Demo: SPL

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.

'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.

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.

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.

With the altimeter set to QFE, it shows height above the airfield. The other options are incorrect: they refer to elevation above sea level, pressure altitude, or the airfield's elevation, not the height above the airfield.

A too big equalizing tank causes the vertical speed indicator to show too high values, as the larger volume amplifies pressure changes. The other options are wrong: the instrument still works, is not overloaded, and does not show too low values.

Correct: The VSI measures the difference between instantaneous static pressure and previous static pressure, indicating vertical speed. The other options mention total or dynamic pressure, which are not used by the VSI.

Inclination is the angle between Earth's magnetic field lines and the horizontal plane. The other options refer to aircraft orientation, electrical interference, or the angle between magnetic and true north, none of which define inclination.

If the yaw string moves left in a right turn, the aircraft is slipping. To center the string, apply more rudder in the turn direction and reduce bank. The other options either do not correct the slip or make it worse.

If the yaw string moves left in a left turn, there is too much left rudder. Reducing rudder in the turn direction (with more bank) centers the string. More rudder or less bank worsen the slip, less rudder with less bank is not effective.

Damage to load-bearing parts always results in loss of airworthiness because it affects the aircraft's structural safety. A scratch in the paint, a crack in the cabin hood, or a dirty wing leading edge do not immediately compromise airworthiness.

The minimum speed increases by 18% because it rises with the square root of wing loading. A 40% increase means √1.4 ≈ 1.18, or 18%. The other answers are too high and ignore the square root relationship.

The correct answer is: With unchanged speed indication (IAS). Stall speed in IAS remains the same because the airspeed indicator measures dynamic pressure. The other options are wrong because neither decreased nor increased IAS nor extra speed is needed unless the POH requires it.

Touring Motor Gliders (TMG) mainly use 4-cylinder, 4-stroke engines because they are reliable, efficient, and suitable for continuous operation. 2-stroke, diesel, or Wankel engines are rare due to less suitability or higher maintenance.

If the static pressure lines are blocked, all three instruments—airspeed indicator, altimeter, and VSI—will show incorrect readings because they all rely on static pressure. The other errors affect only one instrument or are not relevant.

Maximum allowed airspeeds are found in the POH, often marked in the cockpit, and shown on the airspeed indicator. Approach charts, vertical speed indicators, AIP ENR, or briefing room postings do not provide this information.

The inclination is lowest at the magnetic equator because the Earth's magnetic field lines are parallel to the surface there. At the magnetic and geographic poles, inclination is highest. At the geographic equator, it is not necessarily zero.