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Aircraft General Knowledge

Q1: In a glider cockpit, the levers colored red, blue, and green correspond to which controls? ^t20q1

DE · FR

Answer

B)

Explanation

EASA standardises cockpit lever colours in gliders: red for the canopy hood (emergency) release, blue for speed brakes (airbrakes), and green for elevator trim. This colour coding ensures pilots can identify critical controls instantly under stress.

Key Terms

EASA = European Union Aviation Safety Agency

Source

Q2: Wing thickness is measured as the distance between the upper and lower surfaces of a wing at its ^t20q2

DE · FR

Answer

D)

Explanation

Wing thickness is defined as the maximum perpendicular distance between the upper and lower wing surfaces, measured at the thickest part of the airfoil cross-section (typically 20-30% of chord from the leading edge). This is the aerodynamically and structurally significant measurement.

Source

DE · FR

Answer

C)

Explanation

Grid (or truss/lattice) construction uses a framework of tubes or members to carry all structural loads, with the skin serving only as a fairing that does not contribute to structural strength.

Source

DE · FR

Answer

C)

Explanation

The primary structural members of a traditional fuselage are frames (also called formers or bulkheads, running circumferentially) and stringers (running longitudinally). Together they form the skeleton over which the skin is attached.

Source

DE · FR

Answer

D)

Explanation

Semi-monocoque construction uses both an internal framework (frames and stringers) AND a skin that actively bears structural loads (tension, compression, shear). This is the most common modern aircraft fuselage design.

Source

DE · FR

![](figures/AnatomysailplaneEN.png)

Answer

B)

Explanation

The tail assembly (empennage) consists of two principal structural groups: the horizontal tail (stabiliser and elevator, providing pitch stability and control) and the vertical tail (fin and rudder, providing yaw stability and control).

Source

DE · FR

Answer

D)

Explanation

A sandwich structure uses two thin, stiff face sheets (typically CFRP, glass fibre, or aluminium) bonded to a lightweight core (foam, balsa wood, or honeycomb). The thin skins carry bending loads while the light core resists shear and maintains separation, providing exceptional stiffness-to-weight ratio.

Source

DE · FR

Answer

C)

Explanation

Ribs are chordwise structural members that define the airfoil cross-section shape of the wing, running perpendicular to the spar. They establish the precise curvature of the upper and lower wing surfaces.

Source

DE · FR

Answer

B)

Explanation

The load factor n equals Lift divided by Weight (n = L/W). In straight and level flight, n = 1 (1g). In a banked turn, lift must exceed weight to maintain altitude -- for example, in a 60-degree bank, n = 2 (2g). Load factor is critical for glider structural design, as exceeding maximum positive or negative g-limits risks structural failure.

Key Terms

Source

Q10: What are the key benefits of sandwich construction? ^t20q10

DE · FR

Answer

B)

Explanation

Sandwich construction excels at combining low weight with high stiffness, stability, and strength -- the ideal combination for aerospace applications. The bending stiffness increases dramatically when stiff face sheets are spaced apart by a lightweight core.

Source

DE · FR

Answer

C)

Explanation

Carbon fibre reinforced plastic (CFRP) has exceptional strength-to-weight ratio with tensile strength exceeding steel at a fraction of the weight. Modern high-performance gliders are predominantly CFRP.

Key Terms

D — Drag

Source

DE · FR

Answer

C)

Explanation

The trim system adjusts the elevator trim tab (or spring trim) to hold a desired pitch attitude without continuous pilot input on the control stick, reducing elevator stick force to zero at the trimmed speed.

Source

Q13: Structural damage to a fuselage may result from ^t20q13

DE · FR

Answer

C)

Explanation

Exceeding manoeuvring speed (VA) in turbulent conditions can cause structural damage because gusts impose sudden load factors that may exceed the design limit. VA is the speed at which a full control deflection or maximum gust will not exceed the structural limit load.

Key Terms

VA = Manoeuvring Speed

Source

DE · FR

Answer

C)

Explanation

An aircraft rotates about three principal axes passing through the centre of gravity: the longitudinal axis (nose to tail -- roll), the lateral axis (wingtip to wingtip -- pitch), and the vertical axis (top to bottom -- yaw).

