) be disappeared when a LORAN C receiver was used to navigate to within a few 
! hundred feet of each site, permitting visual sighting to be accomplished 
quickly. 
ts DATA PROCESSING 
The APTS data collecting mission produced two sets of data on magnetic 
tape, one containing digital data and the other the video imagery. The 
creat Salt Lake Desert Profiling Project produced 60 digital tapes and 37 
video tapes of the 16 successful flight missions. The data on the digital 
= tapes (consisting of angular readouts, accelerometer outputs, profiler 
range, tracker range, meterological data, APTS time, and housekeeping data) 
rns were processed on the Draper Laboratory central computer (IBM 3081K) to 
r produce the profile data. In this process, the inertial navigation posi- 
tions of the aircraft are fitted to the tracker-produced positions by 
if Kalman filtering to obtain best position estimates. These are then com- 
to bined with the profile range and IMU attitude data to obtain the profile 
data (table 1). Twenty-five profile points per second are produced, and 
k for each a mission number, APTS time, latitude, longitude, and elevation 
a- are given. The video image also contains the APTS time and can be matched 
to the profile data. Normally, the video image is used to determine the 
cause of outliers in the profile data. It is not clear yet how the video 
ker image will help on this project, particularly since most of the imagery is 
0- very dim because of the low sunlight conditions. An example of profile 
due data is shown in figure 7. 
ins 
Table 1.--Sample APTS profile data from the Great Salt Lake Desert 
Profiling Project 
  
  
  
Mission APTS Time Latitude Longitude Elevation 
(0.01 sec) (ft) 
lso 85070301 6641802 40?41'16.3874" 113?33*5,9361" 4218.56 
85070301 6641806 40 41 16.3839 113 33 5.8427 4218.96 
ne 85070301 6641810 40 41 16.3799 113 33 5.7504 4218.93 
- 85070301 6641814 40 41 16.3768 113 33 5.6490 4218.65 
ne 85070301 6641818 40 41 16.3750 113 33 5.5574 4218.42 
le 85070301 6641822 40 41 16.3731 113 33 5.4552 4218.53 
85070301 6641826 40 41 16.3716 113 33 5.3688 4218.56 
irm 85070301 6641834 40 41 16.3689 113 33.5.1778 4218.84 
85070301 6641839 40 41 16.3683 113 33 5.0682 4218.88 
85070301 6641842 40 41 16.3686 113 33 4.9862 4218.67 
85070301 6641847 40 41 16.3685 113 33 4.8822 4218.74 
; 85070301 6641850 40 41 16.3682 113 33 4.8014 4218.74 
85070301 6641854 40 41 16.3683 113-33 4.7179 4218.97 
r 85070301 6641858 40 41 16.3687 113 33 4.6187 4218.68 
85070301 6641863 40 41 16.3690 113 33 4.5076 4218.83 
l 85070301 6641866 40 41 16.3690 113 33 4.4223 4218.51 
85070301 6641871 40 41 16.3693 113 33 4.3236 4218.52 
85070301 6641875 40 41 16.3696 113 33 4.2318 4218.91 
85070301 6641878 40 41 16.3698 113 33 4.1498 4218.42 
85070301 6641882 40 41 16.3707 113 33 4.0488 4218.66 
85070301 6641886 40 41 16.3710 113 33 3.9574 4218.59 
' 85070301 6641890 40 41 16.3707 113 33 3.8787 4218.88 
85070301 6641894 40 41 16.3708 113 33 3.7652 4218.69 
85070301 6641898 40 41 16.3714 113.33 3.6753 4218.86 
  
285