Torpx means that if, after adding or subtracting 90, if your result is greater than 360, then subtract 360, but if the result is less than zero (instead of 360 as stated), then add 360.
Course = 300 from port, 300 + 90 = 390. Result is greater than 360, so subtract 360 to give steering course of 30.
Course = 45 from starboad, 45 - 90 = -45, so add 360 to get steering course of 315.
__________________
--------------------------------
This space left intentionally blank.
|