Aircraft General Knowledge: Airframe, Systems, Powerplant, Electrics
Airframe and flight controls
Understand the semi-monocoque structure, primary and secondary controls, trim systems, flaps and their effect on lift and drag, and the load limitations (limit and ultimate load factors). Know why gust loads and manoeuvring speed (VA) matter.
Powerplant
For a normally aspirated piston engine: induction, carburettor or fuel injection, mixture control, ignition with two magnetos, oil system functions (lubrication, cooling, sealing, cleaning), and cooling. Understand detonation versus pre-ignition, carburettor icing conditions, and the purpose of the carburettor heat control. Know fixed-pitch versus constant-speed propeller behaviour and manifold pressure limitations.
Systems and electrics
Fuel system: tanks, selector, primer, vents, and the danger of contamination and of running a tank dry. Electrical system: battery, alternator/generator, bus, master switch, fuses and circuit breakers, and what is lost if the alternator fails (load shedding). Pitot-static and vacuum systems: sources of error and failure indications.
Traps
Questions often reverse cause and effect: carburettor heat raises intake temperature but reduces power and can enrich the mixture; applying heat with ice already present may cause rough running before it clears. Another trap is confusing the ammeter reading with the voltmeter, or assuming the engine stops when the alternator fails.
Rule of thumb
Lean for cruise above roughly 3 000 ft density altitude; enrich before descent or high power. Apply carburettor heat whenever the temperature-dewpoint spread is small and humidity high, especially at low power settings.