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Discharging CO2 during a turbine ground fire

Aviation Mechanic Powerplant (AMP) practice question 4 of 9 on Engine Inspection. ACS element AM.III.C.R2 · difficulty: standard. Want to answer it in a timed quiz? Use the Aviation Mechanic Powerplant (AMP) practice mode.

Question bank updated 2026-09-22

QUESTIONA fire persists during the ground starting cycle of a turbine engine after the fuel shutoff lever is moved to off. Where should carbon dioxide be discharged?

  1. AInto the engine inlet duct while cranking.
  2. BInto the engine exhaust while cranking.
  3. CDirectly into the exhaust after cranking stops.
Show the answer and explanation

Correct answer: A. Into the engine inlet duct while cranking.

  • A — correct If the fire persists, carbon dioxide can be discharged into the inlet duct while the engine is being cranked.
  • B — incorrect Carbon dioxide must not be discharged directly into the engine exhaust, because doing so may damage the engine.
  • C — incorrect Cranking is continued to expel the fire, and the exhaust is still the wrong place to aim the agent because of the damage it can cause.

BACKGROUND

If a fire occurs or the fire warning light illuminates during the starting cycle of a turbine engine, the fuel shutoff lever is moved to the off position and the engine is kept cranking or motoring until the fire has been expelled from the engine. If the fire persists, carbon dioxide (CO2) can be discharged into the inlet duct while the engine is being cranked. CO2 must not be discharged directly into the engine exhaust, because it may damage the engine. If the fire is on the ground under the engine overboard drain, or at the tailpipe with fuel dripping to the ground and burning, the CO2 is discharged on the ground rather than on the engine. If the fire cannot be extinguished, all switches are secured and the aircraft is left.

STUDY TIP

Fix the order in mind: fuel off, keep cranking, CO2 into the inlet, agent on the ground for a fuel pool fire, and never into the exhaust.

KEY POINTS

  • Move the fuel shutoff lever off and keep cranking to expel the fire
  • Discharge CO2 into the inlet duct while cranking if the fire persists
  • Never discharge CO2 directly into the exhaust; it may damage the engine

SOURCES

  • amp-powerplant/ch10.txt "Ground Operation Engine Fire"
Practice the Aviation Mechanic Powerplant (AMP) test →Timed 100-question exam, by ACS area, or review your misses. Free.
MORE ON ENGINE INSPECTION

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.