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Round Dials
1
st
Ed Nov 2018
IDU-450 EFIS Software Version 8.0H (Rotorcraft)
RD-1
Round Dials
RD 1. Airspeed Display
Figure RD-1: Round Dials Airspeed Display
The airspeed display digitally displays indicated airspeed in knots, miles,
or kilometers per hour (as per aircraft “Speed Units” system limit) and is
scaled to show the entire operating range of the aircraft. Clockwise
movement indicates increasing speed. When an ADC sensor fails, the
display appears as shown in Figure RD-8.
Without airspeed
bugs
IAS bug set to 80
and indicating 80
KIAS
IAS bug set to 80
and indicating 70
KIAS
Figure RD-2: Round Dials Airspeed Display Limits
1) Gray safe-operating area from bottom of dial to
V
MIN
.
Airspeed is gray
at 0 (indicating “dead” airspeed) but otherwise green.
2) Green safe operating range area from
V
MIN
to
V
NO
.
V
MIN
refers to the
minimum speed for effective airspeed indication (usually 20KIAS,