ATA 49 APU

What is the primary function of the Auxiliary Power Unit (APU)?. Electrical power generation. Engine thrust. Fuel storage. Wing anti-ice.

Besides electrical power, what else does the APU provide?. Engine cooling. Air conditioning in-flight. Navigation assistance. Oxygen supply.

When does the air intake flap open and close?. Opens when APU is ON, closes when OFF. Opens during landing, closes during takeoff. Opens during takeoff, closes during landing. Opens when the main engines are running.

What is the purpose of the air intake flap?. Engine cooling. Reducing noise. Pneumatic supply. Preventing fires.

Where is the APU installed on the aircraft. In the cockpi. In the wing. In the fuselage tail cone. In the landing gear.

How is vibration transmission reduced between the APU and the aircraft structure. Through tie rods. Through isolators. Through exhaust muffler. Through air intake.

How is the APU attached to the structure brackets in the APU compartment ceiling?. Through tie rods. Through bolts. Through welding. Through adhesive.

What is the purpose of the vibration isolators in the APU mounting system?. To increase vibration. To reduce noise, prevent transmission of vibrations. To transfer vibrations to the aircraft structure. To connect to the APU three point mounting system.

What is the primary purpose of the drain system in the APU compartment?. To collect fluids for reuse. To prevent fluid accumulation. To supply water for aircraft cleaning. To collect APU exhaust gases.

How are fluids collected and removed from the APU compartment?. Through a drain mast. Through an APU exhaust pipe. Through an APU cooling system. Through an APU fuel line.

The Auxiliary Power Unit (APU) is a constant-speed ________ engine. electric. JET. gas turbine. propeller.

The APU provides electrical power for the aircraft systems, bleed air for various functions, and bleed air cutoff above the specified ________ limit. altitud. temperature. manufacture. spee.

The air intake flap opens when the APU MASTER SWITCH is set to ON and closes when the MASTER SWITCH is set to OFF and the APU ________. When open, it supplies air to the APU inlet for combustion and pneumatic supply. starts. stalls. accelerates. stops.

In case of failure, the air intake flap can be opened or closed manually by a manual ________ device. override. control. lever. switch.

The APU is installed in a fireproof compartment located in the fuselage ________ cone. wing. tail. nose. cockpit.

Vibration isolators are installed between the APU mount brackets and the tie rods to reduce the transmission of A/C vibrations and shocks to the APU. The isolators also prevent the transmission of vibrations from the APU to the A/C ________. wings. engines. structure. cockpit.

The air intake system ducts ambient air to the APU plenum chamber. An air intake flap cuts off the air supply when the APU does not operate. In case of failure, the air intake flap can be opened or closed manually by a manual ________ device. override. control. lever. switc.

The air intake duct, which is composed of a diffuser and elbow, provides correct airflow to the APU plenum. The air intake duct is attached to the ________ access door. left. right. top. rear.

The exhaust system lets the APU exhaust gas flow into the atmosphere and muffles the ________ from the exhaust. The exhaust muffler thermal insulation protects the A/C structure. smoke. noise. hea. vibration.

The exhaust muffler thermal insulation protects the A/C ________. wings. engines. structure. cockpit.

Two access doors allow access to the APU compartment. The access doors on the bottom of the tail cone open ________ to allow the APU to be inspected, lifted, and lowered. inward. outward. upward. downward.

Two access doors allow access to the APU compartment. The access doors on the bottom of the tail cone open outward to allow the APU to be inspected, lifted, and ________. secured. fixed. raised. lowered.

A drain system prevents the collection of fluids in the APU compartment. Any fluid that may accumulate in the APU compartment is delivered to a ________ mast. Some of the fluids are collected in a drain tank in the APU compartment, which is emptied through the drain mast when the A/C is above 200 kt. fuel. drain. water. hydraulic.