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Old 3rd June 2004 | 20:51
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Aim High
 
Joined: Nov 2001
Posts: 60
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From: London
The great circle bearing of position F longitude 24E from position 27N 8W measured at longitude 8E is 084T
The great circle bearing of E from F, measured at F is 272t

What is the bearing of F from E measured at E and what latitude
is F??

Convergency has changed by 8 degrees in the last third of dlong from 8E to 16E. So going back towards E decrease the GC track by two lots of 8 degrees from 264 (this number came from the reciprocal of 084).
264 - 8 - 8 = 248.
This is your Initial GC track.

Convergency = dlong x sin mlat
Convergency (IGC plus or minus FGC) = dlong x sin mlat
272 - 248 = 24 x sin mlat
24 = 24 x sin mlat
1 = sin mlat
Since sin 90 = 1, the mean lat is the pole!
for that to happen the other lat must be 27 N also

What a question! Not in the exam I hope.
Someonelse check my logic as well please
Aim High is offline