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Old 20th March 2004 | 18:22
  #19 (permalink)  
Tinstaafl
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Joined: Dec 1998
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From: Escapee from Ultima Thule
If you can count to 4 (or 5) & can measure a distance on a chart then you can do 1:60 very quickly & easily. To get the track error, for each n.m. off track:

if your distance run = 60nm -ish then multiply dist. off x 1 eg run 65 nm & 3 nm off track then track error = 3 deg

if dist run = 30 or so nm then dist. off x 2 eg 35 nm run & 3nm off track then T.E. = 6 deg ie 2 x 3

if dist run = 20-ish then dist off x 3. eg 22 nm run, 3 nm off, T.E. = 9 deg.

if dist run = 15 then dist off x 4.

if dist run ~45 then dist off x 1.5 ie add half the dist off to itself eg 48 nm run & 6 nm off track then T.E. = 6 + (half of 6) = 9 deg.

If you adjust hdg by the amount worked out above you'll parallel track - not always a bad thing.

If you want to close track at some point you can either double the T.E. worked out above and then you'll close track in the same time & same distance as it took to get off track, or pick a point ahead where you'd like to close track & do another 1:60. This time use the dist to go to get to that point on track instead of the distance run.

I prefer 1:60 for its no-brainer simplicity (ie remember 1 to 4 and multiply) and its flexibility to parallel or close track.
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