Notar520AC
Topic Author
Posts: 1517
Joined: Sat Jul 21, 2001 6:53 am

Knots

Sat Oct 06, 2001 6:32 am

Just a quick answer please- how many mph is a knot? Is there a conversion formula?
BMW - The Ultimate Driving Machine
 
User avatar
apuneger
Posts: 2964
Joined: Fri Sep 08, 2000 2:43 pm

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
Ivan Coninx - Brussels Aviation Photography
 
777236ER
Posts: 12213
Joined: Sat Aug 18, 2001 7:10 am

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
Your bone's got a little machine
 
777236ER
Posts: 12213
Joined: Sat Aug 18, 2001 7:10 am

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.
Your bone's got a little machine
 
Notar520AC
Topic Author
Posts: 1517
Joined: Sat Jul 21, 2001 6:53 am

RE: Knots

Sat Oct 06, 2001 7:24 am

Gracias.
BMW - The Ultimate Driving Machine
 
Jet-A gasguy
Posts: 259
Joined: Sun Dec 24, 2000 4:04 pm

RE: Knots

Sat Oct 06, 2001 7:37 am

Notar520AC,

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

 Smile
Jet-A gasguy

Find a job you love, and you'll never work a day in your life.
 
timz
Posts: 6199
Joined: Fri Sep 17, 1999 7:43 am

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
Posts: 396
Joined: Tue Aug 07, 2001 8:42 pm

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
Posts: 491
Joined: Mon Nov 01, 1999 4:34 pm

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
 
User avatar
VirginFlyer
Posts: 4235
Joined: Sun Sep 10, 2000 12:27 pm

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
"So powerful is the light of unity that it can illuminate the whole earth." - Bahá'u'lláh
 
timz
Posts: 6199
Joined: Fri Sep 17, 1999 7:43 am

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
Posts: 5078
Joined: Fri Feb 23, 2001 2:42 am

RE: Knots

Sat Oct 06, 2001 11:05 pm

One statue mile - 5,280 ft.

One nautical mile - 6,000 ft.
I'm not a real aeronautical engineer, I just play one on Airliners.net.
 
johnnybgoode
Posts: 2144
Joined: Wed Jan 03, 2001 8:47 pm

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
If only pure sweetness was offered, why's this bitter taste left in my mouth.

Popular Searches On Airliners.net

Top Photos of Last:   24 Hours  •  48 Hours  •  7 Days  •  30 Days  •  180 Days  •  365 Days  •  All Time

Military Aircraft Every type from fighters to helicopters from air forces around the globe

Classic Airliners Props and jets from the good old days

Flight Decks Views from inside the cockpit

Aircraft Cabins Passenger cabin shots showing seat arrangements as well as cargo aircraft interior

Cargo Aircraft Pictures of great freighter aircraft

Government Aircraft Aircraft flying government officials

Helicopters Our large helicopter section. Both military and civil versions

Blimps / Airships Everything from the Goodyear blimp to the Zeppelin

Night Photos Beautiful shots taken while the sun is below the horizon

Accidents Accident, incident and crash related photos

Air to Air Photos taken by airborne photographers of airborne aircraft

Special Paint Schemes Aircraft painted in beautiful and original liveries

Airport Overviews Airport overviews from the air or ground

Tails and Winglets Tail and Winglet closeups with beautiful airline logos