Chapter 3 — BEARINGS AND MOTION 



OWN SHIP 



Figure 3-13. 



71.8 

 Solving target aspect. 



Imagine that you ai'e on board a submarine 

 looking at an approaching destroyer. The rela- 

 tive bearing of the destroyer is 090°, which 

 indicates it is approaching on the submarine's 

 starboard beam. As vievi^ed from the destroyer, 

 the submeirine's target angle is 090°, because 

 target angle is the relative bearing of the ship 

 from the target, measured in the horizontal 

 plane from the bow of the target clockwise 

 from 000° to 360°. Like target aspect, target 

 angle depends on the target's heading. When 



the submarine changes course, tai'get angle 

 changes accordingly. 



Figure 3-14 illustrates several target angles. 

 Also shown are angles on the bow (discussed 

 later) and related doppler. Notice that no matter 

 in which direction the ship is heading, the 

 course of the submarine governs target angle. 



You may be curious why target aspect is so 

 important when target angle provides more accu- 

 rate information. Aspect is given as a general 

 indication and can be reported after only four 



31 



