Shuttle Assessment Tool was Inferior

An anonymous reader writes " Shuttle report in Houston Chronicle: 'The computer program Boeing engineers used to predict that a debris-damaged Columbia could land safely wasn't much more than a simple chart of past foam damage, accident investigators said Tuesday.'"

Comments

"Just a Spreadsheet" doesn't much matter

[0x69]

They had only guesses as to what kind of material (foam, ice, ice-loaded foam, etc.) hit the wing. Only crude estimates as to how much hit, & where. They'd NEVER done real inspections (ultrasound, X-ray, etc.) of those carbon-carbon composite leading edges (to look for delamination, fractures, internal erosion from oxygen entering through surface pinholes, etc.) I haven't heard that they had ANY real test data from larger hits.

In this context, it doesn't much matter whether the "program" is half a million lines of gigaflop-sucking Fortran or a Buck Rogers Secret Decoder Ring. They were (fairly contentedly) starved for meaningful input.

GIGO.

Re:"Just a Spreadsheet" doesn't much matter

[The_K4]

Isn't hindsight a great thing? If they had known at the time that their analysis wasn't good enough do you really think they would have used only a spreadsheet? They much have thought that it was ok. Not to mention that even if they HAD said "it's dead" there would have been NO POSSIBLE WAY to save the crew. No matter how the numbers came out, once the foam hit the shuttle and caused the damage, it was naver comming home, and it's crew was going to suffer that fate with it. It was a tragic accident, let's LEARN from it, not point fingers and look down on people who did what they thought was the right thing!

What choice did they have?

[GypC]

Seems like a moot point to me. From what I understand they had no alternative but to attempt a landing. Maybe if they had somehow scraped together another shuttle launch right after the first one they could have all ridden home in the second one? Or maybe fixed the damage to the first one? I doubt it.

Re:What choice did they have?

[sl3xd]

Just like the way they gave up on Apollo 13 after it exploded in space. Oh wait, they got it back safely.

That's a pretty cynical attitude. It also greatly underscores the fact that we nearly lost Apollo 13's crew, for several reasons. In fact, Houston had every reason to expect that Odyssey would break up during re-entry as well; it is a miracle that it didn't. In fact, NASA did as much giving up then as they did with the shuttle. In both cases, it was unrealistic to 'mount a rescue'; spaceflight isn't that commonplace, which is a fact many seem to forget. Launching payloads into orbit isn't a daily or weekly thing; manned spaceflight is even less common; maybe a monthly thing, if that. NASA basically had the choice: Re-enter now, and take our chances, or re-enter later, and take the same chance. With Apollo 13, NASA gave up the moment they told the crew of the Odyssey to do the final retro-burn to re-enter Earth's atmosphere. They had no choice -- if they didn't bring Odyssey down, the crew would die of asphyxiation, or the extreme temperatures of space.

The same choice presented itself with Colombia; a 'rescue' is only slightly more plausable now than it was during Apollo; which is to say, one step above utterly implausable.

The fact of the matter is that in both cases, the craft had to come down if the crew were to have any chance of survival.

For Columbia, docking with Station Alpha was impossible-- wrong orbit, not enough fuel. There was an oxygen reserve for a few days to a week, depending on who you talk to. It's a moot point, since those few days are insufficient to launch any kind of rescue; it takes weeks to get a scheduled shuttle launch going; hell, it takes weeks to get any rocket ready for launch. And it's not like Boeing, Lockheed, Arianne, or Russia have a spare launch vehicle laying around prepped and ready to go for a rainy day; they certainly don't have two, which is the number of Soyuz craft it would take to return the crew back to Earth. It costs serious $$$ to keep a rocket in a 'prepped and ready to go' state; enough so to make it impractical.

There have been many, many cases where the heat shields of a spacecraft were damaged, or uncertain: Friendship 7, Apollo 13, a couple of the Gemini missions, and at least 20% of the shuttle flights. (There were entirely missing tiles when Columbia made its maiden voyage, and this has repeated itself several times on every one of the shuttles that have flown.). All of them turned out well.

So, there was a choice: Die slowly of asphyxiation and/or dehydration, hoping that the (extremely long) odds of survival until a 'rescue' could be mounted would favor you, or take the much more comfortable odds that you will die during re-entry, when death would take a few microseconds?

No matter what option was taken, the crew would still have to go through re-entry; the only difference would be the craft it happens with.

Re:What choice did they have?

[gizmo_mathboy]

...For Columbia, docking with Station Alpha was impossible-- wrong orbit, not enough fuel.

How about they couldn't dock because they didn't have the correct docking mechanism.

If they had enough fuel to get to the Space Station(SS) about the only choice they had to get the crew onto it was to use the 2 space suits to ferry folks from Columbia to the SS. I'm assuming that there is an airlock on the SS that can be used for EVA's.

This might have given folks enough time on the ground to get 4 (need a trained pilot for the return I'm guessing) Soyuz capsules up there and rescure the Columbia crew.

Of course, this crazy scheme depends on there being enough fuel onboard Columbia to get it close to the SS.

I just hope we truly learn from this mistake.

Economics in a country that demands Profit!

[purduephotog]

First, I am an engineer. Alot of you probably are too. What I'm going to say will probably be modded flamebait, etc, but I'm fighting my own battles at work in regards to problems that no one else saw... or care
Alot of the analysis has been attacking the engineers for not asking enough questions. Thats fine and dandy in a 100% hindsight problem- we have a failed shuttle- lets' find out why. Alot of the reviews have been talking about data presentation- thats good too- I went to school for engineering, not marketing, and therefor don't know what a marketer does as to how to present information without getting bogged down in details.
But when it comes straight down to it, it's money, pure and simple. Do you think CAT scans of tiles are inexpenisve? Probably a couple $k each. Do this for every tile. Want to understand turbulence completely (and people that say you can model a chaotic system- just watch the weather channel to know how EASY that is)- that costs money and time. Quite a bit of both, too.
So now you've got budget concerns on projects that aren't funded and you can only skunk work it too much (note- skunk work is done on the side, unpaid overtime/salary, and 'hiding' the cost of equipment time/usage under a variety of things. It's amazing what you can do sometimes).
Now and then you get lucky and management comes around... funds your project, everyone gets paid with a little back in the jar for the next skunk project... then again, what does management usually know? zip. Just those bottom line numbers
Now obviously there was a bit of scaleup issue. I'm not comfortable with a 5x scaleup on some jobs, much less a 640x prediction- thats me personally. And the analysis that reads safety as a failure, instead of safety as a problem is dead on (1/3 the O-ring). But don't go too hard on the engineers- many comments are headed that way. Just remember under-funding answers the important questions, and may lop a bunch of details under assumptions... and every now and then you get bit in the ass... hard.