Boeing's Starliner

[Ultimate Steve]

It is probably some obscure thing nobody here could think of. Most software is full of stupid things that make changing the plan difficult... Though I would have expected the capsule to be able to undock itself. There's a few situations where you might want that anyway.

[darthgently]

1 hour ago, tater said:

The thought it that somehow for the actual crew capsule they literally made an "undock" button somehow required to undock, and that in order to bypass it, they need to write code to work around it. The code to actually DO the undock is there, I guess, it's just set to only be triggered by astronauts right now?

I suppose as it is their lifeboat/way-home, it could be seen as a safety thing, no software glitch could undock it unintentionally?

"Open the Starliner door, HAL"

"I'm sorry, Dave, I can't do that.  I've already undocked.  I'm not sure why.  Something about the mission..."

 

[magnemoe]

4 hours ago, tater said:

The thought it that somehow for the actual crew capsule they literally made an "undock" button somehow required to undock, and that in order to bypass it, they need to write code to work around it. The code to actually DO the undock is there, I guess, it's just set to only be triggered by astronauts right now?

I suppose as it is their lifeboat/way-home, it could be seen as a safety thing, no software glitch could undock it unintentionally?

It makes sense, but I say it would be even better with an mechanical block of undocking, think an safety on a gun, not just having it in code. 
And if in code I imagine it would be an flag, require undock button to undock. 

And the undocking has to be synchronized with using thrusters to push away from the station who is automated as default anyway. 

[kerbiloid]

An invisible pin hole.

Spoiler

 

[darthgently]

33 minutes ago, kerbiloid said:

An invisible pin hole.

  Hide contents

 

Ah, yes, the true focus of Operation Paperclip:  safe and secure capsule ejection from space stations

[darthgently]

On 8/2/2024 at 3:10 AM, Jacke said:

The Tweet and Ars Technica article are both from Eric Berger, widely known as hating everything but SpaceX.  I considering anything from him to be at best misinformation and at worse disinformation.  I'd suggest going to direct quotes from NASA.

 

 

[tater]

Welcome to #5.

[darthgently]

Dragon plan likely?

 

 

[Mr. Kerbin]

Eric may be right.

link here

Edited August 7 by Mr. Kerbin

[tater]

I can’t imagine them certifying this vehicle for an operational flight without first testing whatever they fix, even if the crew comes home on Starliner.

[darthgently]

If Butch and Suni are staying until February that would have to be in the running for the longest, if not the longest, unplanned stay in space.  That has to be quite a development to absorb, good and bad.

[tater]

I think it's important to remember that Dragon, while flight-proven, is also, well, not "safe." Space travel is still rather dangerous. Assuming the vehicles meet their spec, they will only lose 1 in 270 flights. So far they've flown 25 times, including cargo (since they're basically the same). So we know it's real safety is at least 1:24 (crew on ISS still has to return). So there's a nonzero chance that they could do one of the "Dragon rescue" options, Starliner returns home nominally, and Dragon suffers a loss.

So the question is not, "Send them home safely on Dragon, or take a risk on Starliner," it is in fact a balance of the risks of the 2 vehicles vs each other. If they believe their own risk estimates, then they assume 1:270 for Dragon, vs whatever they downgrade this particular Starliner to right now. Actually, they calculate risk for ascent, on orbit, and descent, so the remaining risk might in fact be higher for both vehicles than 1:270, dunno how they calculate it.

[tater]

Long thread goes through the self-docking requirements.

[Gargamel]

14 hours ago, darthgently said:

If Butch and Suni are staying until February that would have to be in the running for the longest, if not the longest, unplanned stay in space.  That has to be quite a development to absorb, good and bad.

That was my thought too.    Who’s got the current record for accidental resident of space? 

[AckSed]

39 minutes ago, Gargamel said:

That was my thought too.    Who’s got the current record for accidental resident of space? 

*charges in with upraised finger* That is Sergei Krikalev, who endured nearly a year in space when the USSR fell: https://www.inverse.com/science/sergei-krikalev-the-cosmonaut-without-a-country

[Mikki]

[snip] I hope Suni and Butch have an enjoyable and healthy stay on the station. I think a good solution pops up at some point and they can return safely.

Edited August 9 by Vanamonde
Mind the language, please.

