The long-awaited manned launch of Starliner has gained increasing positivity that its latest launch date will remain correct, after several slip-ups since the first uncrewed flight to the International Space Station (ISS).
Although NASA has postponed the NET launch date for the Starliner Crew Flight Test (CFT) it is now set for April 14, 2024 due to scheduling reasons, the NASA Aerospace Safety Advisory Panel (ASAP) – a traditionally conservative body by nature – cited hope that Boeing’s latest problems with the spacecraft are coming to an end for launch in April. This was followed by the NASA Advisory Council (NAC) citing the specific launch date.
Starliner has completed two uncrewed flight tests, the first being the infamous mission in December 2019 that revealed several software issues and failed to reach the International Space Station (ISS).
The second was Orbital Flight Test-2, which docked at the Station on May 21, 2022, after a launch two days before Kennedy.
The spacecraft remained docked to the ISS for four days before successfully landing at the White Sands Missile Range in New Mexico, this time with only more minor problems, such as problems with reserve thrusters during the flight.
During a previous meeting in May, the panel was somewhat critical of Starliner’s progress and warned against launching too early to avoid potential safety issues. This was a few days before Boeing and NASA had to admit flammability problems with some tape used inside the capsule and safety concerns with the parachutes.
Now, ASAP members are much more optimistic about the launch path after months of work to mitigate the latest issues.
“ASAP believes it is important to have two crew providers and is pleased with the progress,” said Kent Rominger, a former space shuttle astronaut with five flights under his belt, two as commander. “Boeing has responded; tape removal on the upper dome is complete, while work on the lower dome should be completed in a few weeks. The parachute’s flexible joints are being redesigned and a drop test is imminent.
“NASA and Boeing are working on the battery redesign plan, and the CFT batteries have been approved for flight. ASAP was pleased to see the independent reviews.”
This positive assessment of a number, as Rominger noted, has a lot of value. He was the head of NASA’s Astronaut Office during the Columbia tragedy in 2003. He belongs to a generation at NASA that has the importance of a proper safety culture and the dire consequences of a lack thereof ingrained in its DNA.
ASAP cited that the NET date for CFT is around April 2024, with Boeing still targeting March to have everything checked, verified, approved and ready on the technical side. Other factors are at play, such as scheduling the ISS Visiting Vehicle (VV) to find a reserved space for the Starliner to dock at the orbital outpost. However, NAC provided an update with a specific NET date of April 14th.
The latest editions release includes the P-213 tape referenced in the last update.
Problems with the flammability of the P-213 tape used on the Starliner caught Boeing and NASA by surprise. The tape is wrapped around electrical harnesses to protect them from possible abrasions or cuts – and is widely used in other spacecraft, including the ISS.
However, it is flammable under specific conditions that may arise after another onboard failure occurs – a fact discovered in extensive testing in preparation for the CFT’s launch.
“This is a tape widely used in the aerospace industry for many wire protection applications against abrasion. I would say that in the NASA database the entries were a little inconsistent regarding the flammability of that tape at various oxygen concentration levels. And so, it was a little confusing knowing when it could be used and when it couldn’t,” NASA’s Commercial Crew Program manager said at a press conference in August.
As Rominger stated on ASAP, the removal of the tape on the bottom of the spacecraft is still underway at KSC, but should be completed in the next few weeks. Any tape remaining in some hard-to-reach locations or deemed non-critical will undergo a final assessment to ensure an acceptable level of risk.
Another issue to be clarified related to parachutes, with the newly designed drogue and main parachute soft attachment joints and stronger main canopy suspension lines will be installed on the CFT spacecraft by the end of the year, with a drop test now planned for early 2024. Initially, this test was scheduled for “late November 2023 at the earliest.”
Boeing is also working on a radiator bypass valve issue discovered during ground operations. To prevent this from happening again, the hardware has been modified. Future options to further improve the system are considered, including cleaning the system to prevent friction, component upgrades, and changes to the way the system operates.
Once all of these issues are approved and cleared for flight, astronauts Butch Wilmore and Suni Williams will be tasked with carrying out the spacecraft’s first manned mission.
They continue to train for their mission by going through simulations of all phases of flight together with Mission Control at Johnson Space Center (JSC) and other support teams. At the same time, the requirements regarding the manual control of the spacecraft crew and the analysis of the abort system, which are essential for its safety, have been achieved and will soon be finally closed.
On the software side, CFT flight software qualification tests are completed. Hardware and software integration testing is still ongoing at Boeing.
On the pure hardware side, the Starliner crew and service module are already coupled with normal pre-flight processing.
The ULA Atlas V rocket is already at Cape Canaveral Space Force Station, and the spacecraft integration process is expected to begin shortly after a successful drop test.
Main photo: Inside the Boeing commercial crew and cargo processing facility at NASA’s Kennedy Space Center in Florida. Photo credit: Boeing/John Grant