Why miles or km on land but on sea or air it's nautical miles?

Question

Please don't paste the wikipedia article on this. I've read it already and I can't make heads or tails of it. Can you explain it like you are talking to a 10-year-old? Much appreciation!

More info: Please don't worry about explaining the history of the nautical mile or that "navigational charts use nautical miles, so that's why!"

My question is why are there different units for cars than boats or planes. I am interested in why we don't use nautical miles when driving, or why planes don't use miles. Thanky.

Answer 1

Okay, my 10-year-old friend, let's explain the two measurement systems this way:

Knowing how to measure distances on land is very important for marching armies. They would count paces. (When marching Left-Right-Left-Right... a 'pace' is from Left to the next Left). One thousand paces. In Latin, "mille" means one thousand. If you walk and count a thousand paces you will have covered about a mile.

At sea, we have no paces or steps to count. Once sailors figured out that the world was basically a round ball, they wanted an easy way to navigate. If you slice the ball along the equator, you'll expose a circle. We divide that circle into 360 degrees, and we divide each degree into 60 "minutes" (and yes, we can even divide each minute into 60 seconds if we want). One minute of a degree at the equator is the nautical mile. It just happens to be a little bigger than a terrestrial mile. Too bad for those who wish otherwise.

Hope thats real clear now. Have a nice day.

Answer 2

It is because 1 nautical mile is greater than 1 Mile or 1 km. Aeroplanes and ships generally have to travel huge distances often across continents and oceans hence they do not require distances that are of a short interval. it might be a bit too confusing to use large
numbers. Also at such large distances the latitudes and longitudes play a vital role in finding your way. Now 1 nautical mile is actually defined as 1/60th of 1 longitude at the equator.
This becomes an additional advantage for navigating at sea or by air where there are virtually no stationary landmarks to tell you where you actually are.
In land the landmarks( cities, towns, villages, physical features, geographical marks) are more prominent and they remain stationary. Which makes it more convenient to calculate distances by using a relatively smaller unit i.e. mile or km. since the distance between to landmarks in land is less when compared to that of air or water. Hence a nautical mile would be a bit too inconvenient to be used,so the
use miles and kms. Moreover roadways or railways can hardly cross a continent and never a ocean. Hence it s now a comman practise to use miles or km on land. Just think about it! Why do astronomers calculate distances in Light Years and not in miles or kilometers. Because if they would be doing that then they would run out of paper even before finishing the sentence! and I am in no way exaggerating my statement!

Answer 3

A statute mile is an arbitrary distance = 5280 feet. A kilometer is supposed to be 1/10,000 of the distance from the equator to the north pole it's off because the distance wasn't known too well when the metric system was invented.) A nautica mile is 1 60th of the length of a degree of longitude at the equator. That makes laying out courses on a chart very easy. A knot is not really a distance, it's a speed = 1 nautical mile per hour - and it does come from letting a line with knots in it run over the stern of a ship. the expression"knots per hour" grates on a sailor's ear. It's very pleonastic.

Answer 4

Look at it this way. We used the latitudes and longitudes to calculate distance. A nautical mile is a bit longer than a regular mile because on land the surface is so irregular that we decided to consider the land flat for measuring purposes. But when you measure a mile on a flat map and mark the distance, and then you measure the same area on a round globe, the round globe will show a longer distance between those points because the earth is round. So mile are drawn on a flat map but on the water they end up longer because of the curvature of the earth.

Answer 5

I do use nautical miles and knots when driving a car, but I'm just silly with my GPS.

Some airplanes (especially small) use MPH for indicated airspeed, instead of knots.

My old boat had MPH on it's speedometer.

Airplanes in russia and china use meters for altitude instead of feet.

There is no rhyme or reason. It's arbitrary and traditional, like most things in life!

Then again, when flying an airplane, it's easier to say "two hundred knots" rather than "two hundred thirty miles per hour" or "three hundred seventy one kilometers per hour". perhaps that has something to do with it, at least in aviation, and regarding air traffic control.

Answer 6

a statute mile is 5280 feet and a nautical mile is 6000 feet . I think the king of England established the statute mile and mariners used the nautical mile as it was commonly used . It was a way of distinguishing the difference between land and sea. when viewing a map.

Answer 7

And regarding air travel--the military needed a consistency between the Navy and the other branches--military trained most of the pilots so nautical miles stuck.

Answer 8

A nautical mile isn't precisely one minute of arc around the earth, besides the undeniable fact that it is close. a million nautical mile = 1852.000 meters (precisely, by definition) a million minute of arc = 1852.216 meters on a line of longitude a million statute mile = 5280 survey ft = 1609.347219 meters a million global mile = 5280 ft = 1609.344 meters (precisely). (The nautical mile replaced into defined as 1852 meters decrease back in 1929.) (The "foot" replaced into defined a tiny bit in 1959. The "survey" foot and mile nevertheless use the single definitions.)

Answer 9

It originated with sailors estimating their speed by dropping a float attached to a knotted rope into the water and allowing it to play out astern.The faster the ship went the more knots were played out in a fixed time.This calculation was then in more recent times converted from knots to nautical miles.

Answer 10

Nautical miles is the division of the earth. It is length based and is equally spaced into latitude and longitude.

Miles or kilometres is a distance covered in a matter of time, which gets you your speed.