Recording-2025-03-05T11_35_12.142Z

Airplane Engine Oil System

• Importance of Oil

  • Oil is essential for an airplane engine to operate effectively.

  • Functions of oil include:

    • Lubrication: Oil lubricates moving parts to reduce friction and wear.

    • Cooling: Helps to dissipate heat from the engine components.

    • Corrosion Protection: Provides a protective layer to prevent rust and corrosion.

    • Cleaning: Helps to remove dirt and other particles from the engine.

• Types of Oil Systems

  • Wet Sump System:

    • Example: Cessna 172.

    • Oil is stored in a tank located at the base of the engine.

    • Integrated with the engine, leading to simpler mechanics.

  • Dry Sump System:

    • Has a separate oil tank distinct from the engine.

    • Commonly used in high-performance aircraft for better oil circulation.

• Oil System Components

  • Strainer Screen:

    • Filters solid contaminants from the oil to protect the engine.

  • Oil Pump:

    • Moves oil from the sump to various components in the engine.

  • Oil Cooler:

    • Cools the oil if it is overheated; if not, it bypasses the cooler.

  • Oil Filter:

    • Removes further contaminants that may have passed through the strainer.

  • Return to Sump:

    • After lubricating and cooling, oil returns to the sump due to gravity.

• Oil Level Monitoring

  • Always check oil levels prior to flight according to the aircraft's flight manual.

  • Monitor oil pressure and temperature during flight; green arc indicates normal range.

  • Deviations may indicate potential engine problems including failure.

Fuel System Basics

• Delivery of Fuel to Engine

  • The fuel system is designed to transport fuel from tanks to the engine for combustion.

• Types of Fuel Systems

  • Gravity Fed Systems:

    • Common in high-wing aircraft like the Cessna 172 due to the tank being above the engine.

  • Fuel Pump Systems:

    • Used in low-wing aircraft where fuel tanks are at the same level or below the engine.

    • Includes an engine-driven pump and typically an electric backup pump.

  • Fuel Primer:

    • Some aircraft equipped with a fuel primer to inject fuel directly into the cylinder for easier engine starts, especially in cold weather.

• Components of the Fuel System

  • Fuel Tanks:

    • Generally located within the wings; filled from the top through gas caps.

    • Venting is needed to prevent vacuum as fuel is consumed.

  • Fuel Sensors:

    • Monitor fuel levels and provide information to the fuel gauge.

    • Critical to visually check for fuel quality and contaminants before flying.

  • Fuel Selector:

    • Controls which tank fuel is drawn from.

    • Positions include Left, Right, Both, and Off; critical during emergencies to stop fuel flow.

Hydraulic System Overview

• Functionality of the Hydraulic System

  • Requires hydraulic fluid for operating brakes, landing gear, and other systems.

• Components of a Typical Hydraulic System

  • Reservoir: Stores hydraulic fluid.

  • Pump: Moves hydraulic fluid to actuators.

  • Actuators: Convert fluid pressure into mechanical movement.

  • Brakes: Operated via hydraulic pressure; uses a pedal for control.

• Brake Mechanics

  • As the pilot presses on the brakes, the hydraulic fluid pushes a piston that squeezes the brake pads against the brake disc, slowing down the airplane.

Electrical System Fundamentals

• Electrical Power Distribution

  • Powers flight instruments, lights, flaps, and landing gear.

  • Usually a 14V or 28V direct current (DC) system comprising various components:

    • Alternator: Generates power and charges the battery.

    • Battery: Primarily used for starting the engine.

    • Circuit Breakers/Fuses: Protect the system from overload; circuit breakers are now preferred.

• Monitoring Electrical Power

  • Use of ammeter or load meter to gauge power supply and load between the alternator and battery.

Pitot Static System and Instruments

• Function of the Pitot Static System

  • Measures altitude, airspeed, and vertical speed using two pressure sources: the Pitot tube and static ports.

• Pitot Tube

  • Measures dynamic air pressure; typically located away from turbulence under the wing.

  • May feature a heating element to prevent ice blockage.

• Static Port

  • Measures static pressure unaffected by airflow; usually located on the airframe.

• Instruments

  • Altimeter: Displays altitude using aneroid wafers; adjusts for local atmospheric pressure.

  • Vertical Speed Indicator (VSI): Shows rate of climb/descent using pressure differential from static and diaphragm connections.

  • Airspeed Indicator: Combines inputs from both the Pitot tube and static ports for accurate speed readings.

• Importance of Accurate Measurements

  • Consistent monitoring and understanding of the aircraft’s performance metrics to maintain safety.