Horizontal Situation Indicator - Cirrus SR22 Pilot Operating Handbook

C D
IRRUS ESIGN
SR22
Serials w/ MD302 Standby Attitude Module:
The MD302 Standby Attitude Module is mounted on the LH bolster panel
and displays the current barometric corrected altitude. The instrument
senses the local barometric pressure adjusted for altimeter setting and
displays the result in the Altitude Window. The altitude units are
user-configurable in feet or meters. The Altitude Window/Pointer sweeps
the altitude tape and denotes the current BARO-corrected altitude. The
BARO Window shows the currently selected barometric altitude. The
BARO units are user-configurable in IN.HG or MBAR. The barometric
setting on the MD302 will automatically synchronize to the setting on the
Garmin avionics, and can be manually adjusted by turning the Control
Knob while in Flight Mode.
28 VDC for the MD302 Standby Attitude Module is supplied through the
5-amp STDBY ATTD A circuit breaker on ESS BUS 1 and the 5-amp
STDBY ATTD B circuit breaker on MAIN BUS 1.
All Serials:
The standby altimeter does not have automatic position error corrections;
calibration corrections are necessary. Because the PFD has automatic
corrections and the standby does not, differences between the two indica-
tions are typical (difference is the greatest at high altitudes and high
airspeeds, where the position error corrections are the highest).

Horizontal Situation Indicator

The horizontal situation indicator is displayed along the lower center of the
PFD. Heading data is provided by the Attitude and Heading Reference
System (AHRS) and the onboard magnetometers. The HSI displays a
rotating compass card in a heading-up orientation. Letters indicate the
cardinal points and numeric labels occur every 30°. Major tick marks are at
10° intervals and minor tick marks at 5° intervals. Reference index marks
are provided at 45° intervals around the compass card. A circular segment
scale directly above the rotating compass card shows half and standard
rates of turn based on the length of the turn rate trend vector.
The HSI presents heading, turn rate, course deviation, bearing, and naviga-
tion source information in a 360° compass-rose format. The HSI contains
a Course Deviation Indicator (CDI) with a course pointer arrow, a
To/From arrow, a sliding deviation bar, and scale. The course pointer is a
single line arrow (GPS, VOR1, and LOC1) or a double line arrow (VOR2
and LOC2) which points in the direction of the set course. The To/From
arrow rotates with the course pointer and is displayed when the active
NAVAID is received.
The HSI heading reference bug is set using the HDG select knob on the
GMC 707 AFCS. The selected heading is displayed in a window above the
upper LH 45° index mark and will disappear approximately 3 seconds after
the HDG select knob stops turning.
P/N 13772-006
Reissue A
S 7: A
ECTION IRPLANE AND
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