Source

DE · FR

![](figures/AnatomysailplaneFR.png)

Answer

D)

Explanation

Ailerons control roll -- rotation around the longitudinal axis. When one aileron deflects up and the other down, differential lift rolls the aircraft.

Source

Q16: On a small single-engine piston aircraft, how are the flight controls typically operated and connected? ^t20q16

DE · FR

Answer

C)

Explanation

Small piston aircraft and gliders use direct mechanical linkages -- push-pull rods and steel control cables -- to transmit pilot input directly to control surfaces. This is simple, lightweight, and reliable with no power source required.

Key Terms

D — Drag

Source

DE · FR

Answer

A)

Explanation

Left rudder primarily yaws the nose left around the vertical axis. The secondary effect is roll to the left: as the nose yaws left, the outer (right) wing moves faster and generates more lift while the inner (left) wing slows and generates less, creating a bank to the left.

Source

DE · FR

Answer

A)

Explanation

Pulling back on the stick deflects the elevator upward, increasing the downward aerodynamic force on the tail. With the tail pushed down, the nose pivots up around the lateral axis through the centre of gravity. This seems counterintuitive but is correct: tail goes down, nose goes up.

Source

DE · FR

![](figures/AnatomysailplaneEN.png)

Answer

C)

Explanation

The three primary flight controls are elevator (pitch), rudder (yaw), and aileron (roll). These directly control rotation about the aircraft's three axes.

Key Terms

D — Drag

Source

DE · FR

Answer

C)

Explanation

Secondary flight controls (trim tabs, flaps, speedbrakes, slats) enhance aircraft performance and reduce pilot workload. Trim neutralises stick forces; flaps increase low-speed lift; speedbrakes manage descent rate.

Source

DE · FR

Answer

D)

Explanation

Moving trim aft commands nose-up trim. The trim tab deflects downward, generating an aerodynamic force that pushes the elevator trailing edge upward. The raised elevator pushes the tail down and raises the nose. Trim tabs always move opposite to the elevator: tab down causes elevator up.

Source

DE · FR

![](figures/AnatomysailplaneEN.png)

Answer

D)

Explanation

For nose-up trim, the trim tab deflects downward. The downward tab creates an aerodynamic force pushing the elevator trailing edge up, which holds the elevator in a nose-up position without pilot input.

Key Terms

CG = Centre of Gravity

Source

DE · FR

Answer

C)

Explanation

Trim adjusts control forces so the pilot can fly hands-off at the trimmed speed and attitude. It neutralises the stick force to zero at the desired condition.

Key Terms

CG = Centre of Gravity

Source

DE · FR

Answer

D)

Explanation

The Pitot-static system measures total pressure (from the Pitot tube facing the airflow) and static pressure (from flush static ports on the fuselage). These feed the ASI, altimeter, and variometer.

Source

DE · FR

Answer

B)

Explanation

The Pitot tube faces into the airflow and senses total pressure (stagnation pressure), which equals static pressure plus dynamic pressure (q = 1/2 rho v-squared).

Key Terms

Source

Q26: QFE refers to the ^t20q26

DE · FR

Answer

C)

Explanation

QFE is the atmospheric pressure at a specific reference point, typically the runway threshold. Setting QFE on the altimeter causes it to read zero on the ground at the aerodrome, showing height above the field during flight.

Key Terms

Source

Q27: What is the function of the altimeter subscale? ^t20q27

DE · FR

Answer

C)

Explanation

The altimeter subscale (Kollsman window) lets the pilot set a reference pressure: QNH for altitude above sea level, QFE for height above the airfield, or 1013.25 hPa for flight levels.

Key Terms

Source

DE · FR

Answer

C)

Explanation

Setting a higher pressure than actual QNH causes the altimeter to over-read -- it shows a higher altitude than the aircraft's true position. The aircraft is actually closer to the ground than indicated, creating a dangerous terrain clearance illusion. The memory aid: "High to Low, look out below.

