[harshpotatoes]

Could you imagine Boeing/lockheed/GM/some some oil company or any other manufacturer going up to their stockholders and saying: "This next year, profits will be significantly reduced as we replace every piece of equipment we own, replace every 1/4-20 screw with an M5, and redesign every aircraft/automobile/widget to meet new metric specifications"

[venus]

I suppose it'd be better than being Boeing and going in front of your stockholders to explain why your marketshare is radically down because you refused to conform to the measurement system 95% of your customers are using.

It's a non-question anyway. Boeing planes already report fuel load in litres. Funnily enough, flight levels are internationally represented in feet (well, 100-feet) so there's a "win" for you. Also, ground speed is measured in knots!

[teamonkey]

The knot isn't quite as arbitrary as most imperial measures.

1 knot = 1 nautical mile/hour

1 nautical mile ~= the distance travelled by someone at the equator in one minute due to the Earth's rotation

Since navigation at sea was strongly dependent on the position of the sun and stars, it makes sense to use a unit of speed that makes your calculations easier.

Even for modern navigation it makes sense to use a unit of measurement based on the circumference of the great circle surrounding the Earth.

[ScottBurson]

> 1 nautical mile ~= the distance travelled by someone at the equator in one minute due to the Earth's rotation

No. It's approximately one minute of arc, that is, 1/60 of one degree.

In fact the speed of the earth's rotation at the equator is more like 15 nautical miles per minute.

[teamonkey]

Yes, you're right of course. The Earth rotates through 15 arcminutes in 1 minute.

[nemo]

Boeing has run into occasional problems by holding to imperial rather than moving to metric and these will only get worse, esp. with their model of using vendors around the globe. In aerospace it's ugly since imperial is so entrenched, but other industries have retooled, there are examples to learn from for efficient transitions.

GM already went metric.

Lockheed destroyed a half-billon dollar space mission by clinging to imperial.

[ScottBurson]

> Lockheed destroyed a half-billon dollar space mission by clinging to imperial.

If anyone wants more details: http://en.wikipedia.org/wiki/Mars_Climate_Orbiter

[XorNot]

Aerospace is the origin of the insanity which is modern pipe thread specifications. The metric version is still in inches, but whatever 1/8" means, the pipe it goes in no obvious dimension represents that size.

Like, I know there is a system and calculations behind it, but they are in no way friendly to any user.

[jahewson]

There are costs to sticking with the imperial system. Non-US buyers want metric products which fit with their existing tooling. The factories of the world want all-metric manufacturing, which reduces costs. Error from unit conversion is a real problem.

Designing new products in metric wouldn't require old products to be replaced with imperial. Each product line has it's own special repair kit, spare parts, already. It's not like the suppliers who actually make parts aren't equipped to do metric if they're selling parts worldwide.

The UK went metric in the 1960s and it managed just fine, so there's no reason why it can't be done. Some pragmatism can be involved, for example road signs in the UK are still in miles, and one can still buy a pint of milk or beer (though the latter are technically labelled and sold in millilitres).

A move to metric wouldn't dictate the internal practices of a company like Lockheed, they could still require their suppliers to build parts in inches (even if that means that formally they purchase 2.6234cm sized screws or similar) and they can continue to do everything in inches. Not that they'd want to.

[rmc]

Ireland also went metric. We switched road speed limits in 2006ish, so all the signs say "km/hr" so you don't forget (it's also helpful to tell when you cross the border unto hr uk). Beer is sold in 568ml (1 pint), but milk is sold in litres.

[stephen_g]

It's quite interesting in Australia that you buy a pint of beer if it's in a glass (or a pot, which is much smaller or schooner, pronounced 'skooner', which is a bit smaller), but bottles are never sold as imperial are generally 375mL.

[jarek]

In England cans of cider are 500 mL. Honestly I don't really think a pint is a unit (except for old people buying milk?), it's a descriptor like "a glass" or "a pitcher" that just happens to have a legally required size. I have an idea roughly how much a pint is but I wouldn't requisition three pints of hydrofluoric acid.

[kalleboo]

Could you imagine Boeing/lockheed/GM/some some oil company or any other manufacturer going up to their stockholders and saying: "We're going to avoid the metric that most parts are manufactured in (economies of scale) and most of our outsourcing partners are familiar with (risk of errors) and instead stick to customary measures because a foot feels 'more natural'"

[rakoo]

It's not like the metric system was invented yesterday and will vanish tommorrow. Change doesn't have to be instantaneous, it can be gradual over the years (and, as the article pointed out, already is)

[harshpotatoes]

I agree that things won't change instantaneously, but I also don't think change will happen or even could happen as quickly as most of the talk on the internet thinks it should.

These articles make the rounds on the internet every few months, which gives the impression change should happen quickly. But, given the enormous costs that exist to switch over, I think it's more likely we'll see a gradual change over our lifetime.

[_delirium]

Also, switching to metric units for measurement doesn't mean you have to switch the physical size of parts: there is nothing in the metric system requiring that you use round numbers in manufacturing. Canadian engineering, for a mixture of historical reasons and ties to the U.S., measures in metric but often has parts with suspicious sizes like 101.6mm.

[kalleboo]

> Change doesn't have to be instantaneous, it can be gradual over the years

As an example, NASA is partially-metric, partially-imperial. Of course, they have that famous failure attributed to mixing units...

[spiritplumber]

I did a bit of work at NASA a couple years back, they wanted everything in millimeters (possibly to deal with the aftermath of that incident). Everything. Even antenna lengths.

[watchdogtimer]

I work in manufacturing, and one thing I've noticed here in the U.S. is that metric hardware (nuts, bolts, etc.) is consistently more expensive than comparable-sized imperial hardware. I've never received a satisfactory explanation why.

[UnoriginalGuy]

As opposed to losing money BECAUSE they're using imperial as happened here: http://metricviews.org.uk/2007/11/boeing787-grounded/