5. Demagnetization Procedure
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A. Apply electrical power (Ref 24-22-00).
B. Extend the leading edge outboard flaps (Ref 27-81-00).
C. Energize the demagnetizer at least 5 feet away from the airplane.
D. Slowly move the demagnetizer in toward the outer flap linkages, taking care not to come within 3 feet of the flux valve.
E. Allow the flat surface of the demagnetizer to contact the flap linkages. At a rate not to exceed one inch per second, slowly move the demagnetizer from end to end, in both directions, over as much of the accessible surface area of the flap linkages as possible.
F. Slowly withdraw the demagnetizer, taking care not to come within 3 feet of the flux valve. Switch off the demagnetizer at least 5 feet away from any part of the airplane.
G. Hold the field strength meter against the flap linkages just demagnetized. Pass the meter along the entire length of the flap linkages. If the meter reading exceeds 10 gauss at any point, repeat steps C. thru G., as necessary, on the same flap linkages.
H. Repeat steps C. thru G. on the opposite side of the airplane.
EFFECTIVITY
ALL 01 Page 201 Oct 25/8034-21-11
I. Retract and extend the leading edge outboard flaps. At the same time check the magnetic compass for zero deviation. If any deviation is noted repeat steps C. thru H.
6. Restore Airplane to Normal
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A. Retract the leading edge outboard flaps, and remove electrical power.
EFFECTIVITY
ALL 01 Page 202 Oct 25/8034-21-11
STANDBY MAGNETIC COMPASS - DESCRIPTION AND OPERATION
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1. General (Fig. 1)
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A. The standby compass is a highly sensitive instrument of liquid filled design employed by the pilot as a quick directional reference, and as an auxiliary compass. The card assembly which indicates magnetic direction is illuminated by means of a bulb located at the top of the compass. The bulb is controlled by a toggle switch located above the compass. The bulb cover is designed to allow passage of light through the glare filter and at the same time reflect and diffuse the residual light. The cover also acts as a bulb holder and enables the bulb to be removed from the compass face. This permits easy replacement of the bulb without removing the compass from the panel. The light is powered by 28 volts dc from the battery bus.
EFFECTIVITY
ALL 01 Page 1 Oct 10/7334-22-00
Standby Magnetic Compass Location
Figure 1
EFFECTIVITY ALL
701 Page 2
34-22-00
Oct 10/73
STANDBY COMPASS - MAINTENANCE PRACTICES (COMPASS SWING)
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1. General
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A. This procedure contains one task. The procedure uses a standby compass calibrator instead of the usual tow-around procedure to do a swing of the standby compass.
NOTE: Air bubbles can occur in the standby magnetic compass because of
____ temperature change and/or decrease of liquid. Maintenance limits made for liquid quantity make sure of satisfactory compass operation. When air bubble is larger than 3/8-inch wide and 1/8-inch high, with the glass approximately vertical position, replace the standby compass.
B. The task has two parts. The first part is to do a swing of the standby compass through four compass points (N, E, S, W). Use this procedure for compass calibration. The second part is to do a swing of the standby compass through 12 compass points that are approximately 30 degrees apart. Use this procedure to measure the remaining errors and to make sure the standby compass heading is accurate. Use this data to make the compass correction card. This card must stay with the standby compass.
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