Aircraft Systems - QT
Updated: Apr 20, 2021
Lesson Quicktakes cover the items that should be memorized from each of the wifiCFI Lessons. They do not cover all of the lesson details in-depth.
RECIPROCATING ENGINES
Back and forth motion of the pistons.
SPARK IGNITION
Spark provided by Spark Plugs.
COMPRESSION IGNITION
Spark provided by Compression.
CYLINDER ARRANGEMENTS:
Radial Engine = Cylinders in Radial Formation.
High Power to Weight Ratio.
In-Line Engine = Cylinders in Straight Line Formation.
Small frontal area.
Lower Power to Weight Ratio.
Less Cooling for Rear Cylinders.
V-Type Engine = Cylinders in V Formation.
More horsepower than In-Line.
Small frontal area.
Opposed Engine = Cylinder Oppose each other.
Most popular in aviation.
Lightweight and compact.
4 STROKE CYCLE
Intake Stroke = Suck.
Compression Stroke = Squeeze.
Power Stroke = Bang.
Exhaust Stroke = Blow.

PROPELLER TWIST
Created for uniform thrust along the entire length of the blades.
PROPELLER TYPES:
Fixed Pitch = Blade Angles are set and do not vary.
Climb Prop = Good at Climbing. Not at Cruising.
Cruise Prop = Good at Cruising. Not at Climbing.
Adjustable Pitch = Blade Angles can be varied on the ground with engine not running.
Constant Speed Prop = Blade Angles vary in flight to maintain constant RPM.
High Blade Pitch = Lower RPM (more drag).
Low Blade Pitch = Higher RPM (less drag).
ENGINE INDUCTION:
Carburetor System = Mixes Fuel and Air in Carburetor before being sent to Cylinders.
Slower throttle response.
Subject to Carburetor Icing.
Fuel Injection = Mixes Fuel and Air just prior to entering Cylinders.
Better fuel flow.
Faster throttle response.
Precise mixture control.
Better fuel distribution.
Vapor lock can cause difficult hot weather starts.
OIL SYSTEMS:
Wet Sump System = Oil is located in a sump that is integral with engine.
Dry Sump System = Oil is contained in a separate tank that is not integral with engine.
COWL FLAPS:
Open = Releases hot air from engine cowling and cools engine.
Closed = Traps hot air in engine cowling and heats engine.
COMBUSTION ISSUES:
Detonation = Uncontrolled/explosive ignition of fuel-air-mixture (not a smooth burn).

Pre-Ignition = Fuel-air-mixture detonates too early.

FUEL SYSTEMS:
Gravity Feed Systems = Gravity moves fuel from tanks to engine (high wing aircraft).
Fuel Pump Systems = Fuel is transferred to fuel tanks via fuel pumps (low wing aircraft).
FUEL GRADES:

GENERATORS VS ALTERNATORS
Generators = Produce DC power. May not produce enough power at low RPM settings.
Alternators = Produce AC power. Can output enough power through a large range of RPM settings.
FUSES VS CIRCUIT BREAKERS
Protect the electrical system from overload and overheating.
Fuses = When blown, must be replaced.
Circuit Breakers = When popped, may be reset.
AMMETER VS LOADMETER
Ammeters = Shows if the alternator/generator is producing an adequate supply of electrical power. Negative indications mean there is not enough power and system may be drawing off battery.
Loadmeter = Shows the load being placed on the alternator/generator.

HYDRAULIC SYSTEM:
Often used to operate wheel brakes and retractable landing gear.

LANDING GEAR TYPES:
Tricycle Type:
Better braking at higher speeds.
Better forward visibility.
Prevents ground looping.
Tailwheel Type:
Keeps prop higher off the ground (off airport operations).
More susceptible to ground looping.
ANTI-ICE AND DE-ICE SYSTEMS:
De-Ice Boots = Inflatable boots on leading edge of wing to break ice.
Heated Wing = Wing is heated to melt ice. Typically from engine bleed air.
Weeping Wing = Leaks TKS fluid over wing to prevent ice build up.