il 3 i= 
Survey Flight Planning calculates survey flight parameters 
(true altitude, air base, line spacing, min./max. foreward- 
or side lap) from given data (focal length of camera, scale 
at ref. elevation, ref. elevation, max. /min. terrain elevation). 
8) 
a. calculates the angle of bank for a direct turn; input data 
Universal Survey Turn Computation Program 
are: distance between photo flight lines, true airspeed ,and 
  
  
survey drift. 
b. calculates rated turns, resp. turns with constant bank angle; 
the program decides whether a U-turn (large distance between 
photo flight lines) or S-turn (small distance between photo 
flight lines) results from the input data (distance between 
flight lines, true airspeed, survey drift). In case of U-turn, 
the number of seconds to fly straight between the two half 
turns are calculated; in case of S-turn, the number of 
"degrees-off" are computed in an iterative way in order to 
correct for the influence of wind. (Note: The slide rule 
solution has neglected the wind influence during the S-part 
of the turn) - The number of "degrees-off" is computed 
up to 90 degrees; additional displacement is obtained by 
flying à straight part between the two half-S-turns$; the 
number of seconds to fly straight is computed as well. 
(6 
  
8) This program will be described in detail in the ITC-Journal