Handbook of Civil Engineering Calculations

(a) Elevation normal to line of flight (c) Elevation parallel

to line of flight

FIGURE 32

XA = (XJp)B and YA = (yalp)B. Then XR = (+86.46/92.03)5 = +0.93955; YR =
(-54.32/92.03)5 = -0.59025; X 8 = (+29.41/91.85)5 = +0.32025; Y 8 = (+56.93/91.85)5 =
+0.61985.

2. Express the distance between the control points in terms of the
   air base; solve the resulting equation
   Disregarding the difference in elevation of the two points, we have (RS)
   2
   = (XR-XS)
   2
   
   
   • (YR- Y 8 )
     2
     . Now,XR-XS = +0.61935 and YR- Y 8 = -1.21005. Then 2073
     2
     = [(0.6193)
     2
     
     
     • (1.2100)^2 ]5^2 ,or5=1525m.
     
     
     
     
   
   
   
   

Datum plane

Plane of

photograph

B = Air base

(b) Plan

Photograph I Photograph 2

Direction of

flight