124 THE DEVELOPMENT OF WEAPONS SYSTEM REQUIREMENTS 



50 

 ^^ 40 

 - 30 

 ■ o, 20 



10 



-1200 

 -1100 

 -1000 

 -900 

 -800 

 -700 



^ 60 



t 50 

 o 



-S 40 



^ 30 

 o 



£ 20 



^ 10 



:110° 



-1.0 

 -0.8 o 

 -0.6 ^ 



X) 



-0.4 I 

 -0.2 



10 20 30 40 



TIME TO GO (seconds) 



50 



60 



:110 



20 30 40 



TIME TO GO (seconds^ 



50 



-1.0 

 -2.0 

 -3.0 

 -4.0' 

 -5.0 



60 



20 30 40 



TIME TO GO (seconds) 



50 



60 



Fig. 2-45 Dynamic Variation of Lead Collision Fire Control Parameters. 



measurement errors affect the firing time and the steering error as calculated 

 in the fire-control computer by Equations 2-59 through 2-62. 



Because dynamic lag errors are predictable, it is theoretically possible 

 to eliminate them entirely by suitably clever design. However, the more 

 usual approach is to limit the magnitude of these errors to some finite value. 

 As a general rule of thumb, it is desirable that the total value of the predict- 

 able bias error contribution obey the following inequality: 



B <yj2(r (2-63) 



where B = total predictable bias error 



<j == standard deviation of the total random error. 



