674 



DISPLAY SYSTEM DESIGN PROBLEMS 



Red 



Green 



Red 



Green 



Fig. 12-49 Terrain Avoidance Displays. 



flight plan can be developed from the display, but information of the height 

 of the obstacles is not readily presented. 



Mechanization of indicators has been accomplished using both mono- 

 chromatic and two-color tubes. In a monochromatic display only the object 

 of danger is displayed. Those objects are shown which, because of their 

 range and altitude position, are an immediate barrier to aircraft. Using 

 multicolor displays, differentiation of objects in near or far range and above 

 and below the line of flight is graphically displayed. In the color display, 

 quantizing of the radar information is mechanized to show the objects 

 which constitute a danger in red color. Objects which are not barriers to the 

 aircraft flight are displayed in green. 



Improvement of these displays to show more subtle changes in terrain 

 will come from use of the advanced tubes which offer greater color differen- 

 tials. 



Windshield Projection. Much work is being done to relieve the 

 cockpit and instrument display complex that is apparent in modern aircraft. 

 Simplification of instrumentation and windshield projection of the radar 

 information are approaches to the problem. 



Windshield projection, in its simple form, presents the typical displays 

 which have been discussed onto a surface where the pilot is naturally 

 looking. Much more sophisticated windshield displays are being developed, 

 in which information of a tactical nature as well as radar data are presented 

 in a more easily understandable form. Windshield display is developed by 

 use of either transparent tubes like the Aiken tube or mirrors. Fig. 12-50 

 illustrates a configuration of the use of a diachroic mirror to effect a 

 windshield display. With the usable brightness level of the storage tube, 

 the attenuation of this system is not of great consequence. 



Contact Analogue. The symbolic display of the AI radar is a coded 

 language which the operator must learn. Although it is not complex, it has 

 no analogy in human experience. Experimental efforts are being made by 



