Metric vs Imperial poll

[rxcomposite]

I am currently working as a surveyor working with different ships from different nationalities and ships built from different parts of the world.

Even the builders are confused. The trim and stability booklet/tank calibration tables I see are sometimes in metric (soundings) with US gallons (volume), or measurements are in inch but reports have to be in metric ton. To top it all, tanks are filled here using Imperial Gallon which is larger than the US gallon.

In trying to please the world, they also got confused.

[murdomack]

Given that we will all have our preferences, there is nothing to fear in learning to work with either system. I have had to teach the Imperial system to people brought up in Metric and they all manage fine. Lots of us 'Imperial" people had to learn the metric system back in the 70's and most managed it.

The problems start when someone gets drawings in one system and starts converting to the other. This is a recipe for errors, it is best to stick with the one you are given.

[ancient kayaker]

Originally Posted by murdomack

Given that we will all have our preferences, there is nothing to fear in learning to work with either system ... The problems start when someone gets drawings in one system and starts converting to the other. This is a recipe for errors, it is best to stick with the one you are given.

Conversion is where the problem begins especially where there is confusion. The biggest problem is when a person is not familiar with one of the systems being used; the automatic mental check "is that reasonable" doesn't work then, so errors don't get picked up. Conversion should be done in a computer if it's really important.

Originally Posted by rxcomposite

I am currently working as a surveyor working with different ships from different nationalities and ships built from different parts of the world.

Even the builders are confused. The trim and stability booklet/tank calibration tables I see are sometimes in metric (soundings) with US gallons (volume), or measurements are in inch but reports have to be in metric ton. To top it all, tanks are filled here using Imperial Gallon which is larger than the US gallon.

In trying to please the world, they also got confused.

Now that is a recipe for disaster! There was a case of a new plane with metric instruments that needed refuelling. The fuelling truck operator had to do a double conversion to get from what the truck showed him (volume) to what the airport worked with (imperial weight) and from there to the metric weight that the aircraft instruments reported. The aircrew also was not familiar with metric so they took off with N lb instead of N kg. They didn't get far; miraculously the pilot managed to land the big glider at a disused airfield.

[pamarine]

Metric with Knots and Nautical Miles.

[ancient kayaker]

Originally Posted by pamarine

Metric with Knots and Nautical Miles.

Nautical miles, cables (1/10 nm), fathoms (1/1000 nm) already exist. Introduce the nautical inch (1/100 fathom or 0.7296 imperial inches), and redefine the furlong (1/10 nm), then we would finally have a truly logical and consistent system. Might cause a little bit of an upset of course, but no more than the SI did.

[hoytedow]

That nautical inch thing would be quite useful, especially when braggin' meself up to the fairer ones.

[pamarine]

Originally Posted by ancient kayaker

Nautical miles, cables (1/10 nm), fathoms (1/1000 nm) already exist. Introduce the nautical inch (1/100 fathom or 0.7296 imperial inches), and redefine the furlong (1/10 nm), then we would finally have a truly logical and consistent system. Might cause a little bit of an upset of course, but no more than the SI did.

Not a bad idea, especially since it's all based off natural measures (well, degrees). But I'm confused why we need both furlongs and cables to be 1/10 nm?

[ancient kayaker]

Oops! 1 cable = 1/10 (nautical) furlong = 1/10 nm. But you knew that already!

[hoytedow]

I'll say po-tay-to, and you say po-tah-to.

[ancient kayaker]

Soon one of the pro-metrics will jump in and attempt to destroy the Nautical Unit Mile (NUM) system concept with faultless logic. There is something about the metric system that nums the humour centers of the brain.

[rambo!]

Looking at wiki: one num in metric (agreed in 1929) is 1852 m, in US it was defined as 1853,248 m (6080 US feet) and in UK 1853,184 m (6080 UK feet).

One inch was (among other anecdotes) defined as a "the with of a normal sized mans thumb at the base of the nail".

A sea mile (nautical mile) is at the equator 1842,9 m and 1861,7 m at the poles, the mean is 1852,3m. The international nautical mile was choosen to be the integer number of meters closest to the mean sea mile.

So its not a question of how you chose to measure, its all about how you agree upon how to convert between different systems.

So to us metric´s there is a lot of humour and wierdness in the imperial system, but both seems to work pretty well, so maybe we shall try to keep this little obscurity as long as possible.

[bjviking]

Option 2 for me.

[ancient kayaker]

pouce (fr), inch, thumb

[maxsalgado]

Metris is deffinately the way to go, I have built boats in imperial and worked in one metric and it is so much sompler, altough imperial units have something metric doest, that is that it is so much easier to estimate thickness of up to 5 inches in imperial than in metric, I dont know I just think its more of a real worlf unit, to bad the had to go and make 12 = 1 and all that nonsense

[ancient kayaker]

Historical reasons probably. 1 inch - width of thumb, 1 foot = length of foot, 1 yard = length of stride or nose to tip of finger with arm held to one side, as when measuring cloth. Later someone set standards and it just came out with 3 feet to the yard and 12 inches to the foot.

SI was set up using the base of 10, which is the number of fingers careful workers generally have. More happenstance.

What I never understood was why the metric folk did not, while they were at it, decimalise circular measure (degrees) and time units.