Can someone explain the use of Helium on the Starliner and

[Swan]

also what would the weight of the Helium be on the craft so that a thrust to weight comparison could be made? Also, why wouldn't Oxygen be used as this would increase the burn rate when Helium has no such property?

 

[TomS]

also what would the weight of the Helium be on the craft so that a thrust to weight comparison could be made? Also, why wouldn't Oxygen be used as this would increase the burn rate when Helium has no such property?

Starliner (and other rockets, including Falcon 9) uses helium to pressurize the tanks of fuel and oxidizer than feed the thrusters. Using oxygen would be rather interesting (dangerous), especially for the fuel tanks. Trying to pressurize hydrazine with oxygen sounds like a recipe for an explosion.

 

[Swan]

Starliner (and other rockets, including Falcon 9) uses helium to pressurize the tanks of fuel and oxidizer than feed the thrusters. Using oxygen would be rather interesting (dangerous), especially for the fuel tanks. Trying to pressurize hydrazine with oxygen sounds like a recipe for an explosion.

I do not see how the weight and complexity of Helium in stainless or Titanium tanks, along with the valves and gas lines and injectors makes sense, from either a complexity or weight standpoint, but it would be a great way to throw the Chinese in the wrong direction. There is also no reason to use Hydrazine over more common propellants that would be safely amplified by O2. PS. Not everything that NASA says is the truth, never was or will be, not putting them down either just stating the obvious as this is after all a secret system.

 

[TomS]

Sorry, you're just wrong. Hydrazine is used by lots of programs in the US and elsewhere, because it's just the best solution for certain applications. The chemistry/physics isn't really open to debate here.

 

[Swan]

Sorry, you're just wrong. Hydrazine is used by lots of programs in the US and elsewhere, because it's just the best solution for certain applications. The chemistry/physics isn't really open to debate here.

Ah, is that why it failed so badly? I mean what if this same failure repeats not at the space station but on Mars say? One of the stranded astronauts is going blind by the way

 

[publiusr]

I suppose the periodic table just won’t allow a dense inert gas that won’t freeze…stubborn that way.

Now, I have heard of “superchemistry” where molecules can act as a single element/atom…

 

[Swan]

I suppose the periodic table just won’t allow a dense inert gas that won’t freeze…stubborn that way.

Now, I have heard of “superchemistry” where molecules can act as a single element/atom…

Even superchemistry fails, as it did in this instance

 

[TomS]

Ah, is that why it failed so badly? I mean what if this same failure repeats not at the space station but on Mars say?

The same tech works fine on Crew Dragon, and many, many other spacecraft. Boeing just seems to have problems with their specific implementation on Starliner.

One of the stranded astronauts is going blind by the way

No, that's not true. You've been reading Indian newspapers, I suspect. That's basically the only place I can find claims like that.

The truth is that Sunita Williams had an eye exam on the station, as did several other astronauts. The initial reports suggest this was just routine data collection for research (the astronauts have also had hearing tests). But some reports, mostly Indian, have claimed without evidence that this is a sign that she has some dire health issue. It's not the case.

 

[southwestforests]

Also, why wouldn't Oxygen be used as this would increase the burn rate when Helium has no such property?

Helium isn't there so it can react with the fuel chemicals - it is there precisely because it is an inert chemical and will NOT react wit the oxygen.

Here, since you don't trust NASA as an information source, read this from Reuters by Nivedita Bhattacharjee, as reprinted in The Hindu newspaper,

https://www.reuters.com/science/what-is-helium-why-is-it-used-rockets-2024-09-07/

What is helium and why is it used in rockets?

Helium is used to pressurize fuel tanks, ensuring fuel flows to the rocket’s engines without interruption; and for cooling systems.

www.thehindu.com

Why helium?​

Helium is inert - it does not react with other substances or combust - and its atomic number is 2, making it the second lightest element after hydrogen.

Rockets need to achieve specific speeds and altitude to reach and maintain orbit. A heavier rocket requires more energy, not only increasing fuel consumption but also needing more powerful engines, which are more expensive to develop, test, and maintain.

Helium also has a very low boiling point (-268.9° C), allowing it to remain a gas even in super-cold environments, an important feature because many rocket fuels are stored in that temperature range.

The gas is non-toxic, but cannot be breathed on its own, because it displaces the oxygen humans need for respiration.

How is it used?​

Helium is used to pressurize fuel tanks, ensuring fuel flows to the rocket’s engines without interruption; and for cooling systems.

