INTERCEPT PROCEDURES TEXTBOOK
In the previous examples the final collision course has always been a cardinal heading (a
heading that ends in a zero, i.e., 240°, 050°, 120°, etc). In all subsequent problems, the collision
course will still be a cardinal heading. This is the result of rounding.
Before the bogey bearing or angle off is used to make a collision course correction, it is first
rounded off to the nearest five or zero using the following scale:
0, 1, or 2 rounds to 0
rounds to 5
8, 9, or 0 rounds to 0
The bogey heading, and hence the bogey reciprocal, is always a cardinal heading in this
syllabus. Setting AO equal to but opposite in direction to the TA will always result in a cardinal
heading for a collision course. If the RIO/WSO comes up with a collision course that does not
end in a zero, then the answer must be wrong.
Rounding permits faster math for faster CCC's and causes fewer arithmetic errors. It is the
weapons officer's responsibility to round the bogey bearing call from GCI or the AO from the