Astronauts Having Trouble With Tranquility Module

Coldeagle writes "Astronauts ran into trouble while trying to connect up the new Tranquility module onto the ISS. A critical insulating cover didn't fit quite right: 'The fabric, multilayered cover is supposed to go between Tranquility and its observation deck, but the metal bars are not locking down properly because of interference from a hand rail or some other structure at the hatch.' One has to wonder if this is another imperial/metric snafu."

Comments

Metric Everywhere

[elzurawka]

Atleast in scientific application there is no reason to use Imperial. Metric makes all calculations simpler, and is accepted by a much larger portion of the world, and should be the standard in all science.

Re:Metric Everywhere

[profplump]

He means that metric makes prefix-changing calculations easier, even though no one ever does those outside of middle school science classes. And he's assuming that you'll ignore the fact the most real-world calculations involve a coefficient that isn't a multiple of 10 because the physical world is not dictated by our measurement system, even when using SI units -- is 6.67300 × 10^-11 m^3 kg^-1 s^-2 somehow easier to use than 1.06891206 × 10^-9 feet^3 pounds-force^-1 s^-2?

Used by a large portion of the world is a good point. There's great value in having everyone use the same system. Of course there's also an enormous cost in switching between systems, and little direct benefit to anyone who was happy with the old system, which is why no one does it.

Re:Metric Everywhere

[AdmiralXyz]

You're absolutely right, but I detect in your voice that you think some people disagree with you. This is something I see a lot, especially from Europeans: the assumption that Americans are actually fanatical supporters of the Imperial system. The truth is, we don't like it (can't speak for the UK, but I suspect it's similar). There isn't anyone in America who actually believes that the Imperial system is easier or more useful. The reason it persists is simply one of tradition, and the enormous expense (in terms of money and headaches) it would take to move the entire country over to a new system.

For example, I have basically no concept in my mind of how far a "kilometer" is. Oh, I know it's .62 miles, and I can usually do the conversion in my head, but I don't have an intuitive, subconscious sense of how far a kilometer is, like I do for a mile. I suspect most people raised on the metric system are the same way for Imperial units, it's just not easy to get a natural sense of the units you didn't grow up with. An entire country of people who don't have an intuitive sense of the units they're using would be chaos.

Re:Metric Everywhere

[socceroos]

Not to mention movies like "the Green Kilometer" - doesn't have the same ring to it.

Re:Metric Everywhere

[navyjeff]

Here's a handy guide to get an intuitive sense of metric measurements.

Re:Metric Everywhere

[Pentium100]

He means that metric makes prefix-changing calculations easier, even though no one ever does those outside of middle school science classes. And he's assuming that you'll ignore the fact the most real-world calculations involve a coefficient that isn't a multiple of 10 because the physical world is not dictated by our measurement system, even when using SI units -- is 6.67300 × 10^-11 m^3 kg^-1 s^-2 somehow easier to use than 1.06891206 × 10^-9 feet^3 pounds-force^-1 s^-2?

Prefix changing calculations are used a lot even outside middle school. If you have measurements in smaller units (mL, cups) and need to convert them to larger units (m^3, ft^3) because you have some table which only lists the larger units (for example a table of volume densities of various materials), then you need to do more complex calculations in the imperial system.

1mL=1e-6 m^3
1cup = 0.00835503472 ft^3

and here is when you get the extra complexity.

that's the point. While the coefficients that were observed in the real world rarely match our units evenly, with metric system at least the units themselves are a power of 10 of larger and smaller units.

Re:Metric Everywhere

[Anonymous Coward]

Oh well, re-adjusting your intuition to new units of measure isn't nearly as hard as it seems at first, before you actually have to do it. I say this as an european, who not that long ago switched from a national currency to an european one. Back then, many people were scared of the very same thing, but it really didn't take long for people to adapt. I guess it would be pretty much the same for any physical unit relevant for people's everyday lives.

Re:Metric Everywhere

[epp_b]

Not to mention movies like "the Green Kilometer" - doesn't have the same ring to it.

*ahem*

"The Green 1.6 Kilometres"

Re:Metric Everywhere

[QuoteMstr]

Indeed. I'm an American, but I'm familiar with SI units. If I tell a friend that something is about two meters long, he's surprised, but he understands what I mean. That goes for everyone. Even in the US, people intuitively grasp how much a liter is, how heavy a kilogram is, and how long a kilometer is. We seem to have more trouble with temperature and speed though. I'm still a little taken aback when I drive into Canada and see speed limits far higher than what I'm used to.

Re:In before...

[Anonymous Coward]

Another preemptive strike: for anyone planning to say Fahrenheit is better because you can think of it as "percentage of warm", I call b/s:

• Warm is subjective - one man's warm is another's cool, and yet another's hot
• You can't argue that the freezing point of water isn't cold - no-one would think of it as "32% of warm"
• Celsius is better because it maps directly to percentage of the temperature difference between phase changes at STP, which is not subjective
• Since we need to deal with temperatures for more than just weather and HVAC, Celsius is better, because it makes sense for lots of things. Cooking a stew? 85 degrees (almost boiling, but not quite). A roast? 160 degrees in a fan-forced oven. Meringue? At least 200 degrees - twice the boiling temperature of water. Soldering? A bit over three times boiling temperature (320 degrees). The Fahrenheit numbers don't make anywhere near as much sense.

Um, no one doesn't

[afabbro]

One has to wonder if this is another imperial/metric snafu.

Uh, why? Yes, NASA made that mistake once, ten+ years ago. Aren't there plenty of other mistake categories that are just as if not more likely?

Re:Um, no one doesn't

[Brett Buck]

Only allowing data to be stored in metric units would likely reduce the likelihood of such a mistake, but it would not eliminate it altogether.

