISS. That seemingly can’t happen until late July or early August. Starliner could spend about a week at the station before returning to Earth as another Dragon supply mission will arrive at the ISS in late August.
This would mean that the first Starliner mission with crew aboard will likely not happen until January 2022. NASA has stressed that a crewed mission with Starliner won’t occur until the spacecraft is ready and will happen based on the space station’s needs. However, NASA does hope that a 2021 launch date may be found for the mission.