Boeing's Starliner launches on 3rd attempt to reach International Space Station

[Buster's Uncle]

Boeing's Starliner launches on third attempt to reach International Space Station
Denise Chow
Thu, May 19, 2022, 7:18 PM
NBC News


Aerospace giant Boeing launched its Starliner space capsule Thursday to the International Space Station in a crucial test of its ability to safely fly to the orbiting outpost.

The much-delayed flight was Boeing's third attempt to complete an uncrewed trip to and from the space station, after the company was sidelined by software glitches and issues with the spacecraft's fuel valves. The test flight is part of Boeing's contract with NASA and represents an important step in certifying the capsule to eventually carry astronauts into space.

The Starliner capsule lifted off Thursday from the Cape Canaveral Space Force Station in Florida at 6:54 p.m. ET. The gumdrop-shaped spacecraft launched atop an Atlas V rocket and is expected to autonomously dock with the space station Friday evening.



Boeing's Starliner space capsule is designed to one day carry astronauts to and from the International Space Station. (Boeing)


While there are no human passengers on board, the stakes are high for Boeing. The company has fallen significantly behind its competitor SpaceX, which is similarly under contract with NASA to ferry astronauts to the International Space Station.

SpaceX completed an unpiloted test flight of its own Crew Dragon spacecraft in 2019 and successfully flew two astronauts to the space station the following year. Since then, the company has carried out five fully operational flights to the orbiting lab.

Software problems prevented the Starliner capsule from attempting to dock at the space station during an initial test flight in 2019. Fuel valve issues discovered last summer thwarted a second attempt and caused an additional nine months of delays.

Now, both Boeing and NASA say the problems have been fixed and they are ready to fly.

"We wouldn't be here right now if we weren't confident that this would be a successful mission," Butch Wilmore, a NASA astronaut who is slated to eventually fly on the Starliner's first crewed mission, said Wednesday in a news briefing.

The flight, known as Orbital Flight Test-2 or OFT-2, requires the spacecraft to autonomously rendezvous and dock to the International Space Station. The capsule will then spend around five days attached to the orbiting outpost before returning to Earth. Unlike SpaceX's Crew Dragon craft, which was built to splash down in the ocean, the Starliner capsule is designed to land under parachutes at White Sands Missile Range in New Mexico.

The Starliner spacecraft is carrying more than 800 pounds of cargo to the space station, including a mannequin nicknamed "Rosie the Rocketeer" in one of the capsule's seats. The dummy astronaut is equipped with 15 sensors that will collect data throughout the flight, according to NASA.

Both Boeing's Starliner capsule and SpaceX's Crew Dragon were developed under NASA's Commercial Crew Program, which was set up to help fund the creation of alternative ways to reach low-Earth orbit after the space agency retired its space shuttle fleet in 2011. NASA awarded Boeing $4.2 billion in 2014 as part of the program, and SpaceX received $2.6 billion that same year.


https://www.yahoo.com/news/boeing-making-third-attempt-reaching-183349021.html

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Isn't the valve problem on the Atlas V booster and not on the Starliner capsule?

[Unorthodox]

Boeing's Starliner launches on third attempt to reach International Space Station


Isn't the valve problem on the Atlas V booster and not on the Starliner capsule?

I haven't dug into how it stacks or fuels.  But, given the delay, I'd think the valve was either on the module or at the separation junction between module and Booster.  Wouldn't shock me to see some LOX and a tiny engine on the module itself.  There's a couple other fuel possibilities but I can see the advantages to one fuel on the whole system approach. 

[Unorthodox]

https://spaceflightnow.com/2021/08/19/boeings-starliner-spacecraft-returns-to-processing-facility-for-valve-work/

The Starliner’s service module has 28 reaction control system thrusters, each generating about 85 pounds of thrust. The service module has 20 more powerful orbital maneuvering and attitude control thrusters providing 1,500 pounds of thrust. There are four large launch abort engines at the base fo the spacecraft, each with 40,000 pounds of thrust. Those would only be activated in the event of an emergency during launch.

There are 12 control thrusters on the reusable Starliner crew module. The service module is disposable and used only once.

The service module thrusters are all fed by hydrazine fuel and nitrogen tetroxide oxidizer. When the liquids make contact, they automatically ignite.

Boeing said the service module has 24 fuel valves and 24 oxidizer valves to control the flow of propellant to the thrusters. There are an additional 16 valves in helium lines used to pressurize the propulsion system.

All 13 troublesome valves are associated with the oxidizer system. After inspections and troubleshooting inside the VIF, Boeing technicians got nine of the valves to move into the correct positions.

John Vollmer, manager of Boeing’s Starliner program, said last week that engineers believe atmospheric moisture made its way into the service module. The moisture apparently reacted with the nitrogen tetroxide to create nitric acid, which corroded the valves and caused them to stick, Vollmer said.

Boeing said it was too early to know whether the valves might need to be redesigned, or whether ground teams could take more steps to ensure moisture does not get into the valves.

So...they still haven't fixed the problem, and might have to scrap the [poop] all together and redesign:

https://www.cnbc.com/2022/05/12/boeing-considers-redesigning-crucial-valve-for-starliner-space-capsule.html