Aircraft General Knowledge
Airframe and systems
AGK rewards a systems picture rather than isolated facts. For each system ask: what is the power source, what does it drive, what happens on failure, and what indication does the pilot see? Hydraulics: reservoir, engine-driven and electric pumps, accumulator, filters, relief valve, selector, actuator. Electrics: battery, TRUs, alternators or generators, inverters, bus bars, protection. Pneumatics: engine bleed, HP/IP valves, pre-cooler, air-conditioning packs, pressurization outflow valve. Fuel: tanks, boost pumps, crossfeed, jettison where fitted, unusable fuel.
Engines
For piston engines know the four-stroke cycle, mixture control, detonation versus pre-ignition, and that the magneto check proves each ignition circuit separately. For gas turbines know N1 and N2, EGT limits, surge and stall, and why a high-bypass turbofan is efficient at moderate speed. With a constant-speed propeller the governor controls RPM by changing blade angle, and manifold pressure is the load indicator.
Traps
Multi-engine questions often ask what is lost when an engine fails - identify which pump, indication or duplication is affected. Instrument questions test the source: the attitude indicator and heading indicator are gyroscopic, not pitot-static. Beware reversals: an increase in EGT is not always a bad sign, but an uncommanded one is; oil pressure falling with temperature rising means trouble.
Worked example
Hydraulic actuator: 3,000 psi acting on a 2 square inch piston gives force = pressure × area = 6,000 lb. Halve the piston area and you halve the force; a failed pump does not remove stored pressure held in the accumulator.