Crew Dragon's main competitor in the field of manned space flights is systematically unlucky. The CST-100 Starliner project is developing much slower than SpaceX's brainchild. The next test flight, this time manned, is scheduled for April 2023. Representatives of NASA and Boeing reported on the degree of readiness of the ship for the most important test before the start of full operation.
According to the SpaceNews portal, as of February 17, the pre-launch preparation of the ship is 80 percent complete. The next most important step — refueling the service module with fuel — will begin in the first half of March. The launch of the CST-100 Starliner on an Atlas V rocket is scheduled for mid- or late April. This will be the last test flight of the spacecraft, during which it must confirm its readiness for permanent use as a means of delivering people and cargo to orbit and then back.
The Boe-CFT mission will last eight days, of which six will be docked to the International Space Station (ISS). Theoretically, if the flight goes without problems, the crew of the Starliner and all the equipment should be able to spend up to six months as part of the ISS. And also be ready to take the third astronaut on board. This "safety margin" has been added to the mission requirements in advance, but has become especially relevant in light of recent problems with Russian ships in orbit.
Recall that the testing of the CST-100 Starliner encountered a whole series of troubles. In the first test unmanned flight (OFT-1, December 2019), incorrect operation of the on-board computer led to fuel overspending after launching into orbit. Because of this, the ship could not dock to the ISS and fulfill the key tasks of the mission. The second attempt (OFT-2, May 2021) was more successful and is considered successful, but its start was postponed several times. At first, there were problems with the software again and it took several months to fix them. At the same time, the launch window of the "Starliner" for OFT-2 shifted and began to conflict with the schedule of other ships docked to the ISS. As a result, it was still shifted, and while they were waiting for the opportunity to take off, it turned out that there were comments on the fuel system of the service module.
The fact is that the ship spent a long time in a refueled state, and this helped to identify an unforeseen problem. Normally, a small part of the fuel components can leak behind the valves. Usually this does not cause any difficulties, but the CST-100 Starliner had condensate in the purge pipelines, which reacted with fuel and oxidizer - and corrosion of the tubes and shut—off valves themselves occurred. It turned out to be not so easy to solve the problem: either completely redesign the ship to prevent it in the future, or change the refueling procedures. For the first manned flights, the second option was chosen.
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| The launch of the Atlas V rocket with the Boeing CST-100 Starliner in May 2022 (the second unmanned test flight). Interestingly, for Atlas, the Boe-CFT mission will be one of the last launches, the carrier goes down in history. But at the same time — the first manned launch of this rocket [. |
| Source: Reuters, Steve Nesius |
Now the Starliner service module should not spend more than 60 days in the refueled state, which is why they plan to fill fuel with an oxidizer no earlier than March. And the design changes will appear only in the equipment for the second operational flight.
There is another factor limiting the Boe-CFT launch window. Only two docking nodes are available on the ISS for American spacecraft. The first will be occupied by the SpaceX Crew Dragon of the Crew-6 mission, which is scheduled to arrive at the station on February 27, and will remain there for the duration of the expedition. By the fifth of March, the Crew-5 mission ship will be detached from the second docking adapter, and the CRS-27 cargo Dragon will take its place on the 12th. He will stay in the state connected to the station for at least a month. That is, the place will be vacated no earlier than April 12. And already in May, the second private Crew Dragon mission to the ISS is planned — Axiom-2. In other words, the schedule is incredibly tight, if the launch of the "Starliner" is delayed, he risks again "going to the right" for many months.
The test pilots in the flight of the Boe-CFT will be experienced astronauts, as well as for the manned "Dragon" at the time. The seats in the capsule will be occupied by Butch Wilmore (Barry Eugene Wilmore) and Sunita Williams (Sunita Lyn Williams). The first one has two flights, 178 days in orbit and more than 25 hours in outer space. Sunita, in turn, also flew twice, but spent 321 days in orbit, and 50 hours and 40 minutes in outer space. She held the record for the total time and number of spacewalks for a woman.
Both crew members, in addition to their careers as astronauts, were test pilots of the US Navy. In addition, for both Butch and Sunita, the CST-100 Starliner will be the third type of spacecraft they will control. Before that, they had once flown on Shuttles and Soyuz each. A curious fact: in 2007, Sunita worked with Michael Lopez-Alegria during the STS-117 mission, and after working at NASA, he moved to Axiom Space and became the commander of the first completely private spacecraft mission.