Key Terms

Source

Q29: A temperature lower than the ISA standard may cause ^t20q29

DE · FR

Answer

A)

Explanation

In colder-than-standard air, the atmosphere is denser and pressure drops faster with altitude than ISA assumes. The altimeter over-reads, indicating a higher altitude than the aircraft's actual position -- the pilot is lower than they think. "Cold air = lower than you think.

Key Terms

Source

DE · FR

Answer

B)

Explanation

A flight level is a pressure altitude expressed in hundreds of feet with the altimeter set to 1013.25 hPa (standard pressure). FL100 = 10,000 ft on standard setting. All aircraft above the transition altitude use this common datum for vertical separation regardless of local pressure variations.

Key Terms

Source

Q31: True altitude is defined as ^t20q31

DE · FR

Answer

C)

Explanation

True altitude is the actual geometric height of the aircraft above mean sea level (MSL), obtained by correcting indicated altitude for deviations from the ISA temperature profile. The altimeter assumes standard ISA conditions; when actual temperature differs, the indicated reading diverges from the real MSL height.

Key Terms

Source

Q32: When flying in air colder than ISA, the indicated altitude is ^t20q32

DE · FR

Answer

D)

Explanation

In colder-than-ISA air the atmosphere is denser, so pressure decreases more rapidly with altitude than the altimeter assumes. The altimeter therefore over-reads and shows a higher value than the aircraft's actual MSL height — the aircraft is physically lower than the instrument indicates. This is a serious terrain clearance hazard, summarized by the memory aid "High to low (temperature), look out below." B states the opposite of what occurs.

Key Terms

Source

DE · FR

Answer

C)

Explanation

The altimeter is calibrated to the ISA standard temperature lapse rate. When the actual temperature exactly matches ISA and the correct QNH is set, all instrument assumptions are perfectly met and no error exists — indicated altitude equals true altitude. This is the ideal baseline condition from which deviations introduce errors. A and B describe situations with non-standard temperature or pressure.

Key Terms

Source

DE · FR

Answer

C)

Explanation

Hysteresis error affects the altimeter because its aneroid capsules — thin elastic bellows that expand and contract with pressure changes — do not return to exactly the same position when pressure is restored to a previously experienced value. This mechanical lag means the altimeter may show slightly different readings at the same altitude when climbing versus descending.

Source

DE · FR

Answer

C)

Explanation

Static pressure is the ambient atmospheric pressure that decreases predictably with altitude according to the ISA model. The altimeter senses this pressure via the static port and converts it to an altitude reading using calibrated aneroid capsules.

Key Terms

ISA = International Standard Atmosphere

Source

Q36: How does a vertical speed indicator work? ^t20q36

DE · FR

Answer

B)

Explanation

The VSI detects rate of climb or descent by comparing current static pressure (from the static port) against a reference pressure stored in an internal reservoir that communicates via a calibrated leak. When climbing, static pressure drops faster than the reservoir can equalize, creating a pressure difference that deflects the pointer proportional to climb rate. - A describes the ASI operating principle (total minus static = dynamic). - C describes an accelerometer. - D describes a barometer, which cannot indicate a rate of change. Only B correctly explains VSI operation.

Source

Q37: The vertical speed indicator compares the pressure difference between ^t20q37

DE · FR

![](figures/t20_q37.png)

Answer

B)

Explanation

The VSI senses only static pressure, which changes as altitude changes. It compares the instantaneous static pressure arriving through the static port with the slightly delayed static pressure stored in the metering reservoir behind the calibrated restriction. The rate of pressure change indicates the rate of altitude change.

Source

Q38: An aircraft flies on a heading of 180° at 100 kt TAS. The wind blows from 180° at 30 kt. Ignoring instrument and position errors, what will the airspeed indicator approximately show? ^t20q38

DE · FR

Answer

D)

Explanation

The ASI measures the aircraft's speed relative to the surrounding air mass, not relative to the ground. The aircraft moves through the air at 100 kt TAS, so the ASI shows 100 kt regardless of wind. A wind from 180° on a heading of 180° is a headwind, reducing ground speed to 70 kt — that is A, but ground speed is not what the ASI reads.

