Q1. 1. On a Polar Stereographic chart, the initial great circle course from A 70°N 060°W to B 70°N 060°E is approximate:
030° (T) – NH Polar Chart. A(60W) to B(60E) is Eastbound (across 000). dLong = 120. Isosceles triangle P-A-B. Angle P=120. Angles A&B = (180-120)/2 = 30. Track measured from True North (Meridian). At A, North is towards Pole. Track A to B is 030°.
Q2. 2. On a Polar Stereographic chart, the great circle course from A (70°N 060°W) to B (70°N 060°E) on arrival at B is approximate:
150° (T) – Symmetry with Q1. Angle at B inside triangle is 30°. Course is measured clockwise from North. Arrival direction is SE. 180 – 30 = 150°.
Q3. 3. On a polar stereographic projection chart showing the South Pole, a straight line joins position A (70°S 065°E) to position B (70°S 025°W). The true course on departure from position A is approximate:
225° – SH Chart. A(65E) to B(25W) is Westbound. dLong = 90. Isosceles triangle. Angle P=90. Base angles=45. Track measured from True North. At A, North is away from Pole. Path A->B is West (Left). Angle between North and Path is 180 (South) + 45? No. Standard calc: Initial Grid = 270 (West). Earth Conv = 1 * dLong? No. Geometry: Meridian A is 65E. North is Up (Away). Path is ‘Left’ & ‘Down’ relative to grid? Simpler: Westbound SH Track Increases? No, Westbound SH Increases. Vertex is midway? 65E to 25W. Midpoint 20E. Vertex Track 270. A is 45 deg East of Vertex. Track A = 270 – 45 = 225.
Q4. 4. On a polar stereographic projection chart showing the north Pole, a straight line joins position A (70°N 065°E) to position B (70°N 025°W). The true course on departure from position B is approximate:
045° – NH Chart. Departure from B(25W) to A(65E). Eastbound. dLong=90. Vertex midway 20E. Track Vertex 090. B is 45 deg West of Vertex. NH East Track Increases. Track B = 90 – 45 = 45.
Q5. 2.1>>On a Polar Stereographic map, a line is drawn from position A (70N 102W) to position B (80N 006E). The point of highest latitude along this line occurs at 035W. What is the initial straight-line track angle from A to B, measured at A?
23 – NH Eastbound. Vertex 035W (Track 090). A is 102W. dLong A-V = 67. A is West of V (Before). Track A < 90. 90 – 67 = 23.
Q6. 2.2> On a Polar Stereographic map, a line is drawn from position A (75N 100W) to position B (80N 010E). The point of highest latitude along this line occurs at 040W. What is the straight-line track Joining A to B, measured at B?
140 – NH Eastbound. Vertex 040W (Track 090). B is 010E. dLong V-B = 50. B is East of V (After). Track B > 90. 90 + 50 = 140.
Q7. 2.3>> On a Polar Stereographic map, a line is drawn from position A (70N 50W) to position B (80N 060E). The point of highest latitude along this line occurs at 035E. What is the initial straight-line track angle from A to B, measured at A?
5 – NH Eastbound. Vertex 035E (Track 090). A is 50W. dLong A-V = 50+35=85. A is West of V (Before). Track A = 90 – 85 = 5.
Q8. 2.4>> On a Polar Stereographic map, a line is drawn from position A (70N 20E) to position B (80N 060E). The point of highest latitude along this line occurs at 035E. What is the initial straight-line track from B to A.?
295 – NH Westbound (B->A). Vertex 035E (Track 270). B is 060E. dLong B-V = 25. B is East of V (Before). NH Westbound Track Decreases. Initial > Final? No. NH West: Track Decreases from 270+ to 270-. Start (B) is 270+25=295. End (A) is 270-15=255. Answer 295.