Vlll 



FOREWORD 



sleep, diet, habitability, and combat strain 

 vary from one situation to another, but they 

 are always present to affect efficiency. Dial 

 designs that are desirable for the Field Artil- 

 lery may well find an important place on 

 shipboard equipment, and the limitations of 

 the human factor which have led to the use of 

 data transmitters and servo-mechanisms in 

 anti-aircraft fire might well be considered by 

 the Field Artillery, Even the principles of 

 psychological warfare which can be devel- 

 oped and turned against the civilian and 

 mihtary personnel of an enemy can be used 

 to develop countermeasures which will pro- 

 tect and enhance the morale of one's own 

 group. 



The utilization of the results derived from 

 scientific studies of the human factor in 

 World War II was frequently followed by an 

 increase in personnel efficiency of from 15% 

 to 35%. This was true in voice communica- 

 tion, in code training, in reading gun sights, 

 and in the firing of flexible guns on the B-29. 

 With a large military estabhshment, enor- 

 mous gains or losses in total man-hours hinge 

 upon correct decisions with reference to se- 

 lection and training. Equipment designed 

 without a nice regard for the capacities and 

 Hmitations of the human operator becomes a 

 long-continuing source of inefficient perform- 



ance.' This regard should be exercised dur- 

 ing initial concept and prehminary design 

 stages, if full benefit is to be reahzed. Too 

 often the expert in human engineering is con- 

 sulted at a time when only relatively minor 

 changes in design or function are possible. 

 On the other hand, in the relatively few cases 

 where the psychologist has been made a 

 member of the team of physical scientists, 

 engineers, tacticians, and educators, rapid 

 and significant progress has been made. In 

 1944 a distinguished Naval officer of engi- 

 neering could write as follows: "As a result 

 of such scientific apphcations of psychology 

 in the selection and training of personnel, we 

 have killed more submarines, have used 

 radar better, have better gunners, better 

 engineers, better communications both by 

 voice and by code, have been shooting down 

 more airplanes because our rangefinder oper- 

 ators were selected and trained better." 



Should another war come, victory may 

 well be, not on the side of the strongest bat- 

 talions, not even on the side of the best 

 guided missiles, but on the side which has 

 gained a vital 10 percent in the successful 

 handhng of human factor problems. 



Walter S. Hunter, Member 

 Undersea Warfare Committee 



