Boeing’s Starliner crew capsule successfully encountered, approached and docked with the International Space Station for the first time, marking several major milestones for NASA and its second partner Commercial Crew.
Starliner’s second orbital flight test (OFT-2) began on schedule with a near-perfect launch May 19 on a United Launch Alliance (ULA) Atlas V rocket. As thousands of employees and stakeholders held their collective breath, the uncrewed prototype safely detached from Atlas V’s Centaur upper stage and propelled itself the rest of the parking orbit. steady. Two and a half years after their first attempt, Boeing and NASA were finally able to send Starliner en route to the International Space Station (ISS) and prepare for near operations.
— Samantha Cristoforetti (@AstroSamantha) May 21, 2022
As previously reported on Teslarati, Starliner flying through the first hour without experiencing a catastrophic issue was already a milestone for Boeing and a massive improvement over the company’s last two orbital flight test attempts.
“The story of Starliner’s Tortured Orbital Flight Test (OFT) campaign began in earnest on December 20, 2019, when an uncrewed prototype first attempted to launch to the International Space Station (ISS) atop a United Launch Alliance (ULA) Atlas V rocket A major software bug that could have been easily detected even with the most basic pre-launch testing of the hardware in the loop has sent Starliner spinning out of control the moment it separated from Atlas V. After hundreds of seconds of unplanned burns of its many thruster attitude controls, Boeing finally regained control but Starliner had run out of propellant to reach the ISS safely.
Boeing would detect and later fix another unrelated software bug just hours before Starliner’s scheduled reentry and recovery which, if undetected, could have crashed the capsule and service sections of the spacecraft. space shortly after separation.
On July 30, 2021, shortly before another uncrewed Starliner was scheduled to reattempt the first orbital flight test, the launch was aborted. Boeing and NASA later reported that 13 of Starliner’s 24 main oxidizer valves failed to open during a pre-launch test just hours before liftoff. It was ultimately concluded that faulty valves supplied by Aerojet Rocketdyne and poor integration by Boeing allowed water intrusion and extensive corrosion. As a result, the next attempt to launch OFT-2 was delayed by almost ten months.
Instead of a calamity, Starliner’s second and third OFT attempts were mostly met with success. After reaching orbit, the spacecraft began to raise and “phase” its orbit to rejoin the ISS and performed all required burns and navigation without major problems. Finally, after several intentional test maneuvers and approximately an hour of unscheduled troubleshooting, Starliner began its final approach and successfully docked with the ISS – joining a SpaceX Crew Dragon – at 8:28 p.m. EDT May 20 (00:28 UTC May 20). May 21st) .
Starliner’s successful docking made it the fourth, fifth, or sixth U.S. spacecraft to reach the ISS, joining the Space Shuttle, SpaceX’s three main Dragon variants, and Orbital ATK’s Cygnus cargo vehicle (now Northrop Grumman ). It was also the first time that both NASA Commercial Crew Program vehicles had docked simultaneously with the space station — a reassuring sign of a future with redundant access after years of Boeing delays that forced SpaceX to temporarily become the sole source of transportation for NASA astronauts. Although the odds are good that SpaceX will eventually be required to single-handedly maintain NASA access to the ISS for seven six-month (>3 years) “expeditions”, Starliner’s so far successful OFT2 mission improves considerably the chances that the Boeing spacecraft will be fully ready within a year or two.
Nonetheless, Starliner must still safely exit the ISS, lower its orbit, reenter Earth’s atmosphere, and land safely for recovery and reuse. Starliner has already accomplished all of these tasks during OFT1, but tensions will always be high. Additionally, Starliner’s performance during OFT2 is far from perfect. Aside from some minor issues with coolers and radiators, Boeing and NASA revealed that four of the spacecraft’s several dozen thrusters (two larger maneuvering/control thrusters and two smaller attitude control thrusters ) – had run aground at the time it was moored. During OFT1, until 13 thrusters out of order following unplanned burn minutes, but Boeing was able to recover all but one before re-entry.
Technically, that means both missions demonstrated the strong redundancy of Starliner’s propulsion systems, but NASA will no doubt require Boeing to determine likely root causes and qualify fixes before greenlighting the first flight test in crew (CFT) of Starliner. For SpaceX, it took 14 months after Crew Dragon’s near-perfect first uncrewed debut for NASA to agree to conduct a crewed flight test. However, during post-flight testing, the capsule supporting Demo-1 exploded catastrophically, triggering a months-long investigation. The effect of a few failing thrusters is significantly less severe, so Starliner may not have to wait as long for CFT. Hopefully, that means NASA will have two fully redundant astronaut carrier spacecraft available and operational by the end of 2023, if not sooner.
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