- perform enroute navigation on a world-wide basis.
- fly nine or more three-hundred-mile flight lines while
maintaining accurate sidelap control
- compute latitude and longitude with input from navi
gation viewfinder or the electronic distance measuring
equipment to an accuracy of 0. 1 minute.
- Monitor the operation and credibility of the inertial
reference unit.
- read out the pitch and roll of the aircraft.
- read out drift angle, ground track, ground speed, true
heading, altitude track error, latitude or longitude and
range to go.
- program the airborne digital computer so that the air
craft will automatically pass over selected ground
points.
It should be pointed out that the navigation system of the
AN/USQ-28 does not attempt to position the aircraft with the same
accuracies required for horizontal control. The basic navigation
mode programs the aircraft along parallel flight paths, with accur
ate control of sidelap. The location of nadir points is accomplished
after the fact, during photo reduction.
Navigator's Viewfinder:
Figure 3 illustrates the navigator's viewfinder, that part
extending into the navigator's station. Table 1 presents the primary
specifications of the viewfinder:
TABLE 1
Search Field . . .
Field of View . .
Magnification . .
Resolution . . .
Sighting Accuracy
Tracking Rate . .
Drift
pitch+100°, -35°, roll t 50°
60°
2X, 4X
1 minute of arc
3 minutes (1 )
^2 degrees /sec.
- 20 minutes (accuracy 8 min.
1 )