I can generally do most great circle questions by drawing out a diagram depending on what hemisphere were in, drawing the straight line as a rhumb line and the great circle towards the nearest pole. However i seem to be having trouble with great circle bearings, and i dont know if you need to draw a different diagram to help.
Most great circle questions involve convergency, which i can never figure out to add or take away, that's the reason for me drawing the diagram as described above, but do i need to draw a different type of diagram for different questions?
There are 2 questions i am struggling with at the minute, which i can't figure out at all.
1) The great circle bearing of position B from position A in the northern hemisphere is 040 degrees. If Conversion Angle is 4 degrees, what is the great circle bearing of A from B?
For this question i take the reciprical of 040, which is 220 degrees, i know CA is 4 degrees so i add it on to give 224 degrees but the answer states that it is actually 228 degrees, can anyone explain how they get this?
2) The great circle bearing from A (70S 030W) to B (70S 060E) is approximately?
For this question i figure out that the rhumb line track is going to be 090 and the conversion angle is 42 degrees, but looking at my drawing it tells me to take the conversion angle away, but the answer is 132 degrees implying i have to add it on, so i am getting very confused. Can anyone explain the error in my ways?
Thank You
