Updates Boeing's CST-100 Starliner

Thunder Chicken

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I get "REDUNDANCY"... :unsure:
Yeah, that's great, but when you burn through two layers of redundancy and finally get to a layer that works for what should be an operational OMS on its first use, that's troublesome.

It's like fixing a problem of getting repeated daily flat tire failures by throwing more cheap spare tires in the trunk of your car. Yeah, I guess you can get to work that way, but I would rather expect to be able to safely drive to work and back on the same set of tires. The right solution is to put proper tires on the vehicle and keep a redundant spare for the off chance that I have a failure. Having spares isn't my plan A to get to work, it's my plan B.

The right solution is to put a properly functioning OMS on the vehicle and not bank on redundancy to save you for routine operations. If they suffered 2 out of 3 failures on the very first operation, what would be the probability of eventually seeing a 3 out of 3 failure during the entire mission? The answer to that is: too damned high.
 

GLS

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Yeah, that's great, but when you burn through two layers of redundancy and finally get to a layer that works for what should be an operational OMS on its first use, that's troublesome.

It's like fixing a problem of getting repeated daily flat tire failures by throwing more cheap spare tires in the trunk of your car. Yeah, I guess you can get to work that way, but I would rather expect to be able to safely drive to work and back on the same set of tires. The right solution is to put proper tires on the vehicle and keep a redundant spare for the off chance that I have a failure. Having spares isn't my plan A to get to work, it's my plan B.

The right solution is to put a properly functioning OMS on the vehicle and not bank on redundancy to save you for routine operations. If they suffered 2 out of 3 failures on the very first operation, what would be the probability of eventually seeing a 3 out of 3 failure during the entire mission? The answer to that is: too damned high.
Yes, it's 2 out of 3 failed, which of course is serious, but there are some questions I don't know the answer to and I think are important:
a) what "failed" exactly? I read that it was low thrust, but that could be clogged line, or valve not opening fully or "just" a sensor or wiring going kaput and the hardware is fine;
b) if that 3º thruster goes, does that "fatally wound" the control? I'd guess not, as Skylab 3 docked with only 3 quads, and when another leaked they where still safe enough to undock and deorbit with only 2. But again, CST-100 is not the CSM, and it has a computer inside instead of Al Bean.
 

N_Molson

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Things tend to fail in space. As long as the spacecraft doesn't suffer spontaneous uncontrolled disassembly flight is nominal ?

I say "Go flight !" (y) :cool:
 

Thunder Chicken

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Yes, it's 2 out of 3 failed, which of course is serious, but there are some questions I don't know the answer to and I think are important:
a) what "failed" exactly? I read that it was low thrust, but that could be clogged line, or valve not opening fully or "just" a sensor or wiring going kaput and the hardware is fine;
Boeing or NASA don't yet know either, which means that they don't fully understand this vehicle yet.
b) if that 3º thruster goes, does that "fatally wound" the control? I'd guess not, as Skylab 3 docked with only 3 quads, and when another leaked they where still safe enough to undock and deorbit with only 2. But again, CST-100 is not the CSM, and it has a computer inside instead of Al Bean.
What other option did Skylab 3 have other than to run with it? That was spaceflight back in the day when they were flying new hardware with test pilots. The tolerance for risk was far higher back then.

Asking "Is this such a big deal?" is the sort of leading question asked by project and flight managers that leads to the normalization of deviance in the face of budget and schedule pressures and ultimately to dead astronauts. The right way to deal with it is assume it IS a big deal and investigate it to the very bottom, but that may be politically unsavory. 2 failed OFTs would not be good for Boeing.

This all echoes what has happened over and over in the past, with Apollo 1, Challenger, Columbia, etc.. The chance to avoid the potential disaster will hinge on how they address this. Maybe it's minor, maybe it's not.
 

Frilock

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I really hope NASA forces another unmanned flight of this thing before they allow people on board. 'Redundancy' shouldn't ever be your first line of defense. This is exactly how at least 14 people died. If NASA allows Boeing to crew a vehicle that lost 2 of its 3 primary OMS, it shows they will just never learn their lesson and shouldn't be allowed a manned program again.
 

