Boeing's Starliner launch this evening (May 6), carrying 2 NASA astronauts

Looks to be a long countdown.
The launched has been scrubbed, reportedly due to an issue with the oxygen relief valve on the Atlas V rocket's upper stage.
The rocket boasts a 100 percent success rate over 99 missions.
There are backup launch opportunities on May 7, 10 and 11.
 
After a bunch of yellow caution flags, the space race has two confirmed entries. Meanwhile China is busy prospecting on the dark side of the Moon. China is also working on re-useable rockets.

The Starliner carried about 760 pounds of cargo and 2 astronauts to the space station.

The space X Starship ran a successful test, going up and coming down intact. There was some heat caused damage upon re-entry but otherwise held up pretty good.

The Starliner finally made it to the space station and is expected to stay for 8 days. It took awhile to dock because not all the mini thrusters were working. It has 28 mini thrusters, 5 of them wouldn't work. Manually firing them got 4 out of the 5 working again so they could be used for docking. Apparently they are software controlled and the program was encountering data it didn't like. Adjusting the sensitivity of the software will be done before the next launch. Apparently there were 2 problems with the thrusters, one was not firing up and the other was getting them to fire up.

Can't tell if the starliner rockets were recovered. The booster was supposed to attempt a controlled splashdown in the Gulf of Mexico shortly after liftoff. The Starship upper stage continued into space, looping halfway around the Earth before re-entry and splashdown in the Indian Ocean. I can't find out if they were successful, though I thought I heard something about it not splashing down so good, but can't find any articles. Bad news sinks fast in the oceans of spent data.

4 helium leaks have been discovered on the Spaceliner capsule. It's currently unclear how much helium is leaking or if it will affect Starliner's performance and ability to return to Earth in eight days. Turning the system off stops the helium leaks. Helium is used to pressurize the fuel lines of Starliner's thrusters. There is plenty of spare helium. Basically it seems to be a plumbing problem.

Only the upper section of the capsule returns to Earth, by parachute in the US southwest desert region. The bottom section of the capsule will not return to Earth, which has the malfunctioning thruster jets.
 
@Robert Zwilling thanks for this update. It sounds like not everything is perfect, but that so far the problems are manageable. I don't think this would fill me with confidence for the next trip.
 
I’m curious about the Helium.
Here’s what I’ve found so far:

Helium is used in spacecraft thruster systems to allow the thrusters to fire and is not combustible or toxic,” according to Boeing.

A question for those more in the know. Does that mean that the thrusters actually move the capsule simply by blowing out Helium under pressure? That’s kind of the way I read the statement - that the Helium is used instead of rocket fuel in the thrusters.
 
It's discouraging getting information from the internet. You have keep banging away at it. No one spends much time researching anything they just scoop up enough to make a word count leaving a lot of questions unanswered. I don't even know if they know that they are leaving unanswered questions laying around, maybe they don't care.
I kept asking what is the thruster propellant. Today I finally got half an answer only because yesterday someone at the NY Times also got to wondering about the helium, or wondered what the helium does. It pushes the propellant through the thrusters.

You lose enough helium and the thrusters can't work. Pushing the propellant through the thruster is probably a lot simpler than using pumps but for some reason they are having trouble getting good working seals. The article mentions that Boeing considered the possibility that a series of unfortunate events could stop the thrusters from working which would make it impossible for the capsule to re-enter Earth's atmosphere to land. After much delay it looks like they decided the temporary fix is to just turn off the helium flow off until it is needed. The result was that the helium problem went unresolved. The flight started with 1 leak, which they considered not worth worrying about. 2 more leaks appeared after the flight started, and then after docking a 4th leak was found.

Perhaps Boeing has too much time and money invested in the capsule thruster system and don't want to spend anymore money on the problem. If its not a poor design problem, then maybe helium has different characteristics when it is space or at least in a space/low gravity situation, which would be interesting as I don't think there is any evidence that where an atom is located has any impact on how it behaves physically. Personally I think if the outside environment is different enough from another it could cause atoms to have different characteristics. Extra forces in the emptiness of space could be different from what we experience on Earth. Or its just Boeing being Boeing.

