AMS 271, Recip. Engines - Unit 6 Exam Study Set
Critical Altitude - ANSWER Max altitude at which an engine can maintain a specified
power output (max rated power)
Naturally Aspirated - ANSWER Air induction with the use of ram air
Naturally aspirated components - ANSWER - Air Scoop
- Filter
- Air Box
- Metering Device
- Induction Manifold
- Induction Pipes
Where is the air filter installed? - ANSWER Near the air scoop
Types of air filters - ANSWER - Wetted Mesh (Filaments)
- Wire Mesh (Flock)
- Pleated Paper (replaceable)
- Polyurethane
True or false: Air induction filters are designed to filter out water. - ANSWER False; Can
,filter out dirt, dust, sand, and other foreign particles
Characteristics of polyurethane filters - ANSWER - Most effective
- Replaceable
- Coated with glycol
What 2 filters are serviceable/reusable? - ANSWER Wetted mesh and wire mesh
What are wetted and wire mesh filters immersed in? - ANSWER Engine oil
Most common air filter used on modern aircraft? - ANSWER Polyurethane
How often should you replace air filters? - ANSWER Every 200 hrs, 12 months, overhaul,
or when 50% covered in foreign material
Air Box - ANSWER Routes induction air from filter to fuel metering device
Induction Manifold - ANSWER Connects all induction pipes to respective cylinders
3 purposes of the induction manifold - ANSWER - Warm fuel/air for atomization
- Cools engine oil
- Reduces induction icing
, Carburetor Air Temperature (CAT) - ANSWER Measures carbs temp for possible icing or
detonation
Where is the CAT located? - ANSWER Carb air inlet
What is the probable cause of an induction system leak after the carb? - ANSWER Lean
Mixture
What is the probable cause of an induction leak before the carb? - ANSWER Unfiltered
air
What is the probable casue of induction system icing on a fixed pitch prop aircraft? -
ANSWER Engine RPM decrease
What is the probable cause of induction system icing on a constant speed prop aircraft?
- ANSWER Decrease in MAP
Forced Induction - ANSWER Air induction by the use of mechanical force to increase
MAP at high altitudes
Turbine and compressor - ANSWER Exhaust flow drives turbine which drives compressor
to create forced induction of clean filtered air.
Critical Altitude - ANSWER Max altitude at which an engine can maintain a specified
power output (max rated power)
Naturally Aspirated - ANSWER Air induction with the use of ram air
Naturally aspirated components - ANSWER - Air Scoop
- Filter
- Air Box
- Metering Device
- Induction Manifold
- Induction Pipes
Where is the air filter installed? - ANSWER Near the air scoop
Types of air filters - ANSWER - Wetted Mesh (Filaments)
- Wire Mesh (Flock)
- Pleated Paper (replaceable)
- Polyurethane
True or false: Air induction filters are designed to filter out water. - ANSWER False; Can
,filter out dirt, dust, sand, and other foreign particles
Characteristics of polyurethane filters - ANSWER - Most effective
- Replaceable
- Coated with glycol
What 2 filters are serviceable/reusable? - ANSWER Wetted mesh and wire mesh
What are wetted and wire mesh filters immersed in? - ANSWER Engine oil
Most common air filter used on modern aircraft? - ANSWER Polyurethane
How often should you replace air filters? - ANSWER Every 200 hrs, 12 months, overhaul,
or when 50% covered in foreign material
Air Box - ANSWER Routes induction air from filter to fuel metering device
Induction Manifold - ANSWER Connects all induction pipes to respective cylinders
3 purposes of the induction manifold - ANSWER - Warm fuel/air for atomization
- Cools engine oil
- Reduces induction icing
, Carburetor Air Temperature (CAT) - ANSWER Measures carbs temp for possible icing or
detonation
Where is the CAT located? - ANSWER Carb air inlet
What is the probable cause of an induction system leak after the carb? - ANSWER Lean
Mixture
What is the probable cause of an induction leak before the carb? - ANSWER Unfiltered
air
What is the probable casue of induction system icing on a fixed pitch prop aircraft? -
ANSWER Engine RPM decrease
What is the probable cause of induction system icing on a constant speed prop aircraft?
- ANSWER Decrease in MAP
Forced Induction - ANSWER Air induction by the use of mechanical force to increase
MAP at high altitudes
Turbine and compressor - ANSWER Exhaust flow drives turbine which drives compressor
to create forced induction of clean filtered air.
