Embraer EMB145 Operation Manual page 2214

FLIGHT
INSTRUMENTS
MAGNETIC COMPASS
The Standby Magnetic Compass indicates the airplane's magnetic
heading by sensing the earth's magnetic field. The magnetic heading
is indicated by reading a graduated horizontally-mounted card against
a fixed lubber line, which represents the airplane's longitudinal axis.
This card is graduated as follows:
Half dots between the tens dots (005°, 015°, 025°,...).
Full dots every ten degrees (010°, 020°,...).
Full dots and respective magnetic heading indication every 030°
(030°, 060°,...).
Full dots and the N, E, S and W characters at the respective
cardinal points (North, East, South and West).
Two calibration cards are supplied for the compass, one for normal
operational condition (pitots on and windshield heating off) installed
above the compass, and one for electrical emergency condition,
installed on the main panel left corner.
The Standby Magnetic Compass receives 5 V DC for internal lighting.
NOTE: Magnetic compass reading shall always be done considering
conditions written in applicable calibration cards.
Page
2-17-20
2
AIRPLANE
OPERATIONS
MANUAL
MAGNETIC COMPASS
Code
01
REVISION 37