aural tone sounds, and the preselect dig-
ital display and box change to amber.
When the aircraft is within 250 feet of the
selected altitude the digits change to ma-
genta and the box to cyan. Once the alti-
tude has been captured, deviations greater
than 250 feet will alert the pilot by sound-
ing an aural tone and the altitude prese-
lect display changes to amber (Figure
16-34).
Barometric Correction Readout
This display is directly beneath the baromet-
ric altitude tape display and can be set to ei-
ther inches of mercury or HectoPascals.
Airspeed
The airspeed display is presented as a verti-
cal tape to the left of the ADI. The airspeed
indicator provides a scrolling tape and a rolling
digital readout for accurate interpretation of
airspeed. The airspeed information provided
consists of the following:
• IAS/Mach – Indicated airspeed is the
same as calibrated airspeed received from
the ADC for this airplane. The display
shows indicated airspeed or Mach as a
vertical tape and rolling drum, as selected
on the Flight Guidance Controller (FGC).
The SPD knob on the FGC panel has an
integral pushbutton which is used to tog-
gle between the display of the IAS tape
and the Mach tape on the PFD. The Mach
tape cannot be selected on the ground or
inflight below .40M
I
.
The airspeed display will automatically
switch to the appropriate mode (IAS or
Mach) when using the FLC mode of the
FD and the climb or descent schedule
switches from IAS to Mach or vice-versa
(Figure 16-48). Also, the airspeed scale
will automatically switch from Mach to
IAS if the Mach tape is displayed and the
airspeed decreases to below .40M
I
.
When IAS is selected on the vertical
tape, the equivalent Mach number will be
digitally displayed at the bottom of the
tape if Mach is at or above .40M
I
(Figure
16-34) and when the Mach tape is dis-
played, the equivalent IAS will be digi-
tally displayed at the bottom of the tape
(Figure 16-33).
The IAS tape (Figure 16-34) is annotated
in 20 knot increments, beginning at 40
knots, with tick marks in 10 knot incre-
ments. The Mach tape(Figure 16-33) is in-
dexed from 0 to 1.10 Mach, with digits
at 0.04 Mach increments, and tick marks
in 0.02 Mach increments. The rolling
drum digital display is in 1 knot or .01
Mach increments.
• Airspeed trend vector – As illustrated
in Figure 16-34, the airspeed trend vec-
tor represents the airspeed the aircraft
should attain in 10 seconds if the current
acceleration schedule is maintained. The
trend vector is the same symbology for
IAS or Mach, and is inhibited on the
ground.
• Selected airspeed – Selected airspeed is
displayed digitally at the top of the air-
speed tape, and as a notched rectangular
magenta bug that travels along the air-
speed tape vertically. This reference is set
using the SPD button and SPD set knob
on the guidance controller.
• Overspeed indicator – The overspeed in-
dicator is overlaid on the airspeed tape as
a red bar thermometer that extends from
the top of the airspeed/Mach tape to the
overspeed value. If an IAS tape is dis-
p l a y e d , t h e i n d i c a t o r r e p r e s e n t s
Vmo/Mmo (Mach trim On or Off) or flap
overspeed, whichever is less. If a Mach
tape is displayed, the indicator will dis-
play the Mmo value provided by the ADC.
The bar tape will grow or shrink as the
configuration and airspeed of the air-
plane changes. The digital airspeed value
changes to amber when the airspeed trend
vector reaches the Vmo cue and changes
to red when the airspeed exceeds Vmo.
Overspeed limits for the flaps are as il-
lustrated in Table 16-3.
L E A R J E T 4 5
P I L O T T R A I N I N G M A N U A L
16-54
FOR TRAINING PURPOSES ONLY
FlightSafety
international