No one has anything that can land people on the Moon and take off due to a variety of practical problems. We can rendezvous and dock with space stations, but the vehicle that will go to the moon and back again may not be a capsule but a mini rocket ship like the Artemis III, Starship Musk is building. That ship's launch dates keep getting moved forward just like Boeing's Space capsule kept getting pushed forward.
 
I should have asked co-pilot about the fuel but I get too many 'time to change the subject responses." Tried it out and got a straight forward answer about the thruster fuel. Co-pilot did get the last say though, as it said "Please note that these propellants are toxic and should be handled with care." As an after thought, it also said please don't eat the rocks.

"The Boeing service module thrusters use a mixture of hydrazine and nitrogen tetroxide as propellant. These thrusters are pressurized using helium, an inert gas. The service module has four doghouse-shaped propulsion pods around its circumference, with lines for hydrazine fuel, nitrogen tetroxide oxidizer, and helium pressurant routed into each thruster pack. This system is used for larger orbital adjustments and launch-abort maneuvers."

Mixing the hydrazine with the nitrogen tetroxide produces combustion without any spark to set it off. Hydrazine is used in a lot of space craft, including satellites, as a fuel capable of being stored for a long time and still be totally functional.

Pressurant means "A gas used to drive a fluid through a fluid system." Pressurized fuel delivery for hydrazine rockets is very common, so not sure why Boeing is having all these problems. Boeing got about twice as much money as Space X to do the same thing. Found some unsubstantiated rumors that have Boeing quitting space travel after this. Boeing built the space Station but that comes down in 2030. The SpaceLiner program is only scheduled through 2030. They have stated that they won't do fixed price space contracts anymore.

Space X uses fixed price contracts but because it is private company it is not known how much it costs to do what it does. One article points out that even though Space X is apparently drastically cutting the costs of launching rockets it is not passing these savings on to its customers. But it is quoting relatively cheap prices to get stuff into space which could be undercutting any other companies in the business of launching space craft. One assumption is that Space X could be operating at a loss to capture the entire space business. Boeing isn't getting any satellite contracts unlike SpaceX which is getting a lot of them, which keeps the SpaceX program running. Robbing Peter to pay Paul?
 
The helium leaks now total 5. They still need to replace the extra water that was used to get to the space station and figure out how it got used. When not in use the helium isn't leaking. The StarLiner space flight from the space station to Earth takes around 7 hours. They have enough material on board to last 70 hours in spaceflight. Swab samples taken outside of the space station will be brought back to Earth to see what kind of microbiomes survive outside the orbiting space station in the vacuum of space.
 
Boeing really aren't having a good time with design and quality control at the moment.
 
I wonder why they used helium? It's the second smallest gas atom, and therefore the second most able to escape from where you want it. I would have thought that nitrogen, nearly twice as big and having the largest non-toxic gas atom, would have been more suitable
 
Pyan said:
I wonder why they used helium? It's the second smallest gas atom, and therefore the second most able to escape from where you want it. I would have thought that nitrogen, nearly twice as big and having the largest non-toxic gas atom, would have been more suitable
Click to expand...
Just looked this up. It could have something to do with the compressibility of the two gasses at low temperatures. Didn't understand it all.
 
Surely the astronauts themselves sabotaged it to get more time on the space station. That's what I'd do...
 
Rocketdyne made the thrusters. They were part of the engine contract. They made engines for the shuttles, which used helium for quite a few things in their operation. The space shuttle engines for the shuttle were reusable, but the main launch Starliner engines and the thrusters were not reusable. They operated the main engines at a higher performance level because they were not going to be used again. Perhaps the thrusters were also designed for one time use as well because they get ditched upon reentry.

Helium is used because it provides more pressure, 3 or 4 percent, when forcing propellant out of the engines. Liquid nitrogen is also difficult to store and can explode if the tank pressurizes when it boils. Apparently the nitrogen physically "mixes" a little bit with the propellant at the nitrogen propellant boundary while the helium provides a more "solid" boundary to push the propellant out.

There was problems with corrosion of engine parts in Florida's humid air so they were sealed up before shipment. There is talk that maybe the protective seals were opened to test the parts but weren't resealed again. The thrusters worked okay in test conditions where they were made. To fix thruster problems with the first uncrewed test flight attempt, the service module was replaced.
 
Where's Nils Bergenholm and the inertialess drive when you need them?
 
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