GC concave to PoO, RL concave to pole of projection. Constant of the cone, n=Sin(PoO)
Post 327
Originally Posted by captaa
2) A Lambert conformal conic chart has a constant of the cone of 0.75.The initial course of a straight line track drawn on this chart from A (40°N 050°W) to B is 043°(T) at A; course at B is 055°(T).What is the longitude of B?
A 36°W B 38°W C 41°W D 34°W
Post 328
Originally Posted by 3greens 1inthemirror
2) conv = 12 deHdg tg (55-43)
conv = dlong x sin lat
since constant of cone is 0.75 , sin lat = 0.75
Thus, dlong = 12/0.75 = 16 deg
( since course is 043 which means the a/c is moving east)
50 W - 16 = 34 W
Great Circle usually appears concave to the parallel of origin. Nothing wrong with the answer though.
Fig.9.5 Pg 96 GSP Navigation RB Underdown & Tony Palmer
Edit: Found this on another page, so disregard the above.
Although great circles in fact appear as curves on the chart, for practical purposes they can be taken to be straight lines. This is because their curvature is slight.
Last edited by aditya104; 10th May 2012 at 13:19.
Reason: For practical purposes, GC straight line on a Lambert's