Aircraft General Knowledge: Airframe, Systems and Powerplant
Airframe and flight controls
Understand the primary structure (fuselage, wings, empennage, landing gear) and how loads flow through the airframe. Know the difference between primary controls (aileron, elevator, rudder) and secondary effects (flaps, trim, spoilers), and be able to explain adverse yaw, differential ailerons, and why aileron drag increases on the downgoing wing.
Systems
Hydraulics: know Pascal's law, why systems are duplicated, and what happens on loss of pressure (usually a gear or flap extension by alternate means). Pneumatics and air conditioning: bleed air sources and the effect of bleed demand on engine performance. Electrical: bus architecture, generators versus battery, and which items are essential. Fuel: tank selection, unusable fuel, and the danger of unbalance. Ice and rain protection: de-ice versus anti-ice and the thermal limits on their use.
Powerplant
For piston engines, understand the four-stroke cycle, mixture control, detonation versus pre-ignition, and the effect of altitude on mixture. For turboprops and jets, know the gas turbine sections (intake, compressor, combustion, turbine, exhaust), the meaning of EGT/ITT and N1/N2, and why a compressor stall occurs.
Traps
Questions often test causation rather than description: for example, why carburettor ice forms at air temperatures well above freezing (venturi cooling plus fuel vaporisation). Another classic trap is confusing a system's normal and alternate modes, or assuming a warning light means the system has failed when it may indicate only a low level.
Rule of thumb
If a question describes a system losing pressure or power, first ask which services are essential and which have an alternate or gravity extension. That framing usually eliminates two answers immediately.