Of significance was the multi-altitude test per 
formed across the Ajo-Catalina line* Data was acquired 
on two different days approximately three weeks apart. 
Twenty-eight (28) separate lines were flown at altitudes 
varying from 36,34-9 feet to below the line of sight 
(4,745*)• The internal consistency of this data was 
0.0006 nautical mile probable error or 3.6 feet. Refer 
to Table 5 on page 20 for detailed results. 
The controlled photography test was performed on two 
separate days over the 36 mile by 30 mile area located in 
the vicinity of Phoenix, Arizona. Each mission consisted 
of seven north and south flight lines and three east and 
west flight lines. Over one hundred (100) photographs 
were obtained for each mission. Analysis of this test 
indicates a capability of determining nadir points to a 
circular probable error of 3.37 meters. The precision of 
Shiran was further depicted during the controlled photo 
graphy tests by the use of the redundant data obtained 
from the four station ranging capability. Mean northing 
and easting coordinates were computed for each nadir point 
from the four station combinations. The deviations of the 
individual northings and eastings were determined from the 
mean values and plotted. Figure 7 depicts the plotting of 
these points for the first photo mapping mission. The 
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