Learjet 60 - Standby Airspeed;Mach Indicator; Standby Altimeter

Pilot's Manual
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Learjet 60
I STANDBY AIRSPEED/MACH INDICATOR (Aircraft 60-001 thru 60-248)
The standby airspeed/Mach indicator is installed on the center instru-
ment panel . The indicator face consists of a stationary, circular airspeed
scale
reading
from 0 to
400
knots, a moveable Mach scale, an airspeed/
Mach pointer and a maximum allowable marker (barber pole) . The
Mach scale rotates with
changes in altitude to maintain the
correct
Mach/airspeed relationship for any given altitude . The maximum al-
lowable marker rotates with the Mach scale and maintains a position at
0 .75 Mi . The pointer responds to pilot and
static
pressure
from
he
standby pitot-static
probe . The standby airspeed/Mach indicator
is
used to cross check pilot and copilot airspeed displays and serves as a
back up unit in the event both pilot's airspeed data becomes invalid,
I STANDBY ALTIMETER (Aircrciff60-001 thru 60-248)
One of two types of standby altimeter is installed on the center instru-
ment
panel . The altimeter displays altitude on the counter-drum-
pointer presentation . The altimeter dial is graduated in 2-foot incre-
ments from 0 to 1000 . The pointer makes one complete revolution per
1000 feet of altitude . The counter rotates to produce a digital display of
altitude in ten thousands and thousands of feet . The hundreds, tens
and units places are fixed zeros . A Kollsman window displays the
altimeter setting in inches of mercury (IN HG) . The altimeter setting is
entered by rotating the set knob on the altimeter bezel . The standby al-
timeter responds to static pressure from the standby pitot-static probe .
The standby altimeter is
used to cross check pilot and copilot altitude
displays and serves as a back up unit in the event both pilot's altitude
data becomes invalid .
STANDBY AIRSPEED/MACH INDICATOR AND ALTIMETER (Typical)
Figure 5-8
516
P11423
Change 4