NCAA PPL Aircraft General Knowledge cheat sheet

Airframe structures: semi-monocoque construction carries loads through skin, stringers, and frames; the skin resists shear and tension while frames and stringers resist bending and compression, so a dent or crack in stressed skin is a structural concern, not cosmetic.

Primary flight controls are ailerons (roll), elevators (pitch), and rudder (yaw); trim tabs and balance tabs reduce control forces, while flaps increase lift and drag at lower airspeeds and typically have a published speed limit (VFE) that must not be exceeded.

Landing gear: fixed gear adds parasite drag; retractable gear requires a gear-up/down indicator and warning horn, and the maximum gear extension speed (VLE) and gear operating speed (VLO) are separate limitations - check both before cycling the gear.

Hydraulic systems transmit force via incompressible fluid; a typical light-aircraft system uses a reservoir, engine-driven pump, pressure relief valve, and selector valves, and loss of pressure affects gear, flaps, or brakes depending on what the system drives.

Electrical system: the battery supplies power for starting and emergency use; the alternator or generator carries the load in flight and recharges the battery. An ammeter shows current flow, and a failed alternator is indicated by a discharge reading with the battery draining.

Pitot-static system: the pitot tube supplies ram (impact) pressure, the static port supplies ambient pressure. Airspeed is the difference between them; the altimeter and vertical speed indicator use static pressure only, so a blocked static port freezes or errors all three instruments.

Gyroscopic instruments depend on rigidity in space (attitude indicator, heading indicator) and precession (turn coordinator, turn-and-slip indicator). Vacuum- or pressure-driven gyros spin down if the vacuum pump fails, so the turn coordinator is often electrically driven as a backup.

Powerplant: a normally aspirated piston engine produces power by converting fuel energy into mechanical work through the four strokes - intake, compression, power, exhaust. The mixture control adjusts fuel-to-air ratio, and the carburetor heat control prevents or clears carburetor ice by routing heated air into the induction system.

Engine instruments: tachometer shows RPM, manifold pressure gauge shows the absolute pressure in the intake manifold (inches of mercury), oil pressure and oil temperature gauges monitor lubrication, and the exhaust gas temperature (EGT) gauge is used to lean the mixture for best power or best economy.

Airframe structures: semi-monocoque construction carries loads through skin, stringers, and frames; the skin resists shear and tension while frames and stringers resist bending and compression, so a dent or crack in stressed skin is a structural concern, not cosmetic.

Primary flight controls are ailerons (roll), elevators (pitch), and rudder (yaw); trim tabs and balance tabs reduce control forces, while flaps increase lift and drag at lower airspeeds and typically have a published speed limit (VFE) that must not be exceeded.

Landing gear: fixed gear adds parasite drag; retractable gear requires a gear-up/down indicator and warning horn, and the maximum gear extension speed (VLE) and gear operating speed (VLO) are separate limitations - check both before cycling the gear.

Hydraulic systems transmit force via incompressible fluid; a typical light-aircraft system uses a reservoir, engine-driven pump, pressure relief valve, and selector valves, and loss of pressure affects gear, flaps, or brakes depending on what the system drives.

Electrical system: the battery supplies power for starting and emergency use; the alternator or generator carries the load in flight and recharges the battery. An ammeter shows current flow, and a failed alternator is indicated by a discharge reading with the battery draining.

Pitot-static system: the pitot tube supplies ram (impact) pressure, the static port supplies ambient pressure. Airspeed is the difference between them; the altimeter and vertical speed indicator use static pressure only, so a blocked static port freezes or errors all three instruments.

Gyroscopic instruments depend on rigidity in space (attitude indicator, heading indicator) and precession (turn coordinator, turn-and-slip indicator). Vacuum- or pressure-driven gyros spin down if the vacuum pump fails, so the turn coordinator is often electrically driven as a backup.

Powerplant: a normally aspirated piston engine produces power by converting fuel energy into mechanical work through the four strokes - intake, compression, power, exhaust. The mixture control adjusts fuel-to-air ratio, and the carburetor heat control prevents or clears carburetor ice by routing heated air into the induction system.

Engine instruments: tachometer shows RPM, manifold pressure gauge shows the absolute pressure in the intake manifold (inches of mercury), oil pressure and oil temperature gauges monitor lubrication, and the exhaust gas temperature (EGT) gauge is used to lean the mixture for best power or best economy.