6.12.1 SWING PROCEDURE - MAGNETIC C

6.12.1 SWING PROCEDURE - MAGNETIC COMPASS. The swing procedure for the magnetic compass
is divided into three stages (paragraphs 6. 12. 2 through 6.12.4) and must be accomplished in
the order given.
6.12. 2 PRE PARA TION AND GENERAL INSTRUCTIONS - COMPASS SWING PROCEDURE.
a. Set aircraft on a coznpass base when possible.
Note
When a compass base is not available, a magnetic
sighting compass may be used iDstead. Add or
subtract 180 degrees when using the sighting compas
s facing aft. When facing forward, the compas s
reads directly.
I b. Start and run engines (refer to Flight Manual). Increase to cruising rpm for each reading.
Co Switch ~n electrical and radio systems (refer to Parts 7 and 8).
d. Set compensator to neutral position using non-znagnetic tool provided behind the correction
card holder.
6.12.3 REMOVAL OF COMPASS INDEX ERROR. To reznove compass index error, proceed as
follows:

ficient
time for compass to settle before taking each reading.
b. Calculate deviation between aircraft compass reading and actual magnetic heading.
c. Add deviations algebraically and divide sum by four. The result is the index error.
d. Loosen mounting screws and rotate compass in appropriate direction, noting amount of rotation.
Use a non-magnetic screwdriver.
Note
If error is plus (+), rotate compas s counter clockwise.
1£ error is minus (-), rotate in a clockwise
direction. Amount of rotation must equal index
error.
e. Secure :mounting screws.