As fuel and oxidiser are burned in the rocket’s engines, helium fills the resulting empty space in the tanks, maintaining the overall pressure inside.

Because it is non-reactive, it can safely mingle with the tanks’ residual contents.

Is it prone to leaks?​

Helium’s small atomic size and low molecular weight mean its atoms can escape through small gaps or seals in storage tanks and fuel systems.

But because there is very little helium in the Earth’s atmosphere, leaks can be easily detected - making the gas important for spotting potential faults in a rocket or spacecraft’s fuel systems.

...

Are there alternatives?​

Some rocket launches have experimented with gases such as argon and nitrogen, which are also inert and can sometimes be cheaper. Helium, however, is much more prevalent in the industry.
...

Published - September 07, 2024 04:41 pm IST

 

[southwestforests]

I do not see how the weight and complexity of Helium in stainless or Titanium tanks, along with the valves and gas lines and injectors makes sense, from either a complexity or weight standpoint, but it would be a great way to throw the Chinese in the wrong direction.

Although I don't have access to what specific logic is the foundation behind that statement, is true that any and all concern about what Helium is used for in rocket fuel and oxidizer systems and what the Chinese do or know, or do not do or do not know, about that is an issue which has its foundation purely within the realm of imagination -- helium has been used as a non-reactive tank pressurizing gas since the 1960s -- half a century ago.

 

[Hobbes]

I do not see how the weight and complexity of Helium in stainless or Titanium tanks, along with the valves and gas lines and injectors makes sense, from either a complexity or weight standpoint,

Helium is used because the propellant tanks have to be pressurized, preferably to a constant pressure during the flight. Two methods are available to do that:
1. pressurization with a separate gas. This is carried in a high-pressure tank and gradually fed into the main propellant tank. You need a gas that will not react with the propellant (e.g. you can't use oxygen, because adding oxygen to the fuel tank creates a combustible gas mix in the tank). You need a gas that will stay gaseous at the temperature of the tank (so in a tank that contains liquid oxygen, you can't use nitrogen because the nitrogen would liquefy and fail to keep the pressure up). Helium is the best option. It is inert and has a lower boiling point than any propellant.
2. Autogenous pressurization, where some of the propellant is heated up to boil it. This makes the plumbing more complicated (you need a circuit for pumping the propellant through the engine to warm it up) and is only available when the engines are running, but it can be more efficient because you don't need to carry a gas that won't contribute to combustion.

 

[Nicknick]

Maybe Argon could be a cheaper alternative, the boiling point of -185° C should be low enough. It would increase the weight somewhat, but might be less prone to leakage.

 

[Swan]

Helium is used because the propellant tanks have to be pressurized, preferably to a constant pressure during the flight. Two methods are available to do that:
1. pressurization with a separate gas. This is carried in a high-pressure tank and gradually fed into the main propellant tank. You need a gas that will not react with the propellant (e.g. you can't use oxygen, because adding oxygen to the fuel tank creates a combustible gas mix in the tank). You need a gas that will stay gaseous at the temperature of the tank (so in a tank that contains liquid oxygen, you can't use nitrogen because the nitrogen would liquefy and fail to keep the pressure up). Helium is the best option. It is inert and has a lower boiling point than any propellant.
2. Autogenous pressurization, where some of the propellant is heated up to boil it. This makes the plumbing more complicated (you need a circuit for pumping the propellant through the engine to warm it up) and is only available when the engines are running, but it can be more efficient because you don't need to carry a gas that won't contribute to combustion.

Perhaps that is the theory as to what should happen, but something failed along the way. Also no one can explain how if there were 5 known Helium leaks on the way up as to how these leaks were plugged in order to have any Helium pressure for the return trip. So who thinks that they have this above top secret info and that they have clearance to disseminate the answer here

 

[Swan]

The same tech works fine on Crew Dragon, and many, many other spacecraft. Boeing just seems to have problems with their specific implementation on Starliner.



No, that's not true. You've been reading Indian newspapers, I suspect. That's basically the only place I can find claims like that.

The truth is that Sunita Williams had an eye exam on the station, as did several other astronauts. The initial reports suggest this was just routine data collection for research (the astronauts have also had hearing tests). But some reports, mostly Indian, have claimed without evidence that this is a sign that she has some dire health issue. It's not the case.

