OnCourse Software

Ray Lunning wrote:

I hope you don't include "knots" or "nautical miles" as part of a metric system...
Miles per hour or kilometers per hour I don't believe are ever used..
I am sure some one will prove me wrong.....

Yes, Ray, they do use kilometers per hour and and kilometers for distances And, meters per second for wind speed. There are still 360 degrees in a full circle though

By the way, in the 60s-70s many American made planes came from the factory with a MPH indicator installed..

Google up for example "russia metric system altitude" for a wealth of info if interested.

All IFR charts and navigation in the USA use "Nautical miles" and Knots which is a 'nautical mile' per hour...

Nautical miles is derived from nautical navigation..It is based on 360 degrees about the surface of the earth....As 1 second of arc on the earths surface represents one nautical mile.. (I am doing this from memory which has slowed).. It is a more logical way to measure distance on the earths surface as it has a direct relationship to the 360 degrees around the earths surface...

A nautical mile has no relationship to feet or meters..(it can be converted though)

True, early aircraft had airspeed indicators calibrated in miles/hour...My 1979 Cessna T210 airspeed indicator was in knots. All DME equipment gave distances in Nautical miles...

All my Jeppesen Low Enroute Charts and Approach charts are all printed in Nautical Miles... As Jeppesen publishes charts for the whole world I assume the whole world is published in nautical miles.. I guess Jeppesen can publish a "Russia or China" version...

I admit I can't speak for the whole world...

Ray Lunning

Correction: 1 degree = 60 nautical miles...Therefore 1 min of arc = 1 nautical mile..
360 degrees = 21600 nm = 24874.5 statute mi. at the equator..

1 nautical mile = 1.1516 statute mile...

Conclusion...Nautical miles are a world standard...

Nothing to do with feet or meters...

Ray Lunning

Ray Lunning wrote:

Conclusion...Nautical miles are a world standard...

Nothing to do with feet or meters...

Hi Ray

Not sure what the point is you are making, but a fact is that the countries mentioned do use the metric system in aviation.

That in itself has nothing to do with the other fact you're mentioning - NM, FT, and KTS are an ICAO standard (not a WORLD standard) and how they are derived from the dimensions of our globe.

-kyle

'Nuff said.. Not sure what this thread is trying to prove...
Also "nautical miles" have been around longer than the ICAO..

Mariners used a Sextant to determine longitude and latitude and nautical miles between points...

For now, I'll avoid Russia and China..

Last post on the subject.....

Ray Lunning wrote:

'Nuff said.. Not sure what this thread is trying to prove...
Also "nautical miles" have been around longer than the ICAO..

Mariners used a Sextant to determine longitude and latitude and nautical miles between points...

For now, I'll avoid Russia and China..

What is it trying to prove? Just read it from the top! Hardly trying to prove anything, but originally a PFE feature request from a user asking if altitudes be given in meters instead of feet when flying through certain territories, as in reality.

I'm not sure either what got you so defensive. No one is denying that nautical miles haven't been around longer than ICAO or anything of that sort. All I'm saying is that there are differences in systems between countries, just like the Americans have their altimeter in inches compared to QNH in the rest of the world - and that sure is modelled in PFE.

The altitude measurement system is no different from that. The russians, chinese and some other former soviet states use meters, kph and mps. Fact. Not better than the conventional system, maybe even worse (imho) but hey, they've decided to use that convention.

And since I'm now totally confused I'll put the request on my list and go back to bed!