            Unfortunately you are about 50 years too late. In the aerospace industry, virtually ALL the data about most components is already "stored" in conventional units, no Metric. Forcing it to all be converted to Metric just creates the problem you are trying to solve.

      BTW, the MRO incident may have *started* with a units conversion error, but the real flaw was with the lack of due dilligence. The trajectory was diverging for months, and the problem could have been detected and solved easily if the normal checks and balances were applied.

        Brett

Hubble

[MillionthMonkey]

The Hubble misfocusing problem wasn't due to English-metric stuff. A contractor was assembling an optical apparatus and was supposed to be adjusting the focal length to a point inside some hollow cylindrical cap with a hole bored in its center. When adjusting their eyepiece they missed the hole, and centered instead on a shiny point near the edge of the cap that was also reflecting laser light, because the paint had been scratched there. They couldn't get the focus knob to rotate far enough as they would need to get this paint scratch into focus, so they drove out to a hardware store, bought some flat washers, inserted them on the threaded rods holding up the laser, and elevated the focusing section out a bit so they could dial the focus length to properly get the length to the scratch right.

Not an issue

[pyrrhonist]

One has to wonder if this is another imperial/metric snafu.

Probably not. From the article:

The $27 million, Italian-built observation deck sports the biggest window ever flown in space. In all, there are seven windows that will offer 360-degree views.

The 11 astronauts aboard the shuttle-station complex opened the door Friday to the $380 million Tranquility, also made in Italy for the European Space Agency. The door leading from Tranquility into the observation deck was opened soon afterward, and that's when shuttle pilot Terry Virts and Kay Hire encountered the cover problem.

So, now even submitters aren't reading the article? Damn...

Re:In before...

[Anonymous Coward]

At least 200 degrees - twice the boiling temperature of water

Any thermodynamics guy will tell you that "twice the boiling temperature of water" is 473.15 C.

Problem fixed as of Sunday

[chelberg]

The problem has been fixed, it was interference by some bolts.

"Late Saturday, the space station's commander, Jeffrey Williams, reported that bolts seemed to be causing the interference. He removed all eight bolts, saying the clearance would be tight but that the cover likely would fit. It did, with some coaxing Sunday."

http://apnews.excite.com/article/20100214/D9DS3UOO1.html

This is already a solved problem

[ChrisCampbell47]

Even if this gets modded up to +5, it's going to be buried under a dozen pointless and irrelevant posts about imperial vs. metric ...

From the ISS Flight Director briefing on NASA TV at 1:30pm today:
http://www.space-multimedia.nl.eu.org/index.php?option=com_content&view=article&id=5693:sts-130-iss-flight-director-update-fd-7-8&catid=1:latest
[transcribing] "Crew was able to use their eyes and hands and gave good info on interference along with photos, Jeff has had a lot of hands on the hardware and he's given us the best info. His info allowed us to validate what he's seeing with our records on the ground. Actual interference is just a bolthead, that caused us to question our clearance analysis. We went back and looked at it since we don't want clearance issue when we install Cupola on nadir, and found that we have more clearance than originally expected."

From the Flight Day 8 "execute package" sent up around 3pm to the Endeavour astronauts:
( http://www.nasa.gov/pdf/426345main_FD08.pdf )
"Because of your excellent work in checking interferences, we are now comfortable with
proceeding with cupola depress and relocate today!!! Thanks so much!!!"

From the NASA TV schedule, Tuesday:
CUPOLA MLI REMOVAL 10:39 PM EST / 03:39 UTC

After that the windows can be opened, which is what we're all waiting for!

Inside Scoop

[Anonymous Coward]

I work for Boeing (the main contractors for the ISS) and the problem is that the cover will not retract over one of the CBM (common berthing mechanisms) where they wish to install the Cupola. It is actually no impact to Tranquility which is working wonderfully so far. This issue has at this time already been resolved and the Cupola is being relocated to this area, while PMA-3 (Pressurized Mating Adapter #3) is being relocated to where the Cupola used to be. This was done so that the Cupola could face the earth and create all those fantastic views everybody envisioned from the ISS, while being able to be launched in the shuttle payload bay.

Re:Mock ups

[maxume]

Step 1: Land ISS.
Step 2: Test Fit
Step 3: Spend 20 years and billions of dollars reorbiting ISS.

Re:In before...

[Anonymous Coward]

Celsius? Fahrenheit? Who gives a shit? Both are just based around some physical referents. Neither is inherently "better" than the other. Both are equally descriptive of temperature. The main "selling point" is really the number of other folks using one or the other. For that reason alone, I would choose Celsius since more people use it. (And no, I don't natively use Celsius as I was born in, and live in, the US.) Oh, and both are the same at -40.

Americans are just mental wimps

[bussdriver]

The rest the world has to deal with english, American technical terms, corporations, IP laws, military bases, a hysterical anti-terror crusade and occasionally our messed up measurement system. Yet Americans can't handle having to transition to metric because it would be too hard and too difficult. The greatest generation could have done it, but not the current ones - its beyond their abilities.

Legacy parts? live with it. Eventually, they stop being produced anyhow. It can take decades to move hardware but a ton of stuff can be moved quickly.

Bunch of wimps. I know, I live here.

Re:Screwup, but not an units problem...

[joh]

Every dimension was converted prior to doing anything else. There are 25.4 millimetres to the inch, or 2.54 microns per ten thousandth of an inch. Never, ever had a problem converting.

That's because, ironically, the inch now is DEFINED as being 25.4 millimetres, so a clean and exact conversion is no problem since the inch is already based on metric units. Saying "one inch" is just another way of saying "25.4 millimetres". Other units are less clean and exact.