Key Terms

TAS = True Airspeed

Source

DE · FR

Answer

D)

Explanation

The ASI compares total pressure from the Pitot tube (which captures all air pressure including the motion component) against static pressure from the static port (ambient pressure only). The difference is dynamic pressure (q = ½ρv²), proportional to airspeed squared — the expanding capsule converts this into an IAS reading. - A describes a simple barometer.

Key Terms

Source

Q40: Red lines on instrument displays typically mark which values? ^t20q40

DE · FR

Answer

C)

Explanation

Red radial marks on aircraft instruments indicate absolute operational limits that must never be exceeded — such as VNE (never-exceed speed) on the ASI. These represent structural or aerodynamic boundaries beyond which catastrophic failure or loss of control may occur.

Key Terms

VNE = Never Exceed Speed

Source

DE · FR

Answer

B)

Explanation

IAS is derived from dynamic pressure, which equals total pressure (Pitot tube) minus static pressure (static port). The ASI capsule deflects in proportion to this pressure difference and the needle indicates IAS.

Key Terms

IAS = Indicated Airspeed

Source

Q42: What does the red line on an airspeed indicator represent? ^t20q42

DE · FR

Answer

C)

Explanation

The red line marks VNE — Velocity Never Exceed — the absolute structural speed limit that must not be exceeded under any circumstances, including smooth air. Beyond VNE, the risk of aeroelastic flutter or catastrophic structural failure is unacceptable. - A describes the upper boundary of the yellow arc (caution range), where turbulence must be avoided. - B describes VFE (flap extension speed), marked by the top of the white arc.

Key Terms

VNE = Never Exceed Speed

Source

Q43: The compass error produced by the aircraft's own magnetic field is known as ^t20q43

DE · FR

Answer

B)

Explanation

Deviation is the compass error caused by the aircraft's own magnetic fields — from steel structures, electrical wiring, and electronic equipment on board. It varies with the aircraft's heading and is tabulated on the compass deviation card after a compass swing.

Source

Q44: What errors cause a magnetic compass to deviate from magnetic north? ^t20q44

DE · FR

Answer

D)

Explanation

Three instrument errors cause the magnetic compass to deviate from magnetic north: deviation (from the aircraft's own magnetic fields), turning errors (the compass card tilts due to magnetic dip during turns, especially on northerly/southerly headings), and acceleration errors (speed changes on easterly/westerly headings produce false readings due to the same dip effect). - A incorrectly includes variation, which is a geographic property of Earth, not an instrument error.

Source

Q45: Which cockpit instrument receives input from the Pitot tube? ^t20q45

DE · FR

Answer

C)

Explanation

Only the airspeed indicator is connected to the Pitot tube, which supplies total pressure as one of the two inputs needed to compute IAS.

Key Terms

IAS = Indicated Airspeed

Source

Q46: An aircraft in the northern hemisphere turns from 270° to 360° via the shortest route. At roughly what compass indication should the pilot stop the turn? ^t20q46

DE · FR

Answer

C)

Explanation

The shortest turn from 270° to 360° is a right turn through northwest toward north. In the northern hemisphere, magnetic dip causes the compass to lead (read ahead of the actual heading) when turning toward north, so the pilot must stop early — before the compass reaches 360°. The rule of thumb is to stop approximately 30° before the target when turning to north: 360° − 30° = 330°.

Source

DE · FR

Answer

A)

Explanation

All three Pitot-static instruments receive static pressure: the altimeter (converts static pressure to altitude), the vertical speed indicator (compares current and stored static pressure to show climb/descent rate), and the airspeed indicator (uses static pressure alongside Pitot total pressure). The direct-reading compass in B and D is a self-contained magnetic instrument with no pneumatic input. The slip indicator in B and C is an inertial/gravity instrument (a ball in liquid) that requires no connection to the static port.

Source

Q48: An aircraft in the northern hemisphere turns from 360° to 270° via the shortest route. At approximately what compass reading should the turn be stopped? ^t20q48

DE · FR

Answer

D)

Explanation

The shortest turn from 360° (north) to 270° (west) is a left turn passing through northwest and west. On westerly headings in the northern hemisphere, the magnetic dip-induced turning error is minimal because the compass card tilts most significantly near north and south, not near east and west. At 270° the compass reads with acceptable accuracy, so the pilot should stop the turn when the compass shows 270°.

