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NASA criticised for sticking to imperial units

GlennB said:
Nothing to discuss. NASA is stupid..
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From the article:
NASA recently calculated that converting the relevant drawings, software and documentation to the "International System" of units (SI) would cost a total of $370 million – almost half the cost of a 2009 shuttle launch, which costs a total of $759 million. "We found the cost of converting to SI would exceed what we can afford," says Hautaluoma.
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So sticking to budget is "stupid"? Okay.
 
roger said:
From the article:

So sticking to budget is "stupid"? Okay.
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We live a the world of joint ventures. Far more will be saved in the long run than the "half a shuttle launch" cost of converting now.

The Mars Climate Orbiter failed at huge cost for just such a reason.
 
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roger said:
From the article:

So sticking to budget is "stupid"? Okay.
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What would be the savings in the long run? What with being able to use systems/software from 'the other guys'?

Weird reasoning from the organisation that embodies the 'a stitch in time saves nine' paradigm.
 
Darat said:
At times it can be.
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Yes, it can. Is it in this instance? The claim is that there is nothing to discuss.

Look at it this way. I assume your car in in metric units. Go ahead and try to strap on a bunch of imperial unit engine parts to your car. Not going to be easy, and not worth the expense. Better to just stick to metric, and wait until you build a car with a small block Chevy engine before going to imperial.

In this case it's a new program, but they are reusing shuttle parts in imperial. Is it worth redoing all of that old work? I don't know the answer to that, and no matter how many pages this thread gets to, I don't think we can armchair quarterback this. But if they can't get the money from Congress, the decision is pretty stark - stay with imperial, and get the project done, or just cancel the project. Yes, perhaps a cost study would show that in the long term sticking with imperial would cost, say, $1B over the life of the program. But if you don't have the money, you don't have the money.

Engineers face these kinds of decisions every day. I'm a software engineer. When dealing with old code, it's always substandard. The question is: revise, replace, or deal. More often than not, the decision is to just deal. Almost all technology in the military is obsolete in one form or another (don't nitpick with all the obvious counterexamples please). It's a necessity due to long lead times, extensive testing, etc. Wasn't the shuttle flying with core memory? It's the kind of thing to drive you crazy, but you can't just buy a modern PC and slap it in there - that little decision, easy to do in the commercial space, means hundreds of millions of dollars in rewriting code, retesting things, etc. So, you deal.

Naturally, it would have been nice for NASA to switch to metric for a new program - a perfect time to do so. But they are reusing old technology, and so it becomes an issue. Rework the old proven technology (never a perfectly safe thing to do), stick with the old units, or use a frankenstein approach of some imperial, some metric. We already have examples of failure when you mix units like that. None of the decisions are easy. I wouldn't want to be the guy in charge of making this decision. No matter which decision you make there are failure paths, and you are going to be criticized and second guessed. I applaud the decision to not go with the politically expedient decision. Was it the "right" decision? Who knows? I think it is beyond anyone's knowledge to really say, even the decision maker's. But in this case what was the alternative? Shut down the program, or introduce unknown risks for the life fo the program by mixing units.
 
Molinaro said:
No, stupid is doing the drawings without SI units in the 1st place.
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The drawings were done in the 70s, based on a large infrastructure at the time using imperial units. So they should have mixed units back then, tossed everything that NASA owned, rewritten all computer code, or what?
 
Darat said:
Do you mean this one: http://edition.cnn.com/TECH/space/9909/30/mars.metric.02/
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I don't even have to go that far from my experiences; my university (dutch), a british and a german university were doing a joint project on autonomous mobile robots...

Well, it was a good example of non-comms: we did everything in centimeters, the germans in millimeters and the brits in Inches.

Darn, that robot crashed into nearly everything it could crash! :)
 
GlennB said:
We live a the world of joint ventures. Far more will be saved in the long run than the "half a shuttle launch" cost of converting now.
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Quite probably. Where do you suggest they get the money?
 
roger said:
The drawings were done in the 70s, based on a large infrastructure at the time using imperial units. So they should have mixed units back then, tossed everything that NASA owned, rewritten all computer code, or what?
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When I replied I had not realized that these were not new drawings done for the new design.
 
roger said:
The drawings were done in the 70s, based on a large infrastructure at the time using imperial units. So they should have mixed units back then, tossed everything that NASA owned, rewritten all computer code, or what?
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Soooo.... at what point later on did they add the SI units? Or haven't they started at all yet?
 
Molinaro said:
When I replied I had not realized that these were not new drawings done for the new design.
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I know. But it's frustrating that people just start criticizing what is an enormously difficult decision with multi-decade implications without even reading the article.

The decisions I face in my work are tiny compared to this, yet I can't think of one that couldn't be second guessed, armchair quarterbacked, etc., even with all the data in hand.It's trivial to look at the negative aspects of a complex decision and pile on.

That's not a plea to not look at and criticize what NASA does, and it certainly not a claim that NASA does not make bad decisions, but it is a plea to not just dismiss things without even a cursory look (aimed more at other posters than you Molinaro).
 
roger said:
But in this case what was the alternative? Shut down the program, or introduce unknown risks for the life fo the program by mixing units.
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Meanwhile the rest of the world (apart from Liberia and Myanmar) that might want to get involved in these projects has to convert their designs and software to Imperial? So good of NASA to consider this.
I'd hazard a bet that the EU alone would be willing (if asked) to have a collection to cover the cost.
 
But again, I state, that even though all arguments are true... NASA as a forward looking organisation should be able to see that it will have at least some benefits to finally being able to purchase Chinese equipment.... :)
 
realpaladin said:
Soooo.... at what point later on did they add the SI units? Or haven't they started at all yet?
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I'm not entirely sure what you are asking. Did you read the article?

NASA started with English units. We are talking the beginnings - suborbital launches, then moon landings, etc. All done in imperial for better or worse. Easy to say they should have used metric, but all of the US industry was English at that time.

For every new program, and revision, they can go to congress and say "gimme $3B, I've cut the program to the bone, we are reusing tons of stuff", or they can say "gimme $6 million, we are redoing everything in metric to make Europe happy one day". Guess which one would get turned down. :)

Then Congress comes along and mandates that NASA start switching over to metric.

Is NASA doing everything they can within budgets to do that? I dunno. Neither does anyone posting here, unless they are employed specifically to track exactly that point. Surely you see it is not a trivial thing to do. As I mentioned earlier, the shuttle was flying with core memory because of the long lead time between initial design and development and flight. Congress never gives all the money you'd want, so you decide - use your budget to get rid of core memory, and scrap or seriously delay other programs (which means scraping science in favor of engineering), or do you deal? It's easy to say NASA is not doing enough, but are they getting the money to do it? Should they expend their effort and money on normalizing the engineering, or continue to pursue new science on a shoestring budget? Not really an easy answer, is it? Especially when Congress said "switch to metric" (something I'd love to see) Congress did not also say "and here is the $6B you'll need to do that in a timely manner".
 
The SI was adopted in 1960. How long will it take before the U.S. gets on board?
 
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