APPENDIX D 



ANSWERS TO PROBLEMS 



ANSWER TO PROBLEM 1 



(1) standard compass : 



(2) Steering compass : 



(B) Place fore-and-aft magnets red ends aft. Place athwartships magnets red 

 ends to starboard. To correct D and E place spheres on athwartships axis and 

 slew about 17° clockwise. Move sphere to 15" postion. (See fig. 31, 33, and 

 ch. XVII.) 



(C) Slew binnacle 1.2° clockwise. Lower the fore-and-aft magnets to re- 

 move 7° E. deviation. Raise the athwartships magnets to remove 6° W. devia- 

 tion. Slew spheres about 28° counter-clockwise from athwartship axis and move 

 out to 15" to remove D of 4.9" W. and E of 3° W. (See figs. 31, 33, and ch. 

 XVII.) It must be remembered that in this problem the spheres at their 

 existing positions are correcting about 7" E. D error, thus making the total D 

 about 2° E. and E about 3° W. This indicates slewing 28° counter-clockwise and 

 a resultant quadrantal error of about 8.5°, which requires the 7" spheres at the 

 15" position. 



(D) (See summary of compass errors and adjustment) figure 19. 



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