Source

DE · FR

Answer

C)

Explanation

Static pressure is the ambient atmospheric pressure of undisturbed air, exerted equally in all directions at a given altitude regardless of airflow velocity. It is measured by flush static ports positioned on the fuselage where local aerodynamic disturbance is minimized.

Source

Q50: An aircraft in the northern hemisphere turns from 030° to 180° via the shortest route. At approximately what compass heading should the turn be ended? ^t20q50

DE · FR

Answer

B)

Explanation

The shortest turn from 030° to 180° is a right turn through east and south. When turning toward southerly headings in the northern hemisphere, the compass lags — it under-reads the actual heading and shows a smaller value than the aircraft has actually turned through. The pilot must therefore overshoot: continue turning until the compass reads approximately 180° + 30° = 210°, at which point the actual heading is approximately 180°.

Source

DE · FR

Answer

D)

Explanation

EASA color coding assigns red to the emergency canopy release lever in gliders, because red is universally associated with critical safety and emergency functions, allowing the pilot to locate it instantly during an accident scenario. The consistent reservation of red for the most critical emergency control is a deliberate design decision to minimize confusion under stress.

Key Terms

EASA = European Union Aviation Safety Agency

Source

Q52: During winter maintenance, you notice honeycomb elements inside the fuselage. What construction category does this glider belong to? ^t20q52

DE · FR

Answer

C)

Explanation

Honeycomb core material is the defining hallmark of modern composite sandwich construction. Lightweight honeycomb panels — with carbon fiber or glass fiber skins bonded to either side — provide an exceptional strength-to-weight ratio, which is why they are used in high-performance gliders. The presence of honeycomb elements unambiguously identifies C.

Source

Q53: The Discus B has its horizontal stabilizer mounted at the top of the fin. What type of tail configuration is this? ^t20q53

DE · FR

Answer

C)

Explanation

When the horizontal stabilizer is mounted at the top of the vertical fin, the silhouette viewed from the front forms a "T" shape — hence the name T-tail. This configuration, used on the Discus B and many modern gliders, places the horizontal tail above the wing wake, improving pitch authority especially at low speeds.

Source

Q54: What is the role of the fixed vertical fin and fixed horizontal stabilizer on a glider's tail? ^t20q54

DE · FR

![](figures/AnatomysailplaneEN.png)

Answer

C)

Explanation

The fixed tail surfaces — horizontal stabilizer and vertical fin — provide static stability in pitch and yaw. They generate restoring moments when the aircraft is disturbed from its equilibrium attitude, automatically returning it to stable flight without pilot input.

Source

Q55: During winter maintenance, the equipment officer explains the CG-mounted tow hook mechanism. Why must it release the cable automatically? ^t20q55

DE · FR

Answer

D)

Explanation

As the glider nears the top of its winch-launch arc and begins to converge with the winch position, the cable angle reverses abruptly from a forward pull to a downward pull — if still attached, this causes a violent pitch-up that is likely fatal. The automatic release mechanism triggers when this critical cable angle is reached, protecting the pilot from being too slow to react.

Key Terms

CG = Centre of Gravity

Source

Q56: Aileron deflection produces rotation around which axis? ^t20q56

DE · FR

Answer

D)

Explanation

Ailerons produce roll — rotation around the longitudinal axis, which runs from the aircraft's nose to its tail. Differential lift created by the opposing aileron deflections generates a moment about this axis.

Source

Q57: When the control stick is moved to the left, what happens? ^t20q57

DE · FR

Answer

D)

Explanation

Moving the stick left commands a left roll. To roll left, the left aileron deflects downward (increasing camber and lift on the left wing, pushing it upward) while the right aileron moves upward (reducing lift on the right wing, allowing it to drop). This differential lift rolls the aircraft to the left. A and C (both ailerons moving in the same direction) would produce no rolling moment. - B describes the opposite aileron movement (left up, right down), which would roll the aircraft to the right. Only D is correct.

