Turbine powers APUs
Turbine powers APUs
Study online at https://quizlet.com/_j5qc4b
1. Name the main components of a typ- A small power turbine (for power and bleed air) and
ical APU: an electrical generator.
2. When is the greatest demand placed When supplying bleed air.
on an APU?
3. How is an APU generally started? With its own electrical starter and battery power.
4. Where does the APU get its fuel sup- Aircraft's main fuel tanks.
ply?
5. At what speed does a gas turbine At or near its rated speed. The APU fuel control auto-
APU operate and how is this speed matically adjusts the fuel flow to maintain the rated
maintained? speed.
6. What is used to prevent a heavily A load control valve, modulates the pneumatic load to
loaded APU from exceeding its max- maintain EGT's within limits.
imum EGT?
7. How is an APU shut down and why is APU bleed air valve closes and APU runs in Idle be-
this procedure used? tween 3 to 5 minutes to reduce and stabilize EGT. This
prevent damage due thermal shock.
8. What powers the variable inlet guide Fuel pressure.
vanes (IGV) used on some APU's to
regulate compressor intake airflow?
9. What is the function of an APU on To supply ground electrical and pneumatic power
modern transport category aircraft? to aircraft systems when the engines are not run-
ning, and as backup source of electrical power during
flight.
10. Name at least two uses for APU pro- Engine Starting, Ground air conditioning and Anti-ic-
duced pneumatic power. ing.
1/2
Turbine powers APUs
Study online at https://quizlet.com/_j5qc4b
1. Name the main components of a typ- A small power turbine (for power and bleed air) and
ical APU: an electrical generator.
2. When is the greatest demand placed When supplying bleed air.
on an APU?
3. How is an APU generally started? With its own electrical starter and battery power.
4. Where does the APU get its fuel sup- Aircraft's main fuel tanks.
ply?
5. At what speed does a gas turbine At or near its rated speed. The APU fuel control auto-
APU operate and how is this speed matically adjusts the fuel flow to maintain the rated
maintained? speed.
6. What is used to prevent a heavily A load control valve, modulates the pneumatic load to
loaded APU from exceeding its max- maintain EGT's within limits.
imum EGT?
7. How is an APU shut down and why is APU bleed air valve closes and APU runs in Idle be-
this procedure used? tween 3 to 5 minutes to reduce and stabilize EGT. This
prevent damage due thermal shock.
8. What powers the variable inlet guide Fuel pressure.
vanes (IGV) used on some APU's to
regulate compressor intake airflow?
9. What is the function of an APU on To supply ground electrical and pneumatic power
modern transport category aircraft? to aircraft systems when the engines are not run-
ning, and as backup source of electrical power during
flight.
10. Name at least two uses for APU pro- Engine Starting, Ground air conditioning and Anti-ic-
duced pneumatic power. ing.
1/2
