Super 80 Professional – AOM
APU
Section 9 Page 3
Super 80 Professional – Aircraft Operating Manual
Coolsky, 2018
CONTROLS AND INDICATORS
1. APU EGT GAUGE
Indicates percent of maximum continuous
APU exhaust gas temperature.
2. APU PERCENT RPM GAUGE
Indicates APU RPM as a percentage of an
established normal operating RPM. Normal
operating range is indicated by a green arc
between 95 and 105 percent RPM.
3. APU FIRE AGENT SWITCH
For description see Fire Protection – Section
12.
4. APU AIR SWITCH (Ground operation)
ON
APU bleed control valve opens to
provide APU bleed air to the airplane
pneumatic system.
AIR COND COLDER Closes turbine bypass
valve and increases differential
pressure across air conditioning
turbine lowering temperature of
conditioned air during ground
operation. Use of this switch position,
although providing cooler air,
significantly reduces cockpit / cabin
airflow.
OFF
Remove electrical power from door
control circuit.
5. APU FIRE CONT SWITCH
For description see Fire Protection – Section
12.
6. APU MASTER SWITCH
START (Momentary) Initiates APU start.
Release to RUN after observing initial
rise in RPM.
RUN Normal APU operating mode.
OFF
Automatically shuts off bleed air
regardless of AIR switch position and
shuts down APU. Note: The APU is
also shut down if the battery switch is
set to OFF.
7. APU DOORS CONTROL SWITCH
AUTO Automatically selects ram door
position for starting and non ram
door position for ground and flight
operation.
RAM (Momentary) Provides manual
override to open ram door.
Note: The click area to open/close the
guard, is located just right of the switch.