Source

Q58: In mechanical brake systems, how is the braking force transmitted from the pedals or handles to the brake shoes? ^t20q58

DE · FR

Answer

D)

Explanation

Glider mechanical brake systems transmit braking force from the pilot's pedal or hand lever to the brake shoes via a mechanical linkage of cables and pushrods — no fluid, compressed air, or electricity is required. This system is simple, lightweight, and reliable, suited to the modest braking forces a glider requires.

Source

Q59: The flight manual states that the glider has balanced control surfaces. What is the main reason for this design? ^t20q59

DE · FR

Answer

C)

Explanation

Mass-balancing a control surface — placing counterweights forward of the hinge axis — moves the surface's center of gravity to its pivot line, eliminating the inertial coupling between aerodynamic loads and structural oscillations that produces aeroelastic flutter. Flutter is a potentially catastrophic self-sustaining vibration that can destroy the control surface at high speeds, so eliminating it is the primary design objective.

Source

DE · FR

Answer

A)

Explanation

The small flush-mounted orifices on the fuselage sides are the static pressure ports of the Pitot-static system. They sense ambient atmospheric (static) pressure and transmit it via internal flexible tubing to the altimeter, variometer, and airspeed indicator. Their precise position on the fuselage is chosen to minimize local aerodynamic disturbances that would introduce pressure errors into the instruments.

Source

Q61: Which instrument receives its input from the Pitot tube? ^t20q61

DE · FR

Answer

D)

Explanation

The airspeed indicator is the only cockpit instrument connected to the Pitot tube, which supplies it with total pressure. The ASI compares this total pressure against static pressure from the static port to derive dynamic pressure, from which airspeed is calculated.

Source

Q62: If the altimeter subscale is set to a higher pressure without any actual pressure change, how does the reading change? ^t20q62

DE · FR

Answer

A)

Explanation

When the subscale is set to a higher reference pressure without any change in actual atmospheric pressure, the altimeter indicates a higher altitude. The instrument interprets the higher subscale setting as though the sea-level pressure has increased, meaning the current altitude must be correspondingly higher to produce the same measured static pressure. The reading always increases when a higher pressure is dialed in.

Source

Q63: If the static pressure port is blocked by ice during a descent, what does the variometer show? ^t20q63

DE · FR

Answer

C)

Explanation

When the static port is blocked by ice, the static pressure reaching the variometer remains frozen at the last value before blockage. Both sides of the variometer's measuring system receive the same trapped pressure, so no pressure difference develops. The instrument therefore reads zero regardless of whether the aircraft is actually climbing or descending. A (descent) and B (climb) would require changing static pressure inputs.

Source

Q64: The red line on the airspeed indicator marks VNE. Is exceeding this speed ever permitted? ^t20q64

DE · FR

Answer

C)

Explanation

VNE (Velocity Never Exceed) is an absolute structural limit that must never be exceeded under any circumstances, by any amount, for any duration. Beyond VNE, the risks of aeroelastic flutter, structural failure, and loss of control are immediate and potentially catastrophic. Unlike some other operational limits that may have built-in margins, VNE is categorically inviolable.

Key Terms

VNE = Never Exceed Speed

Source

Q65: Switching on the radio in a glider consistently causes the magnetic compass to rotate in the same direction. Why? ^t20q65

DE · FR

Answer

D)

Explanation

When the radio operates, it generates an electromagnetic field. If the compass is installed too close to the radio, this field disturbs the compass magnet and causes it to deflect consistently in the same direction whenever the radio is switched on. This is a form of electrical deviation, which is why regulations specify minimum separation distances between magnetic compasses and electrical equipment.

Source

Q66: What information does FLARM provide? ^t20q66

DE · FR

Answer

C)

Explanation

FLARM (Flight Alarm) is an anti-collision system that provides two categories of alerts: nearby FLARM-equipped aircraft regardless of altitude or collision risk, and fixed obstacles such as power lines, cable car wires, and antennas stored in its internal database. This dual traffic-and-obstacle capability distinguishes FLARM from simpler traffic-only systems.

