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Cape Canaveral ground crews brought Boeing’s Starliner crew capsule and a United Launch Alliance Atlas 5 rocket inside their assembly hangar on Thursday for further troubleshooting of the misbehaving valves inside. of the Starliner propulsion system.
Without a quick fix, technicians will have to remove the spacecraft from the Atlas 5 rocket for more in-depth work, potentially delaying the unmanned Starliner Orbital Flight Test-2 mission to the International Space Station by several months.
The ULA has already taken steps to guard against the possibility that the Starliner’s Atlas 5 rocket may need to be disassembled to allow the company to move on to other missions on its launch schedule. Before returning the Atlas 5 to the hangar, ULA drained the first stage fuel tank of kerosene.
Standing on a mobile launch pad, the 172-foot-high (52.4-meter) rocket left its launch pad on pad 41 at the Cape Canaveral space station and returned to the integration facility. ULA vertical late Thursday morning.
With the return of the Atlas 5 and Starliner to the VIF, workers planned to install access platforms and begin another round of troubleshooting in an effort to find the reason for the propulsion valves at the interior of the spacecraft appear to be in unexpected positions.
The valve problem prompted Boeing to order a scrub during an attempted launch on Tuesday. Additional checks have ruled out a number of potential causes, including software, Boeing said.
Engineers noticed that the valves behaved poorly after a thunderstorm that passed over the launch pad on Monday. Boeing said extreme weather conditions appear to be an unlikely cause of the problem, but teams inside the VIF will inspect the spacecraft’s “doghouse” propulsion pods for water or electrical damage.
But not all niches are accessible in the VIF, and the commands to activate the valves while the spacecraft was on the launch pad gave no change in the position indications.
The valves for the propulsion system in question are inside the Starliner’s service module, which has a set of rocket thrusters designed to propel the spacecraft away from its launcher during an in-flight emergency. Other thrusters on the service module are used for in-orbit maneuvers and aiming control of spacecraft.
Boeing said in a statement that one of the first steps after the spacecraft returns to the VIF was to power up the Starliner capsule, which takes several hours. Then the engineers will send out commands to operate the valves. If that doesn’t work, teams could try to control the valves using different methods.
“We let data guide our decision-making and we won’t fly until our integrated teams are comfortable and confident,” said John Vollmer, vice president and program director of the Commercial Crew Program at Boeing.
The next launch opportunities for the Starliner mission are Saturday and Sunday, but Starliner inspections and tests are unlikely to be completed – and any potential issues on the service module resolved – in time for a weekend launch. -end, sources said.
If the valve problem persists, Boeing should detach the Starliner capsule from the top of the Atlas 5 rocket and return it to the company’s spacecraft factory at the nearby Kennedy Space Center.
This would put the OFT-2 mission’s launch schedule in competition with several other important NASA missions over the next two months.
A SpaceX Cargo Dragon capsule is scheduled for launch on August 28, and it will use the same docking port that the Starliner spacecraft needs. The Dragon spacecraft will occupy the space station docking port until the end of September.
NASA’s Lucy science probe on asteroids is scheduled to take off during a 23-day planetary launch period that opens on October 16. Like the Starliner mission, Lucy will use a United Launch Alliance Atlas 5 rocket to leave Earth and head to the Solar System for encounters with eight asteroids, a record number for a single mission.
Lucy can only launch when Earth is in the correct position in its orbit around the sun, relative to its asteroid targets. The robotic mission has a back-up launch period in October 2022, but the spacecraft has already been shipped from its Lockheed Martin, Colo. Plant to Cape Canaveral to begin final preparations for the launch.
Another Atlas 5 launch was to take off in early September with experimental satellites for the US Army’s space testing program. This mission, designated STP-3, may have to be postponed after Lucy’s launch due to delays in launching the OFT-2 mission from the Starliner.
If it seems likely that the Starliner valve issue will take more than a few weeks to resolve, the ULA should take the Atlas 5 launcher apart and start stacking the next Atlas 5 rocket for launch from Cape Canaveral. With little time to adjust to the STP-3 mission, it will likely be the Atlas 5 rocket for Lucy’s launch.
The ULA also has an Atlas 5 rocket that will be launched on September 16 from the Vandenberg Space Force base in California with NASA’s Landsat 9 terrestrial imagery satellite and the US Geological Survey. The company needs about a week between Atlas 5 launches from Vandenberg and Cape Canaveral. If the launch of Landsat 9 remains set for September 16, this would prevent the launch of any Atlas 5 mission from Florida for a few weeks in mid-September.
Once the OFT-2 mission is cleared for take-off, the Starliner spacecraft will dock with the space station, where the lab crew will open the hatches leading to the crew’s capsule. Station crew members will unload several hundred pounds of cargo and inspect the capsule’s crew cabin.
A test dummy named “Rosie the Rocketeer” will occupy one of the capsule seats on OFT-2.
The Starliner Crew Pod is embarking on a redesign of the struggling 2019 OFT-1 demo mission that failed to reach the space station. Boeing and NASA blamed the botched mission on software programming errors, and officials say additional testing fixed the software issues ahead of this mission.
Boeing developed the CST-100 Starliner spacecraft under contract with NASA, which has similar agreements with SpaceX for that company’s Crew Dragon program. SpaceX’s capsule began carrying astronauts to the space station last year, and Boeing is now over a year behind schedule.
The two companies have contracts with NASA for at least six crew trade missions to space stations. SpaceX has already launched two of its operational crew rotation flights.
Before Boeing can move on to its first crewed test flight, NASA officials want to make sure the contractor fixed the software issues that cut short the 2019 test flight. Starliner will also prove the spacecraft’s rendezvous and docking systems, which were not used during the 2019 mission.
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