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Source of turbine engine bleed air

Aviation Mechanic Powerplant (AMP) practice question 6 of 13 on Turbine Engines. ACS element AM.III.B.K7 · difficulty: recall. Want to answer it in a timed quiz? Use the Aviation Mechanic Powerplant (AMP) practice mode.

Question bank updated 2026-09-22

QUESTIONWhere does a gas turbine engine obtain the bleed air used for cabin pressurization and anti-icing?

  1. AFrom a tap in the turbine exhaust gas stream
  2. BFrom the accessory gearbox air pump on the engine
  3. CFrom ports at stages of the engine compressor
Show the answer and explanation

Correct answer: C. From ports at stages of the engine compressor

  • A — incorrect Bleed air is supplied by the compressor as a secondary function; the turbine exhaust is not a bleed air source.
  • B — incorrect The accessory section mounts engine and aircraft accessories, but bleed air comes from the compressor, not from a gearbox-driven air pump.
  • C — correct Bleed air is taken through small ports in the compressor case adjacent to the stage from which the air is bled, so various pressures are available by tapping the appropriate stage.

BACKGROUND

The primary function of the compressor is to supply air in sufficient quantity and pressure to the combustion burners. A secondary function is to supply bleed air for various purposes in the engine and aircraft. The exact location of the bleed ports depends on the pressure or temperature required for a particular job, and air is often bled from the final or highest pressure stage, where pressure and air temperature are at a maximum. Current applications of bleed air include cabin pressurization, heating, and cooling; deicing and anti-icing equipment; pneumatic starting of engines; and auxiliary drive units. When high-pressure bleed air would be uncomfortably or harmfully hot, such as for cabin use, it is sent through an air conditioning unit first.

STUDY TIP

Remember that bleed air is a compressor product and that stage selection sets the pressure and temperature you get. Learn the four listed uses as a short list.

KEY POINTS

  • Bleed air is a secondary function of the compressor, tapped through ports in the compressor case.
  • Tapping different stages provides different pressures and temperatures.
  • Uses include pressurization and air conditioning, anti-icing, pneumatic engine starting, and auxiliary drive units.

SOURCES

  • FAA-H-8083-32B ch01 "Compressor Section" (bleed air)
Practice the Aviation Mechanic Powerplant (AMP) test →Timed 100-question exam, by ACS area, or review your misses. Free.
MORE ON TURBINE ENGINES

SkyDrill is not affiliated with the FAA. This is an original practice item based on FAA-H-8083-32B Aviation Maintenance Technician Handbook – Powerplant, and 14 CFR part 43. Regulations and handbooks are revised; confirm details against the current edition.