Demo: PPL/H

The altimeter uses an aneroid capsule that reacts with delay to pressure changes due to hysteresis. The vertical speed indicator and tachometer are less affected. The direct reading compass is not pressure-based and thus not affected.

Altitude measurement is based on static pressure, which decreases as altitude increases. Total, dynamic, and differential pressures are used for other instruments like the airspeed indicator, not the altimeter.

Correct: The vertical speed indicator measures the rate of change of static pressure by comparing current static pressure with that inside a reservoir. The other options are incorrect: they mention total pressure, vacuum, or acceleration, which are not how the instrument works.

The vertical speed indicator measures the difference between the present static pressure and the static pressure of a previous moment. This shows climb or descent rate. The other options are incorrect because they refer to dynamic or total pressure, which are not used by the VSI.

Calibrated airspeed (CAS) is indicated airspeed (IAS) corrected for instrument and position error. The other options are incorrect because they refer to different speeds or corrections not related to the definition of CAS.

TAS increases with altitude due to thinner air. You can estimate it by adding 2% of the CAS for every 1,000 ft. The other options are incorrect because they either subtract, use too high a percentage, or use the wrong unit (meters instead of feet).

The airspeed indicator shows indicated airspeed (IAS), which is lower than true airspeed (TAS) at 5000 ft. With 110 kt TAS at 5000 ft, IAS is about 100 kt. The other answers are too high or too low for this altitude and speed.

The airspeed indicator works by measuring total air pressure and comparing it to static air pressure. The other options are incorrect because they mention vacuum comparison, direct display, or only dynamic pressure, which do not describe the actual principle.

Red lines on instrument displays indicate operational limits, which must not be exceeded. Operational areas, caution areas, and recommended areas are usually marked with different colors or markings.

'Deviation' is correct because it refers to compass error caused by the aircraft's magnetic field. 'Variation' is the difference between true and magnetic north, 'declination' is another word for variation, and 'inclination' is the angle of magnetic field lines.

A magnetic compass deviates due to deviation (aircraft disturbances), turning and acceleration errors. Inclination/declination and variation relate to Earth's field, not the compass. Gravity and magnetism are not direct compass errors.

The airspeed indicator is connected to the pitot tube because it measures the dynamic pressure of incoming air. The altimeter and vertical speed indicator use static pressure, and the compass works independently of air pressure.

Altimeter, vertical speed indicator, and airspeed indicator use the static port to measure static air pressure. The direct-reading compass, slip indicator, and navigational computer do not use static pressure and are not connected to the static port.

The turn should be stopped at 270° on the magnetic compass, as this is the desired heading. The other values (240°, 360°, 300°) do not match the target heading and would result in an incorrect direction.

Static pressure is the pressure of undisturbed airflow, meaning the ambient air pressure unaffected by movement. Cabin pressure is unrelated. Pressure from orderly flow is dynamic pressure. The pitot tube measures total, not just static, pressure.

The correct answer is 210°. On the northern hemisphere, due to compass lag and turning errors, the magnetic compass overshoots when turning south. The turn should be stopped past the desired heading. The other options are too early or too late.

Dynamic pressure depends directly on air density and airflow speed squared, as given by q = ½·ρ·v². Air pressure, temperature, lift, and drag coefficients do not directly affect dynamic pressure.

A rotating gyro tends to maintain its position in space due to conservation of angular momentum. The other options are incorrect: it does not swing like a pendulum, move in shrinking circles, or simply follow the surrounding body’s movement.

The bank angle for a 2-minute turn depends on the true airspeed (TAS), as it reflects the actual speed through the air. IAS, CAS, and ground speed do not account for air density or wind, which are crucial for turn calculations.

A turn and bank coordinator shows the rate of turn (how fast the aircraft turns) and the coordination (whether the turn is slipping or skidding). The other answers are incorrect because the instrument does not show bank angle, pitch, or slip angle directly.

Amber (orange) alerts the pilot that corrective action may soon be needed. Red signals immediate danger, while blue and green indicate normal or auxiliary functions.

The caution area on the airspeed indicator is marked yellow, as it shows speeds safe only in smooth air. Red marks maximum speed, white is for flap operating range, and green is the normal operating range.

The HSI combines the directional gyro and the VHF navigation receiver to display heading and navigation info. The other options are incorrect because they either lack navigation data or do not include both required instruments.

Changing the altimeter from 1000 hPa to 1010 hPa shows about 80 m more, as each 1 hPa equals roughly 8 m. The other answers are incorrect because the difference is always about 80 m, not variable or zero.

The reference scale of the altimeter must be set before every flight and during cross-country flights, as air pressure changes frequently. The other options are incorrect because they do not specify the required frequency or correct timing for adjustment.