Shuttle Launch Delayed

fizzix writes "Weather has delayed the launch of Discovery to tomorrow (Sunday the 2nd), but not everyone thinks it is ready to go. CNN reports both the chief engineer and the chief safety officer gave it a 'no go' for launch. Despite their reservations, barring inclement weather the shuttle is planned to liftoff at 3:26 ET." Update: 07/02 05:00 GMT by Z : I said launch not lauch. Fixed headline.

Comments

I don't get it.

[Carnage Pants]

Two people who are obviously very high up on the pecking order around there say, "No-go," and and yet it's still decided the shuttle is going to launch. Is it just me, or are we asking for another disaster?

From the article ...

[Sonic McTails]

"Earlier Saturday mission managers decided a problem with a thermostat in one of Discovery's thrusters, which was showing a reading in the 80s when it should have been in the 60s, was not dangerous and it could be fixed once the shuttle was in orbit."

Given the fact that foam striking the side of the Columbia during takeoff wasn't considered dangerous, I'm suprised they didn't stop to recheck everything before hand. When it comes down to rechecking everything and delaying the mission for a little longer vs. the millions lost and the following PR hit, the answer pretty obvious. You could say "it could never happen", but try and tell that to the crews of the Changeller and the Columbia.

Re:From the article ...

[tftp]

Rechecking "everything" "by hand" on the launchpad? With cryogenic fuel in the tanks? I think that's unreasonable given the mildness of the problem. It would not be a little delay.

There is another reason - if you get a week and decide to recheck everything, chances are good that you will find a lot of things out of calibration, if not outright defective. And even if you replace them all, by the time you are ready to check again something else will be broken, and so you do some more replacements... ad infinitum. That is because when a machine has 1,000,000 components, each component has to be exceptionally, impossibly reliable.

This particular machine flew to the orbit and back many times already, and many parts may be approaching their failure points. But you can't know that - modern science can't see a future crack in a turbine's blade, and once the crack develops you have about 0.001 seconds before a major destructive event.

That's why many airplane parts are tested on the ground until they start failing, and then a service life is set for them that is way lower than what was seen during the tests. And these parts are replaced after certain number of hours not because they are faulty, but because they might be faulty, and we can't check if they still have some life left in them or not.

But in case of STS there is only very limited knowledge about many parts, as technicians keep discovering totally unexpected wear-related failures all over the orbiter, whenever they get to service it. So we don't really know how long this cryogenic pump or that high pressure pipe or that O-ring can last, since Shuttles are the test article in itself. That's why two missions were lost - because there was no good understanding, beyond a few guesses, of what the materials and the parts are capable of. There -still- is no understanding of many parts, aside from the tiles and RCC panels who were tested exhaustively and hopefully well enough by now.

So, for example, when they say "this thermostat in that thruster does not matter..." they likely only evaluate some expected fault scenario, assuming things that they don't know for sure. For example, if a sensor is misreading the fuel temperature it's one issue. But if it does that because there is an intermittent short, and it may ignite the fuel, that's a very different issue.

This way if they don't check everything they at least can launch, and we already know that the chance of failure should not be higher than 2% - likely less, since the previous problems had been fixed. But if they check for everything they will never fly, and if they ever do then something else will break just after they finished checking. It's just statistics, and game of chance.

Lauch?

[Anonymous Coward]

Whats "lauch"?

Seriously, Slashdot is read by millions of people and yet it lacks the basic courtesy and professionalism that any media outlet should have. How can this thing be taken seriously?

Re:Lauch?

[Bodrius]

They aren't? Then why are they posted by 'editors', who are free to reject them?

I think "editorial oversight" normally has a function that is a bit different than detecting typos, and it has more to do with what Slashdot Editors (gasp!) are doing in a binary fashion: reviewing content for quality, style and fact-checking, to decide what gets published.

Spelling, or even a basic respect of grammar, IS a question of professionalism, in and out of media publications.

I agree that the function of the Slashdot editor is not to convert every post into a masterpiece of wit and literary style, but a run on the spell-checker wouldn't hurt anywhere near what you describe.
I'd expect it would take less time than a dup-check, which is badly needed as well.

Chief Safety Officer

[Anonymous Coward]

If the chief safety officer can't cancel a launch due to safety concerns, what's the point of having a chief safety officer?

Re:Chief Safety Officer

[evanbd]

Well, the CSO didn't choose to appeal the decision. Basically the CSO and chief engineer are worried about the loss of the vehicle, but not the crew. Everyone agrees the crew will be safe, since they plan to check out the tiles etc in orbit, and keep the crew in the ISS and land the shuttle remotely if it looks bad.

Griffin is taking a calculated risk -- he knows the shuttle might be lost, but has taken steps to make sure the crew isn't.

So basically, they object and think it's the wrong decision, but they believe that having gone on record as saying that is sufficient -- they don't think there's a need to override the person in charge of risk assessment since what's at risk is only the spacecraft and not the crew. Whether to risk the craft is legitimately a monetary / political decision, not a safety one, since the crew should be fine either way.

Re:Everybody says no-go...

[db32]

Uhm...might wanna recheck some things. Republicans are the ones that were responsible for that little lying punk NASA PR guy that demanded Big Bang info be removed from the NASA sites and replaced with right wing fundamentalist creationism stuff. If its intentional, its because they view space as having no value because god is coming back for us right here, and soon.

Personally...I think the greatest irony would be God, Jesus and friends standing on some remote place far on the other side of creation saying "Geeze dad, I woulda thought they could have made it here by now..."

Hold on

[Umbral Blot]

So if the engineer says no, and the safety officer says no then who is saying yes? Whose opinion could be more important than these two people?

Re:End the damn program already

[YrWrstNtmr]

25 years of this program and with nothing to show for it. It's getting damned embarrassing and is really starting to reflect America as the stagnant dying empire it is.

Really. And has anyone else on the planet done any better? Going into space is hard, if you haven't noticed.
The Russians? Ok, they can launch Soyuz. Literally, a taxi. 3 people and not much else.
The Chinese? Recreating a 40 year old, 1 man orbital flight.
Commercial efforts so far? Almost, but not quite, recreating a 57 year old X-15 flight, courtesy of a couple of very rich angels. Commercial efforts will get there, but not anytime soon. Gotta satisfy those shareholders.

...dying empire...

You got anything better?

Re:I was there ...

[mwoliver]

If you have lived in Florida for any length of time you would realize that weather can, and often does, change in the span of minutes. With the hours needed to prepare for a launch, they could have GUESSED but not KNOWN that the weather was going to be bad exactly when their window was going to close. The paranoid should appreciate the opportunity to test all of the systems in preparation for a launch, but maybe I am guilty of a 'glass is half full' attitude.

Sometimes, folks who think they know a whole lot need to just sit back and trust the folks who REALLY DO KNOW A LOT.

How could he ever approve a launch?

[khallow]

I'm not clear on the level of risk or the job requirements of the Chief Safety Officer, but it appears to me that a key problem is merely that the Shuttle cannot achieve the level of safety that the chief safety officer is supposed to uphold. It has somewhere around 1-2% failure rate and currently there has only been one launch since the changes after the Columbia launches. Given the advanced age of the remaining vehicles and the lack of progress in reducing tile damage from ice, it sounds like the Chief Safety Officer was in an untenable situation.

In other words, the CSO probably can only approve if an unreasonable (for what they have) level of safety is achieved. Hence, they are likely to be ignored because their requirements cannot be met.