GH-3100
Installation & Operation Manual
Page 5-18
Operation
TP-559
March 30, 2017
Revision K
5.2.4.1.8 Mach Digital Readout Format
The mach digital readout is shown in the mach box positioned at the top of the IAS tape, at the left side of
the display. The box is black with no border.
The mach digital readout is two medium size digits preceded by a decimal point (“
.
”) and followed by a
medium size “M” descriptor as shown in Figure 5-9B or C. The mach digital readout character color
matches the configured IAS Digital Readout Character Color.
The mach digital readout will display a minimum mach of 0.45 through a maximum mach of 0.99 with
resolution of 0.01 mach. If the aircraft exceeds the maximum mach readout will continue to display 0.99
until the aircraft airspeed decreases below the 0.99 mach display maximum.
The mach digital readout turns ON and OFF. When the Mach Digital Readout is OFF, the IAS tape
continues to the top of the display area (refer to Figure 5-9A). When the mach digital readout is ON, the
mach digital readout is drawn “on top” of the IAS tape and attitude display area (refer to Figure 5-9B or
C). The “on top” state is defined so as the IAS tape and attitude display do not interfere with the mach
digital readout.
When IAS PART 27/29 is configured for OFF and the mach digital readout is OFF and the mach data is
greater than or equal to 0.45 mach, the mach digital readout shall be turned ON.
When IAS PART 27/29 is configured for OFF and the mach digital readout is ON and the mach data is
less then or equal to 0.40 mach, the mach digital readout shall be turned OFF.
5.2.4.1.9 IAS Display Invalidity
An invalid IAS display omits the IAS tape tic marks, IAS tape scale digits, IAS digital readout digits,
mach digital readout digits, and the V
MO
or V
NE
bars. It includes the mach box except when configured for
PART 27/29.
When AIR DATA INVALIDITY TYPE is configured for X and an invalid IAS display is shown an “X”
is drawn over the tape area as well as the IAS digital readout area (refer to Figure 5-10B).
When AIR DATA INVALIDITY TYPE is configured for BOX W/DESCRIPTOR (with an invalid IAS
display) an “IAS” in large size characters is shown with a border and drawn in the tape area above the
IAS digital readout area (refer to Figure 5-10A).
NOTE
Heading information failure displays IAS invalidity.
A.
B.
Figure 5-10: IAS Invalidity Displays