pilot's CRT Graphic Guidance Display 
2.1 
  
CRT 
  
  
  
(5" Screen) 
  
Pilot's Control 
(Hand-held Terminal) 
  
  
  
  
  
  
  
  
  
CPNS 
Navigation : : : FIG. 2: Components of CPNS - the Computer-controlled 
Sensor Photo Navigation System Fie 
X/Y 
e—{ True Airspeed | Positioning, airspeed, heading and camera pitch/roll 
.—| Magnetic Heading] data are processed by a digital computer to present 
| Computer {Plotter 1] guidance information on a graphical screen and to 
«— {Magnetic Tape | produce camera exposure commands for pin-pointed 
«—f[az, Statoskop_ | aerial photography. It is possible to release camera 
  
  
  
  
    
  
    
  
shutter only if flight parameters are within 
Exposure command 
Data Annotation specifications, SPEC push button pressed on the 
hand-held terminal. This terminal allows the pilot 
easy communication with the computer. 
   
AERIAL 
CAMERA 
  
  
Pitch/Roll, Gyro 
The basic functions of CPNS 
The basic functions of CPNS are threefold: 
     
2.1.1 Computer supported mission planning and photo administration 
The coordinates of all exposure stations are computed and stored in the computer's memory. Input 
values are: 
either: coordinates of reference point(s) 
+ direction(s) of reference line(s) 
+ length of reference line(s) 
+ number of photos per reference line 
+ number of parallel lines plus spacing 
line numbers, altitudes 
or: coordinates of starting point(s) and end point(s) of reference line(s) 
* number of photos per reference line 
* number of parallel lines plus spacing 
line numbers, altitudes 
or: line number(s), altitude(s), line direction(s) 
* coordinates of exposure stations 
A control plot with planned survey lines and preprogrammed exposure stations may be requested.;or 
another plot with planned survey lines plus exposure stations where photos have been taken already 
(interactive correction is possible to delete non-acceptable photos). The latter plot is most 
useful for in-flight decisions under unfavourable meteorological conditions. It easily visualizes 
where to fire the camera to fill the gaps. 
2.1.2 Efficient aircraft guidance based on standardized survey flight procedures 
Guidance information is presented to the pilot in graphical form on a screen. The principle 
"follow the needle" (aircraft fixed, ground moving) - well known to pilots - is observed. Three 
display modes are available: 
- APPR - approach mode 
This mode guides the airplane to the mission area. 
- TURN - turn mode 
This is to intercept a selected survey line. All turns are standardized 180? - turns 
(constant bank angle or constant rate of turn). Turns will therefore be U-turns, S-turns 
or X-turns. 
- LINE - line mode 
Line mode is displayed after pushing the LINE mode push button and introducing the line 
number or automatically after TURN mode as soon as the airplane is within the scale limit 
of the screen but not before one minute has passed after TURN mode. A gap reminder visua- 
lizes whether the airplane is still on-line or not. Actual pitch and roll angles 0/76€ comers re 
displayed as long as these values are within specification. 
With respect to exposure commands two possibilities exist: 
a) To delete shutter release whenever pitch/rol1/lateral piloting erroris out of specs {SPEC pressed) 
At the end of line exposure station numbers are displayed where excessive pitch/roll/ 
lateral piloting error have been existing, - actual values are displayed. Acceptance or 
rejection of total line or individual photos may be carried out. 
For all three modes three display scales may be selected at the control panel. 
  
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