The position A (75°N, 34°E) of an aircraft and the position B (75°N, 50°E) of an NDB station are plotted on a polar stereographic chart projection and are connected with a straight line. Determine the true bearing from position B to position A, given:
Magnetic variation at position A: 32°W
Magnetic variation at position B: 60°W
Refer to figure.
We can create a triangle made up by the North Pole (P), position A and position B.
The angle at P will be the difference between longitude of position B and position A.
-
Postion B = 50º; Position A = 34º
Angle at P = 50º - 34º = 16º
Position A and B are located at the same latitude, which means: OA = OB. Therefore, the triangle APB is isosceles; and Angle at A = Angle at B.
The sum of angles of a triangle equals 180º. Consequently, Angle A and Angle B:
-
180º - 16º = 164º
164º / 2 = 82º
True bearing from position B to position A equals the angle measured clockwise from the True North at position B to the line connecting B to A. Angle at B = 82º. Therefore, True bearing from position B to position A = 360º - 82º = 278º
Your Notes (not visible to others)
This question has appeared on the real examination, you can find the related countries below.
-
Spain4
-
Belgium1
-
Czech Republic1
-
France1
-
Ireland1
-
Serbia1
Use Keyboard Shortcuts
