1. Get on a
Collision course with the Target.
Constant bearing plus closing Range = Collision Course.
Adjust your own course and/or speed.
2. Formula:
Own Speed : Sin Target AoB : : Target Speed : Sin Target Bearing
3. If you have a sliderule hidden in the desk drawer, dust it off, this method is extreme fast.
Here are two views, one is of a regular sliderule, and the second is a circular sliderule. The logrithmic characteristic and function of sliderules makes this an easy problem. (apologies for the bit of blurriness)
Here's the same thing with a sliderule that I made from heavy card stock and covered in clear plastic at Kinko's used with the original Silent Hunter.
One side is sliderule the other is whiz-wheel.
Here's a pic of a rare WWII Uboat whiz-wheel
