Primarily for general aviation discussion, but other aviation topics are also welcome.
By BoeingBoy
#1893884
You place the edge along the track you want to fly and read the desired bearing at the twelve o'clock position of the compass rose.
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By David Wood
FLYER Club Member  FLYER Club Member
#1893885
It's designed to enable you to make rapid measurements of distance and track from your current position (centre of the dial) to somewhere else. You read off the range from the scale and read off the track in degrees (true) from the number at the top of the dial against a convenient grid line.

Personally I don't use them.
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By PeteSpencer
FLYER Club Member  FLYER Club Member
#1893887
Dusty_B wrote:Also used against VOR roses. Great for cross-cuts.


Remembering that VORs are magnetic which ATM is virtually the same as True
By ian_737
#1893912
Gotcha, thanks all. I thought it could be used instead of a standard plotter but now see it's an additional tool. Cheers!
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By Dusty_B
FLYER Club Member  FLYER Club Member
#1894023
It can certainly be used instead of a huge square protractor, but the increments are too large to provide any accuracy if you are taking it seriously.
A far better option is the Pooley's RNP1. It combines all three tools - square protractor (in two halves), ruler, and radial/distance plotter.
By Lefty
FLYER Club Member  FLYER Club Member
#1894027
Dusty_B wrote:It can certainly be used instead of a huge square protractor, but the increments are too large to provide any accuracy if you are taking it seriously.
A far better option is the Pooley's RNP1. It combines all three tools - square protractor (in two halves), ruler, and radial/distance plotter.


I’m not sure how serious you want it to be? The RNP2 is just fine for all normal flight planning and especially for inflight diversions. It is just easy to use, and few pilots can fly to +/- 1 degree.

If sitting a CAA nav exam where you need to be 1 degree accurate, then yes, the full sized square protractor is what you need. (Not the RNP1)
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