NASA says different as this came from a NASA affiliated page

Crew members aboard the International Space Station conducted a variety of scientific investigations during the week ending July 28, 2023, including conducting sessions for ISAFE, which measures changes in astronaut’s eyes, brain, and blood vessels during missions of varying lengths.

Astronauts experience changes to their eyes and vision during spaceflight, a phenomenon known as Spaceflight Associated Neuro-Ocular Syndrome (SANS). Microgravity causes a person’s blood and cerebrospinal fluid to shift toward the head, and researchers suspect that these fluid shifts are an underlying cause of SANS.

SANS changes are at present irreversible and lack of vision has a more common name, which is progressive blindness

 

[TomS]

NASA says different as this came from a NASA affiliated page

Crew members aboard the International Space Station conducted a variety of scientific investigations during the week ending July 28, 2023, including conducting sessions for ISAFE, which measures changes in astronaut’s eyes, brain, and blood vessels during missions of varying lengths.

Astronauts experience changes to their eyes and vision during spaceflight, a phenomenon known as Spaceflight Associated Neuro-Ocular Syndrome (SANS). Microgravity causes a person’s blood and cerebrospinal fluid to shift toward the head, and researchers suspect that these fluid shifts are an underlying cause of SANS.

SANS changes are at present irreversible and lack of vision has a more common name, which is progressive blindness

Link, because you didn't bother to provide it.

Science in Space: July 28, 2023 - Astronaut Vision - NASA

During the week ending July 28, 2023, crew members conducted science investigations related to astronaut vision during varying mission lengths.

www.nasa.gov

Note this is from July 2023, a year before Sunita Williams even arrived at ISS.

Here is the NASA blog entry for the day where Williams had her eyes checked.

Blood Tests, Eye Scans on Station Helping Doctors Improve Crew Health

Blood sample collections and eye scans took a big part of the day on Tuesday as the International Space Station residents continuously explore how living in space affects their bodies. The two crews representing Expedition 71 and NASA’s Boeing Crew Flight Test also trained for robotics...

blogs.nasa.gov

No indication that this was anything but routine research. If you search that blog, you'll see eye testing of the entire crew periodically. (Also hearing, cognitive functions, etc.) You'll also see that Williams has a rather full schedule, not what you'd expect for someone who is going blind.

 

[Byeman]

Perhaps that is the theory as to what should happen, but something failed along the way. Also no one can explain how if there were 5 known Helium leaks on the way up as to how these leaks were plugged in order to have any Helium pressure for the return trip. So who thinks that they have this above top secret info and that they have clearance to disseminate the answer here

there is no such security on these missions. These are not military and so things such as clearances and level like top secret don't apply.
As far as leaks, they can isolate the individual thrusters and their leaks. This common practice to have isolation valves.

 

[Byeman]

I do not see how the weight and complexity of Helium in stainless or Titanium tanks, along with the valves and gas lines and injectors makes sense, from either a complexity or weight standpoint, but it would be a great way to throw the Chinese in the wrong direction. There is also no reason to use Hydrazine over more common propellants that would be safely amplified by O2.

Hydrazine is the the most common propellant for spacecraft. Hydrazine can be used as a mono propellant which does reduced complexity. But when a higher ISP is desired, N2O4 is used as an oxidizer with a hydrazine derivative. The main reason hydrazine is used is because it is storable for long periods. It can last for decades unlike other propellants,

PS. Not everything that NASA says is the truth, never was or will be, not putting them down either just stating the obvious as this is after all a secret system.

PS. You are wrong here in many ways here and this is not a "secret system". Why would NASA not say it is not the truth?

 

[Swan]

Link, because you didn't bother to provide it.

Science in Space: July 28, 2023 - Astronaut Vision - NASA

During the week ending July 28, 2023, crew members conducted science investigations related to astronaut vision during varying mission lengths.

www.nasa.gov

Note this is from July 2023, a year before Sunita Williams even arrived at ISS.

Here is the NASA blog entry for the day where Williams had her eyes checked.

Blood Tests, Eye Scans on Station Helping Doctors Improve Crew Health

Blood sample collections and eye scans took a big part of the day on Tuesday as the International Space Station residents continuously explore how living in space affects their bodies. The two crews representing Expedition 71 and NASA’s Boeing Crew Flight Test also trained for robotics...

blogs.nasa.gov

No indication that this was anything but routine research. If you search that blog, you'll see eye testing of the entire crew periodically. (Also hearing, cognitive functions, etc.) You'll also see that Williams has a rather full schedule, not what you'd expect for someone who is going blind.

