Stranded in orbit: The return of the two test astronauts of the Boeing Starliner capsule is further delayed – they may even have to stay on the International Space Station ISS until 2025. Because there is still no authorization for a manned return flight with the defective Starliner capsule. NASA did not rule out the possibility that the capsule will be recovered without a pilot at a press conference on Wednesday, August 7. But this also disrupts the schedule of the ISS crews.
The test flight of NASA astronauts Sunita Williams and Barry Wilmore was actually scheduled to take place it only lasts eight days. Your job: Fly Boeing’s Starliner space capsule to the ISS and back. But nothing was done: After helium leaks and engine failures occurred on the outbound flight on June 6, 2024, the two astronauts stayed for safety reasons. initially on the ISSSince then, NASA and Boeing have conducted countless tests to clarify the technical issues.
Problems with Teflon Seals
But it now appears that there is still no safe option for the return of the two astronauts. As NASA announced in a press conference on Wednesday, August 7, 2024, ground tests with identical propulsion nozzles revealed overheating problems. The heat caused the Teflon seals to swell and restricted fuel flow. Although the space capsule’s propulsion nozzles currently appear intact, it is unclear whether the problems will recur with prolonged use.
Therefore, it cannot yet be guaranteed that the return of the Starliner will not result in further engine failures, which are necessary for a controlled re-entry into the atmosphere. “This uncertainty around the thrusters is causing more and more unease within NASA,” said Steve Stich, manager of NASA’s Commercial Crew Program.
Six months instead of eight days?
What now? If a safe return flight cannot be guaranteed by mid-August, Williams and Wilmore will, in extreme cases, have to stay aboard the International Space Station until February 2025, another six months, as NASA has announced. The Starliner would then have to be returned to Earth unmanned and the two astronauts would have to wait for the next opportunity to return with a Dragon space capsule from Space X. However, this could only happen as part of a normal crew rotation.
“We haven’t decided on that plan yet,” Stich says. But preparations have already been made for that eventuality. Spacesuits have already been selected for the two astronauts, which they would need for their return in a Dragon capsule. They would then have to be launched into orbit when the ISS crew change is imminent. Instead of the planned four astronauts, only two astronauts would fly in order to free up space for Williams and Wilmore when they return. They would then have to take over the duties of the two crew members who remained on the ground for the next six months.
Schedule conflicts with other space missions
But the problems with the Boeing space capsule aren’t just affecting the two astronauts Williams and Wilmore who are still stuck on the ISS: the regular ISS crew is also affected. Their replacement was due to fly to the space station aboard a SpaceX Dragon capsule in early August. This crew change has now been postponed by more than a month, to September 24, 2024. “This adjustment gives mission managers more time to finalize the return flight of the Starliner space capsule currently docked at the space laboratory,” NASA said.
But the postponement brings other problems: Crew-9’s new launch date must be coordinated with the launch of a Soyuz capsule to the ISS, also scheduled for mid-September. And there are also time constraints on the ground: “Teams are working to prepare for the launch of the Crew 9 mission at Cape Canaveral so that it does not disrupt launch pad preparations for NASA’s Europa Clipper mission,” NASA says. Europe Mower is an unmanned space probe designed to explore Jupiter’s moon Europa and its subglacial ocean.
An unmanned resupply flight to the ISS using a SpaceX space capsule must now be postponed until October due to the postponement of the Crew 9 mission.
Decision by mid-August
As NASA points out, the final decision has not yet been made; it is expected to come no later than mid-August. “Our plans could still change dramatically in one direction or another based on what new data reveals,” said Ken Bowersox of NASA’s Space Operations Directorate. Field tests are currently still underway with identical training nozzles.
“Abandoning our original plan to bring Butch and Suni back on the Starliner will create additional risks to the rest of our mission profile — and we have to weigh all of those risks,” Bowersox said. However, he also acknowledged that the likelihood of the Starliner returning unmanned has increased based on data from the past two weeks. “But new data continues to come in — everything could still change,” Bowersox said.
Source: NASA
August 8, 2024 – Nadja Podbregar