Boeing said Monday it had qualified software for the company’s Starliner crew capsule after programming errors cut short the spacecraft’s first orbital test flight in 2019, and Kennedy Space Center technicians connected the crew and service modules for the next non-flying Starliner. test flight. to the International Space Station in March.
NASA and Boeing officials officially aimed for the second Starliner Orbital flight test on March 29, a repeat of the first test flight in 2019, when software problems prevented the capsule from connecting to the space station. Boeing and NASA executives agreed last year to fly the OFT mission again to demonstrate an entire flight series of Starliner before clearing the spacecraft to fly astronauts.
The Starliner landed safely in New Mexico, but engineers began a revision of all of the spacecraft’s software code to prevent a recurrence of the problems during the first OFT mission.
Several NASA and industry officials said the launch of the OFT-2 mission could be postponed until about March 25. Boeing’s Starliner missions take off on the United Launch Alliance Atlas 5 rockets from the Cape Canaveral Space Force Station, and the capsule ends up under parachutes at one of several sites in the western United States.
The OFT-2 mission will lay the groundwork for the next Starliner test flight to transport three NASA astronauts to the space station later this year, followed by the start of regular rotational flights.
Boeing said Monday that engineers have completed a “complete review” of the Starliner flight software. Teams also evaluated the process for customizing and upgrading the software in the future.
“The work this team has done to completely wipe out our software is a defining moment for the program,” John Vollmer, Starliner vice president and program manager, said in a statement. “We’re smarter than a team that went through this process, and most importantly, we’re smarter than a human space community.”
Meanwhile, a Boeing spokesman said technicians in the Commercial Crew and Cargo Processing Facility at NASA’s Kennedy Space Center paired the crew and service modules last week for the OFT-2 mission, a key milestone in preparing the spacecraft for the launch.
Assuming the OFT-2 mission takes place around March 25 with a launch date, Boeing crews will load the Starliner next month with hypergolic propellant before transporting the capsule to the Atlas 5 launch site.
One change in the hardware for the OFT-2 mission is the installation of a new hood system cover on the nose of the Starliner crew module. The door is designed to better protect the sensitive components of the docking port during the heat of re-entry, and will help reuse the Starliner crew modules at least ten times, according to the spacecraft’s design specifications, officials said.
The door will open as soon as it reaches the Starliner orbit, allowing the interface of the craft to connect to the space station. After disconnection, the door closes for re-access. The lid is similar to the nose shield door on SpaceX’s Crew Dragon spacecraft.
Boeing plans to switch between two reusable crew modules for all planned Starliner missions. Each flight will use a new service module that provides the propulsion and power generation for the spacecraft. The crew module of the OFT-1 mission is being upgraded for Boeing’s Crew Test Flight, the first Starliner mission with astronauts.
In 2014, NASA awarded contracts to Boeing and SpaceX to develop the spacecraft Starliner and Crew Dragon to transport astronauts to and from the space station. Both programs experienced technical delays, but last year SpaceX successfully launched its first two crew missions – a test flight and its first operational rotation mission – bringing human spaceflight to the United States for the first time since the end of spaceflight. States have recovered. shuttle program in 2011.
The commencement of operational flights with Boeing’s Starliner will give the United States two independent spacecraft designs that can carry crews for the first time in the history of the low – Earth space program.
Boeing said the software reclassification milestone provides the basis for an end-to-end simulation of the OFT-2 test flight at the company Avionics and Software Integration Lab in Houston. The end-to-end simulation will “use flight hardware and the final versions of Starliner’s flight software to accurately model the spacecraft’s expected behavior,” Boeing said.
The simulation will take a few days, according to Boeing, the software functionality from pre-launch to docking and the decoupling to landing.
The end-to-end exercise was not performed to verify the software code prior to the OFT-1 mission. An independent NASA Boeing review team has issued 80 recommendations aimed at providing more thorough software testing, process improvements and some hardware changes.
Investigators also recommended that NASA officials improve their oversight of Boeing’s Starliner team.
The software retraining effort involved setting up the Starliner simulators and emulators properly to mimic the actual operation of the spacecraft during flight. Engineers reviewed and updated the spacecraft’s software code and completed tests in the software integration lab.
Boeing said the test “includes hundreds of cases, ranging from single mission verifications to comprehensive end-to-end mission scenarios with the core software.”
United Launch Alliance, the launcher of Starliner, and NASA are involved in testing the software to ensure proper integration while the spacecraft is climbing into orbit, and boarding and disembarking at the space station.
“As we pursue these critical milestones and reviews, we remain true to our values of safety, quality and integrity,” Vollmer said. “The completion of OFT-2 brings us one step closer to our ultimate goal of transporting astronauts to and from the International Space Station this year.”
The software bugs discovered during the OFT-1 mission in December included an evolution of the Starliner mission time clock that was set incorrectly before launch. The problem caused the spacecraft’s computer to think it was in a different flight phase after being launched from the Atlas 5 rocket into orbit, causing the fire extinguishers to encapsulate and burn too much propellant. .
The higher-than-expected fuel consumption prevented the Starliner spacecraft from continuing at the International Space Station.
Ground crews discovered another software coding error that could have caused the spacecraft’s service module to collide with the crew module after the two elements were separated just before entry. During certain parts of the shortened two-day mission, there were also problems in establishing a stable communication link between the Starliner spacecraft and NASA’s network of tracking and data redirection satellites.
The OFT-2 mission is expected to last approximately one to two weeks.
Phil McAlister, NASA’s director of commercial spaceflight, said last week that SpaceX’s next Crew Dragon mission – with four astronauts – would begin in March or April, about the same time as the Starliner OFT-2 test flight.
The space station has two landing ports to receive commercial crew capsules, but the next Crew Dragon flight – known as Crew-2 – will arrive at the complex before the current Crew Dragon mission departs.
This means that the OFT-2 test flight cannot start during the handover between the Crew-1 and Crew-2 missions.
“We will disrupt the missions as we get a little closer, depending on the readiness of the spacecraft and the needs of the ISS,” McAlister said on January 13 during a meeting of the NASA Advisory Board’s Human Investigation and Operations. committee.
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