[magnemoe]

4 minutes ago, AckSed said:

*charges in with upraised finger* That is Sergei Krikalev, who endured nearly a year in space when the USSR fell: https://www.inverse.com/science/sergei-krikalev-the-cosmonaut-without-a-country

Thought of him to, however he was not stranded, the issue was was that Russia was not able to send an new crew so station would be unmanned for months, this is likely to destroy it. 
Who brings me to another issue, as I understand its an limit on how long an Soyuz can stay in space. Reason is that the reentry capsule uses H2O2 for its reaction control system and H2O2 breaks down over time. 
I assume reason is that this has to be stored inside the crew cabin where you don't want standard hypergolic. 
 

[StrandedonEarth]

I probably shouldn’t post memes poking fun at poor Starliner, but I can’t help myself. But I’ll acknowledge that the situation  isn’t as bad as depicted…

Spoiler

 

[kerbiloid]

8 hours ago, magnemoe said:

Who brings me to another issue, as I understand its an limit on how long an Soyuz can stay in space. Reason is that the reentry capsule uses H2O2 for its reaction control system and H2O2 breaks down over time. 

He was one of three onboard. Arrived on one ship, returned on another.

Also his first flight was same intercrew, but shorter.

[darthgently]

On 8/7/2024 at 10:24 PM, tater said:

I think it's important to remember that Dragon, while flight-proven, is also, well, not "safe." Space travel is still rather dangerous. Assuming the vehicles meet their spec, they will only lose 1 in 270 flights. So far they've flown 25 times, including cargo (since they're basically the same). So we know it's real safety is at least 1:24 (crew on ISS still has to return). So there's a nonzero chance that they could do one of the "Dragon rescue" options, Starliner returns home nominally, and Dragon suffers a loss.

So the question is not, "Send them home safely on Dragon, or take a risk on Starliner," it is in fact a balance of the risks of the 2 vehicles vs each other. If they believe their own risk estimates, then they assume 1:270 for Dragon, vs whatever they downgrade this particular Starliner to right now. Actually, they calculate risk for ascent, on orbit, and descent, so the remaining risk might in fact be higher for both vehicles than 1:270, dunno how they calculate it.

Good to remember that the 1:270 is a maximum criteria not a target.  Dragon, and many other NASA manned widgets, could be 1:313, 1:420, 1:2,677 or better also.  Only time can really tell the story and only statistically even then.  Dragon might be worse than 1:270 also but doesn't appear likely given the analysis, thus its crew rating

[.50calBMG]

I seem to remember the press making a big deal about starliner being rated for 45 days of spaceflight during the first two delays "extensions", but aren't we coming up on something like double that pretty soon? Was that 45 days of free flight or spaceflight in general?

[tater]

1 hour ago, .50calBMG said:

I seem to remember the press making a big deal about starliner being rated for 45 days of spaceflight during the first two delays "extensions", but aren't we coming up on something like double that pretty soon? Was that 45 days of free flight or spaceflight in general?

Dunno, but the design spec for both CCVs is for a 6 month nominal mission to ISS—which could go long. No idea why shorter battery life could possibly be a thing, it's not like battery tech pushes the TRL.

[tater]

This overview by Scott Manley is good:

 

[DDE]

On 8/4/2024 at 12:56 PM, Mikki said:

Put some junk into starliner and get it back remotly, resolve the issues and move along. Nobody will be harmed. Not even boeing, in fact boeing will regain some lost respect which in the long term may be more valuable than the accountants brain can grasp.

Oh, come on, what's happened to finding oneself in a deep pit and continuing to dig deeper? Thus far it seems to be headed there - hopefully not a LoC, but there's definitely going to be more rounds of stubbornness and embarassment.

Dumb question, maybe I'm late to the party: why was there no contingency planning for return via a different vehicle? Why is SpaceX only now getting the call? Backup suits and seats aren't that expensive to make.

Spoiler

* laughs in Buran-compatible Soyuz *

 

[tater]

52 minutes ago, DDE said:

Dumb question, maybe I'm late to the party: why was there no contingency planning for return via a different vehicle? Why is SpaceX only now getting the call? Backup suits and seats aren't that expensive to make.

They were already working on those contingencies should they ever be needed for crew delivered with Soyuz, actually.