DG Flugzeugbau DG 202, Руководство по эксплуатации самолета

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Manual Compass 46--MFK--1 BOHLI MAGNETTECHNIK AG
Edition 01.2007 Page 11 of 16
The compass may also be mounted off center, but in this case the pilot may have to slightly
move his head to the side in order to see the entire dial when circling. In cockpits with central
forward canopy locks, it pays to modify the knobs of levers, by--passing the compass. Use
antimagnetic materials (aluminium, brass, etc.). The compass base plate is bolted against a
surface which should be as vertical as possible in flight.
The drilling plan gives details on the three mounting holes and the holes for the shaft and cen-
tral screw. The upper edge of the top hole for the shaft shall, if possible, be located just slightly
below the instrument cover board. Examples of suggested installation possibilities are shown
on enclosed sketches. The shaft with the bank adjusting knob may be brought through the
instrument panel at the most suitable location. Drill a ø 5.2 mm hole, or a slot of 5.2 mm width
near the edge of the instrument cover board (thus the entire assembly may be taken off with
the cover board). Should another deep instrument already occupy the top central space on
the panel, the it may be necessary to install an additional (optional) universal joint and an addi-
tional support in order to by--pass said instrument with the bank adjusting shaft.
Fig. 11
Drilling plan 1:1
Instrument cover board
Levelling of compass
For levelling the compass it is important to know the fuselage pitch angle which corresponds
to a flying speed of 100 to 110 km/h (62 to 70 mph). For gliders without flaps this will give the
lowest average indication errors (over the entire speed range) on headings East and West.
In the case of gliders with flaps these errors are negligible since the pitch angle of the fuselage
remains constant over a wide speed range. If the pitch angle of the fuselage at the above indi-
cated speed is not known, it may be determined during a flight with the adjustable water--level
supplied with the compass. This must be fixed somewhere in the cockpit (canopy frame, etc.)
for this purpose. If desired, the water--level may remain mounted in the plane and can later
serve to verify the pitch angle of the fuselage at which the compass always indicates correctly.