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I really hope NASA forces another unmanned flight of this thing before they allow people on board.
Unmanned test flights WASTE A BOOSTER AND SPACECRAFT! Fly it manned with professional test pilots on board. They are trained for handling emergencies, and realistically, a first flight of a spacecraft isn’t much riskier than the first flight of an aircraft. Sure, a spacecraft can kill you more creatively, but they are TEST PILOTS! If crew had been onboard OFT-1, they would have taken manual control, fixed the timer thing, and proceeded with a nominal mission. And don’t get me started on unmanned Artemis 1…
 

GLS

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What other option did Skylab 3 have other than to run with it? That was spaceflight back in the day when they were flying new hardware with test pilots. The tolerance for risk was far higher back then.
They had a rescue vehicle on standby. And by 1973, Apollo wasn't really "new hardware".


Asking "Is this such a big deal?" is the sort of leading question asked by project and flight managers that leads to the normalization of deviance in the face of budget and schedule pressures and ultimately to dead astronauts. The right way to deal with it is assume it IS a big deal and investigate it to the very bottom, but that may be politically unsavory. 2 failed OFTs would not be good for Boeing.

This all echoes what has happened over and over in the past, with Apollo 1, Challenger, Columbia, etc.. The chance to avoid the potential disaster will hinge on how they address this. Maybe it's minor, maybe it's not.

I really hope NASA forces another unmanned flight of this thing before they allow people on board. 'Redundancy' shouldn't ever be your first line of defense. This is exactly how at least 14 people died. If NASA allows Boeing to crew a vehicle that lost 2 of its 3 primary OMS, it shows they will just never learn their lesson and shouldn't be allowed a manned program again.
AFAIK, they lost 2 out of 3 aft-facing thrusters on 1 of the 4 pods so, if the math doesn't fail me, that would be 2 out of 12 total in that axis. Still, of course it needs to be looked at, like every issue, on every vehicle. I'm not inside the valve issues they had, but I don't think this is related (the thrusters apparently fired, just not well enough, while the other valves were "welded" shut).

Yes, asking "Is this such a big deal?" is needed, otherwise you come home after any part fails.
I'm not selling CST-100 or defending Boeing here, but I'm sure things failed in Dragon and nobody is screaming "space disaster coming!!!". Didn't a Dragon blow up on the ground?

Redundancy is what brought CST-100 to 100m of the ISS and closing (apparently safely). Even the best designed systems fail, and when that happens in-flight, redundancy is all there is left.
 

GLS

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Docking delayed until 23:50 UTC due to lighting.
 

Frilock

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They had a rescue vehicle on standby. And by 1973, Apollo wasn't really "new hardware".





AFAIK, they lost 2 out of 3 aft-facing thrusters on 1 of the 4 pods so, if the math doesn't fail me, that would be 2 out of 12 total in that axis. Still, of course it needs to be looked at, like every issue, on every vehicle. I'm not inside the valve issues they had, but I don't think this is related (the thrusters apparently fired, just not well enough, while the other valves were "welded" shut).

Yes, asking "Is this such a big deal?" is needed, otherwise you come home after any part fails.
I'm not selling CST-100 or defending Boeing here, but I'm sure things failed in Dragon and nobody is screaming "space disaster coming!!!". Didn't a Dragon blow up on the ground?

Redundancy is what brought CST-100 to 100m of the ISS and closing (apparently safely). Even the best designed systems fail, and when that happens in-flight, redundancy is all there is left.
I'll 100% admit that I'm not in on the technical issues myself and am probably overreacting. I'm just incredibly leery whenever NASA sees something wrong and their attitude is 'Oh that'll be fine'. And yes, that video of that capsule exploding was playing in my head on repeat for the entirety of SpaceX's first crew mission.
 

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I'm just incredibly leery whenever NASA sees something wrong and their attitude is 'Oh that'll be fine'. And yes, that video of that capsule exploding was playing in my head on repeat for the entirety of SpaceX's first crew mission.
Totally agree. That attitude was responsible for Apollo 1, Apollo 13, Challenger, and Columbia.

As far as the SpaceX thing, I’d rather ride a vehicle might have some thrusters fail over one that has a tendency to blow up unexpectedly… just sayin’. Difference is, SpaceX is a much smaller company than Boeing, and can move and react much faster. So they fixed their (much more serious) issue quietly and got back to flying.
 

GLS

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30 minute delay in order to retract the docking ring to reset some issue.
 

GLS

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Problem solved and docking is coming up!
 

GLS

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Mechanical connections are done!
...and the remaining electrical connections are done, so hard-dock is complete! :hailprobe:
 
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