Notar520AC
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Knots

Sat Oct 06, 2001 6:32 am

Just a quick answer please- how many mph is a knot? Is there a conversion formula?
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apuneger
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RE: Knots

Sat Oct 06, 2001 6:47 am

A knot is defined as follows (if I remember well):

If you travel one nautical mile per hour, your speed is exactly one knot.

Therefor, one knot is one nautical mile per hour.

I don't know how many statue miles that is, or how do you call that? However, I do know that it's about 1.5 kilometer, so one knot is more than one statue mile per hour.

Ivan

Plz correct me if I'm wrong
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777236ER
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RE: Knots

Sat Oct 06, 2001 6:49 am

Knot to MPH x1.1515

MPH to Knot x0.8684


Yeah, a knot is one nautical mile per hour
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777236ER
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RE: Knots

Sat Oct 06, 2001 7:00 am

Oh my god, i just realised i know that by heart. That's it, i'm committing myself now.
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Notar520AC
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RE: Knots

Sat Oct 06, 2001 7:24 am

Gracias.
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Jet-A gasguy
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RE: Knots

Sat Oct 06, 2001 7:37 am

Notar520AC,

hey buddy, how ya doin? Been flyin the NOTAR lately?

 Smile
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timz
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RE: Knots

Sat Oct 06, 2001 12:17 pm

In the past there have been slightly-different definitions of the nautical mile, but it's now supposed to be 1852 meters exactly, while the statute mile is 1609.344 meters exactly.
 
lapa_saab340
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RE: Knots

Sat Oct 06, 2001 8:04 pm

Notar, if you want to roughly convert knots to mph and don't feel like using a calculator, you can do this:

Say your speed in knots is 160. Divide by ten (and get 16) and add it to your original to get 176mph. This gives you a rough estimate.
If you want a more exact answer, you do a little more math, just divide that 16 by 2, and add it as well.

So you have 160+16+8=184mph

The same applies if you want to convert mph to knots, except instead of adding to your mph speed, you subtract.

 
TAA_Airbus
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RE: Knots

Sat Oct 06, 2001 9:13 pm

For those of you that dont know, which seems to be everyone otherwise it would of been said already, the nautical mile was derived from 1 minute of longitude on the equator.

Therefore 1' = 1nm

However, as far as conversions go, As I am unaware of the international standard for the radius of the earth at the equator, I cant work out what 1nm is in kms or St.miles
 
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VirginFlyer
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RE: Knots

Sat Oct 06, 2001 9:25 pm

Um, I have always found these good:
Nautical->Statute (knot->mph): Divide by 8, multiply by 9
Statute->Nautical (mph->knot: Divide by 9, multiply by 8
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timz
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RE: Knots

Sat Oct 06, 2001 11:01 pm

The reason there have been various nautical miles in the past is the fact that the earth isn't spherical. WGS84 assumes the radius of the equator is 6378137 meters exactly, which makes a minute of longitude at the equator about 1855.325 meters. But a minute of latitude is 1842.905 meters at the equator and 1861.566 at the poles-- so presumably the now-official 1852-meter nautical mile is just a semi-arbitrary semi-average.
 
Boeing Nut
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RE: Knots

Sat Oct 06, 2001 11:05 pm

One statue mile - 5,280 ft.

One nautical mile - 6,000 ft.
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johnnybgoode
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RE: Knots

Sun Oct 07, 2001 2:09 am

pretty simple:

say you´ve got 200 knots, take 2 times and then minus 10%.
so that´s 200x2=400 400-40=360

200kts= ~360mph

rgds
daniel
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