information in connection with swinging, com-
4. Mount the
necessary optical alignment
pensating, and calibrating compasses.
equipment to the
remote compass transmitter.
Align the telescope
to a predetermined target one-
half mile or more
away.
5. Tow the aircraft into position exactly on
REVIEW SUBSET NUMBER 4
the north line by using plumb bobs or some other
accurate method.
Q1. What INS solved the problem of operating
an inertial system at the poles?
6. Compute the optical alignment correction.
Insert the correction into the optical alignment
scope. Replace the compass transmitter in the
aircraft (sighting on the same target used in step
4 above).
Q2. Having to maintain the accelerometer
referenced to a fixed point in inertial space
7. With the transmitter fastened down,
is a significant disadvantage o f the
reconnect the leads.
.
8. Using the appropriate adapter cables,
connect the compass calibrator set into the
compass system.
Q3. W h a t is the main advantage of the
The aircraft magnetic headings are set in with
geometric inertial navigation system?
the heading selector on the control console.
Record the errors as the difference between
the indicated heading and that set in with the
Q4. What two types of compensators are used
heading selector. Calibrate the compass system
components to within 0.10 of the heading
on flux valves?
selector position.
For more detailed information on compass
Q5. When must you compensate instrument
swinging, refer to Military Standards, MIL-STD-
765A. Consult this specification for additional
panel compasses for coefficient A?
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