AGK Engines - APU Flashcards
What is an APU
GAs Turbine unit which offer an excellent power to weight ratio
How is the APU started?
Small electric starter motor powered from the a/c main batteries
Usually in the rear fuselage so that its exhaust is clear of passengers, crew and ground staff
APU inlet inlets are of two general types…
A permanently open APU inlet in the form of an NACA duct
An inlet door which opens with APU activation
What does the APU do?
Generates pressurised air and electrical power to allow a/c to operate without ground support
Provide back up electrical power
Provide high pressure air to start an engine
Provides air for cabin pressurisation and conditioning on the ground
APU Auto Shut Down
Fire Warning
Excessive EGT
Low Oil Pressure
High Oil Pressure
Airspeed/Altitude Limits Exceeded
APU Overspeed
High Bleed Air Temperature
APU Schematic
Typical Airborne APU Capability
