Demo: PPL/H

Semi-monocoque construction uses frames and stringers with a load-bearing skin. Grid construction lacks a supporting skin, wood- or mixed construction refers only to materials, and honeycomb structure is a special lightweight design, not the described type.

Correct: two thin load-bearing layers and a light core material. This gives high strength with low weight. The other options are wrong because they mention thick layers or a heavy core, which would make the structure unnecessarily heavy.

The load factor 'n' is the ratio of lift to weight. It shows how much greater the lift is compared to the weight. The other options are incorrect because they compare forces not relevant to the load factor.

Sandwich structures offer low weight, high stiffness, high stability, and high strength because they combine lightweight cores with strong outer layers. The other options mention temperature durability or formability, which are not main features of sandwich structures.

Carbon fiber reinforced plastic has the highest strength due to its excellent tensile and bending properties. Wood, aluminium, and magnesium are less strong and are used where low weight or other features are more important.

If permissible limitations are exceeded, the aircraft must be inspected by a qualified engineer before the next flight. Only technical personnel can reliably assess possible damage, not pilots or instructors.

The hydraulic pump is driven by the main rotor gearbox, as it is directly linked to rotor movement. The engine only provides power, the alternator and additional aggregate serve other systems.

An aircraft moves about three axes: vertical, lateral, and longitudinal. These allow yaw, pitch, and roll. Options with two or four axes are incorrect, as only three exist. Terms like 'axis of speed' or 'axis of evil' are not correct for aircraft movement.

The pitch angle of helicopter rotor blades is controlled mechanically by control rods. Electric motors, cam rods, or electrical impulses are not used, as direct and precise control is required.

Moving the cyclic stick tilts the swash plate, which periodically changes the pitch angle of the rotor blades. The other options refer to collective changes, trim panels, or parts not directly affected by the cyclic stick.

Correct: The control mixing assembly overlays periodic and collective control inputs for main rotor pitch change. The other options refer to the freewheel, throttle, or hydraulic system, not the mixing assembly's function.

Correct: No open fires, obey smoking ban and apply ground cables. This prevents sparks and fire hazards. The other options are wrong because they suggest unsafe actions or ignore essential safety steps.

Tank ventilation prevents underpressure in the tank as fuel is consumed. Without it, fuel flow to the engine could be interrupted. The other options do not describe the real purpose of tank ventilation.

Electrical power is supplied by the battery and generator. Relays and circuit breakers only control or protect the system, but do not supply power. Therefore, only battery and generator is correct.

The correct answer is Watt, as electrical power is measured in watts. Ohm measures resistance, Volt measures voltage, and Ampere measures current. Only Watt is the unit for power.

Static dischargers discharge static electricity that builds up during flight. This prevents sparks and interference. The other options are incorrect: they do not ensure grounding during refueling, improve radio quality at altitude, or eliminate radio traffic interference.

Radio, navigation, and gyro instruments rely on electrical power. The magnetic compass, airspeed indicator, and altimeter work without electricity. Fuel gauges can be electric, but the artificial horizon is usually a gyro instrument.

Correct is 'First stroke - induction' because the intake valve is open and the mixture enters the cylinder. The other options are wrong: during compression, power, or exhaust, the intake valve is not open and the piston moves differently.

The correct answer is 'Second stroke - compression' because during compression, the piston moves up and compresses the mixture. 'Induction' has the piston moving down, 'power' follows ignition, and 'exhaust' opens the exhaust valve.

A defective sparking plug can cause the engine to run rough during the magneto check because it fails to ignite the mixture properly. The other options involve parts that do not directly affect engine running during this check.

Fuel must be checked for water content and impurities before starting, as condensation can form overnight. Carburettor heat, seat controls, and VHF are important, but fuel check is crucial after a cold night.

Condensation water collects at the lowest position in the tank because water is heavier than fuel and sinks. It does not float on the fuel, is not permanently mixed, and does not gather near the tank cap.

Avgas 100LL is blue to distinguish it from other aviation fuels. Green is for Avgas 100, Red for Avgas 80, and Yellow is not used for aviation gasoline.

The correct answer is to adjust the height in a hover, because carburettor heat reduces engine power. The other options (enriching the mixture, opening the vents, turning on the electric fuel pump) do not increase engine power in this situation.

During take-off, carburettor heating must be off because it reduces engine power. In other phases, the power loss is less critical, so heating can be used if needed.