Exactly as the vision problems caused by space are not particular to Sunita Williams though she is exceptionally vulnerable and is suffering from permanent vision reduction

Why does it matter that this syndrome was previously identified? The woman is still going blind and still they refuse to bring her back ASAP.

https://www.nasa.gov/missions/station/iss-research/science-in-space-july-28-2023-astronaut-vision/#:~:text=Astronauts experience changes to their,an underlying cause of SANS.

 

[Byeman]

Why does it matter that this syndrome was previously identified? The woman is still going blind and still they refuse to bring her back ASAP.

https://www.nasa.gov/missions/station/iss-research/science-in-space-july-28-2023-astronaut-vision/#:~:text=Astronauts experience changes to their,an underlying cause of SANS.

She is not going blind. And what don't you understand about "Postflight recovery took 30 to 90 days."

 

[Hobbes]

Perhaps that is the theory as to what should happen, but something failed along the way. Also no one can explain how if there were 5 known Helium leaks on the way up as to how these leaks were plugged in order to have any Helium pressure for the return trip. So who thinks that they have this above top secret info and that they have clearance to disseminate the answer here

What failed is the Starliner design and/or testing process. Helium has been used on thousands of launches. It is the standard solution for tank pressurization, and its use is very well understood.

"no one can explain how"

Sure we can. A valve was closed upstream of the leak.

 

[Swan]

She is not going blind. And what don't you understand about "Postflight recovery took 30 to 90 days."

Visual Impairment Intracranial Pressure Syndrome​

NASA identified the problem as Visual Impairment Intracranial Pressure Syndrome (VIIP), which is now knowns as Space-Associated Neuro-Ocular Syndrome (SANS). This syndrome affects 80% of astronauts on long-duration missions in space. Interestingly, many astronauts suffer from visual changes that are irreversible even after returning to Earth.

https://southwesteye.com/eye-care/h... affects 80% of,even after returning to Earth.

Argue with the eye doctors, not me

 

[Swan]

What failed is the Starliner design and/or testing process. Helium has been used on thousands of launches. It is the standard solution for tank pressurization, and its use is very well understood.

"no one can explain how"

Sure we can. A valve was closed upstream of the leak.

Excellent, so something different was secretly done here that may not even involve Helium. LOL do you believe that the government is required to tell the truth to Americans who include foreign spies?

 

[TomS]

Visual Impairment Intracranial Pressure Syndrome​

NASA identified the problem as Visual Impairment Intracranial Pressure Syndrome (VIIP), which is now knowns as Space-Associated Neuro-Ocular Syndrome (SANS). This syndrome affects 80% of astronauts on long-duration missions in space. Interestingly, many astronauts suffer from visual changes that are irreversible even after returning to Earth.

https://southwesteye.com/eye-care/how-space-travel-affects-eyesight/#:~:text=Visual Impairment Intracranial Pressure Syndrome&text=This syndrome affects 80% of,even after returning to Earth.

Argue with the eye doctors, not me

From the same link, "The only lasting effect is about 1.5 diopter farsighted shift in 7 months on orbit"

That's not going blind, that's needing a new eyeglasses prescription.

And there continues to be zero evidence that Williams is suffering from these conditions at all, much less "more severely" or "going blind."

If she was suffering a severe vision impairment, she would be a hazard on the station and they would likely have brought her home on Starliner or figured a way to get her on the Crew 8 return instead.

Look, it's clear you have absolutely no idea what you are talking about, so I'm going to save us both some typing and just hit Ignore.

 

[Swan]

From the same link, "The only lasting effect is about 1.5 diopter farsighted shift in 7 months on orbit"

That's not going blind, that's needing a new eyeglasses prescription.

And there continues to be zero evidence that Williams is suffering from these conditions at all, much less "more severely" or "going blind."

If she was suffering a severe vision impairment, she would be a hazard on the station and they would likely have brought her home on Starliner or figured a way to get her on the Crew 8 return instead.

Look, it's clear you have absolutely no idea what you are talking about, so I'm going to save us both some typing and just hit Ignore.

Permanent vision reduction means partial blindness. Sunita Williams is losing her sight; her escape flight is docked and still they refuse to bring her home until February. Why?

 

[Byeman]

Excellent, so something different was secretly done here that may not even involve Helium. LOL do you believe that the government is required to tell the truth to Americans who include foreign spies?

a. It wasn't secretly done. it was openly discussed. it did involve helium, it was valves on the helium system.
b. I know how it works. I was in the military and NASA. NASA has no secrets. NASA by law is required to be open and provide information to the public. It just can't provide information of systems it doesn't own. That is up to the system owner. Spies aren't an issue on these items.

 

[Byeman]

Permanent vision reduction means partial blindness.

wrong, it is a change in the shape of the eye and hence a change in visual acuity

that is two issues you have misunderstood.

 

[jstar]

Can we just move on from this? Please?

 

[Hobbes]

Excellent, so something different was secretly done here that may not even involve Helium. LOL do you believe that the government is required to tell the truth to Americans who include foreign spies?

There's going to be an investigation into these issues, and when the results of that investigation is published, we'll know exactly what happened. Likely causes include errors during installation, the use of components not qualified for the environment they're in, etc. There's zero chance they're using a pressurant other than helium.

This is SOP for issues discovered during commercial spaceflight, and can be confirmed by looking up the investigations done in any number of previous issues.

 

[southwestforests]

Can we just move on from this? Please?

Those who are addicted to conspiracy theories appear to be both psychologically and physically incapable of putting down the conspiracy theory and stepping away from the conspiracy theory as though conspiracy theories are some kind of obsessive compulsive thing with roots deep in the psyche where letting go of the conspiracy will create the feeling of being awash in a gale without sails or anchor and there being an immediate threat to the continuation of corporeal existence.
Or, could simply be that they are a troll who really needs to get back to finishing their homework for tomorrow, but, yeah, I do understand the need to take an occasional mental break from said homework.

 

[Swan]

a. It wasn't secretly done. it was openly discussed. it did involve helium, it was valves on the helium system.
b. I know how it works. I was in the military and NASA. NASA has no secrets. NASA by law is required to be open and provide information to the public. It just can't provide information of systems it doesn't own. That is up to the system owner. Spies aren't an issue on these items.

Are you making the claim that there are no secret propulsion systems that are not openly discussed? Is the government using Helium because they said they are? Did you load the Helium? Do you know someone who did? Has the government ever lied to fool Russia before? Why is the USA funding a war in the Ukraine and working with the enemy in space

 

[Swan]

Those who are addicted to conspiracy theories appear to be both psychologically and physically incapable of putting down the conspiracy theory and stepping away from the conspiracy theory as though conspiracy theories are some kind of obsessive compulsive thing with roots deep in the psyche where letting go of the conspiracy will create the feeling of being awash in a gale without sails or anchor and there being an immediate threat to the continuation of corporeal existence.
Or, could simply be that they are a troll who really needs to get back to finishing their homework for tomorrow, but, yeah, I do understand the need to take an occasional mental break from said homework.

I bought Apple computer stock and my son works for the world's largest defense contractor initials LM and I will never be gullible like some people that believe the media because the media never lies

 

[Scott Kenny]

I presume that you know that Boeing also makes jets for the military.

You do understand that those are two separate divisions of a company, right? Anything Boeing Military does is likely classified. Anything Boeing Commercial does is not.

 

[Jemiba]

There may be things not made public indeed, for the sake of the states security, or something like that, but this discussion directly leads into conspiray theories. So, please stop it !

 

[Swan]

You do understand that those are two separate divisions of a company, right? Anything Boeing Military does is likely classified. Anything Boeing Commercial does is not.

Again, Boeing does not have two divisions, it has three divisions, they are Commercial Airplanes; Defense, Space & Security; and Global Services.

 

[DWG]

Again, Boeing does not have two divisions, it has three divisions, they are Commercial Airplanes; Defense, Space & Security; and Global Services.

Which still leaves the statement " those are two separate divisions of a company," perfectly correct.

 

[Arjen]

Actually Boeing Defense, Space and Security handles spacecraft and launchers, Boeing Commercial Airplanes doesn't.

Somewhat beside the point, though. This thread started by OP asking why use helium on Starliner, for which answers were provided. Then the matter of an astronaut going blind came up, with little evidence offered. Also, NASA was supposed to be hiding some unspecified secret possibly connected with sending helium to the ISS, and now we're discussing Boeing's divisions.

I suggest putting a sock in it.

 

[Byeman]

I Did you load the Helium? Do you know someone who did?

No, but I have provided it for other spacecraft. And yes, I know the people that did.

 

[Jemiba]

The original question was answered, what follows is mostly OT and drifting into some sort of conspiracy theories, not supported here and not in general in this forum.
Thread locked