Key Terms

D — Drag

Source

Q67: Your glider has an ELT with a toggle switch offering ON, OFF, and ARM modes. Which setting enables automatic distress signal transmission upon a violent impact? ^t20q67

DE · FR

Answer

C)

Explanation

ARM mode activates the ELT's internal G-switch (impact sensor), which automatically triggers the distress signal transmission on 406 MHz and 121.5 MHz upon detecting a crash-level deceleration. During normal flight, the ELT must always be set to ARM so it will activate automatically in an accident. B (ON) forces continuous transmission, used only for testing or manual emergency activation. A (OFF) completely disables the ELT.

Key Terms

ELT = Emergency Locator Transmitter

Source

Q68: Electric current is measured in which unit? ^t20q68

DE · FR

Answer

D)

Explanation

Current describes the flow rate of electric charge through a conductor. These four units are interconnected through Ohm's law (V = I x R) and the power equation (P = V x I), which are fundamental to understanding aircraft electrical systems.

Key Terms

Source

Q69: During a pre-flight check, you discover the battery fuse is defective and the electrical instruments are inoperative. Would it be acceptable to bridge the fuse with aluminum foil from a chocolate wrapper? ^t20q69

DE · FR

Answer

C)

Explanation

Replacing a fuse with aluminum foil is strictly prohibited and extremely dangerous. A fuse is a precisely rated protection device designed to melt at a specific current, protecting the wiring and instruments from overcurrent damage. Aluminum foil has no defined current rating and will not interrupt the circuit during a short circuit, allowing excessive current to flow and potentially causing an electrical fire or destroying equipment. The aircraft must not fly until a proper fuse is installed.

Source

Q70: What is the primary disadvantage of the VHF frequency band used in aviation radio communications? ^t20q70

DE · FR

Answer

B)

Explanation

The primary limitation of VHF radio communications is that VHF waves propagate in straight lines (quasi-optical propagation) and do not follow the Earth's curvature. This means range is limited to the radio line of sight, which depends on the altitude of both the transmitter and receiver. At low altitude, range is significantly reduced.

Key Terms

VHF = Very High Frequency

Source

Q71: Which instrument is connected to the Pitot tube? ^t20q71

DE · FR

Answer

C)

Explanation

The airspeed indicator is the only instrument that receives total pressure input from the Pitot tube. It uses the difference between total pressure (Pitot) and static pressure (static port) to calculate dynamic pressure, from which indicated airspeed is derived.

Source

Q72: What is the standard colour of aviation oxygen cylinders? ^t20q72

DE · FR

Answer

C)

Explanation

Under the older European convention (pre-EN 1089-3), oxygen cylinders had a black body with a white shoulder — that is the answer this exam expects.

However, the current European standard EN 1089-3 (fully transitioned by 2025) specifies white body + white shoulder (RAL 9010) for all oxygen cylinders, including aviation breathing oxygen. In practice, both black (legacy) and white (new standard) cylinders are still encountered in the field.

Note: If you encounter this question on the actual exam, answer black (the legacy convention the exam bank uses). In real life, oxygen cylinders are increasingly white per EN 1089-3.

Source

Q73: During a turn, what does the ball (inclinometer) indicate? ^t20q73

DE · FR

Answer

D)

Explanation

The ball (inclinometer) indicates the direction of the resultant force from the combination of gravity (weight) and centrifugal force acting on the aircraft during a turn. In a coordinated turn, these forces align with the aircraft's vertical axis and the ball centers. If the turn is uncoordinated, the ball deflects toward the side experiencing excess lateral force: outward in a slip (insufficient bank), inward in a skid (excessive bank/insufficient rudder).

Source

Q74: Why must the equipped weight of a glider pilot exceed a specified minimum value? ^t20q74

DE · FR

Answer

C)

Explanation

The minimum pilot weight requirement exists to ensure the aircraft's center of gravity stays within the approved forward and aft limits. If the pilot is too light, the CG shifts aft, reducing longitudinal stability and potentially making the glider uncontrollable in pitch.

Key Terms

CG = Centre of Gravity

Source

Q75: What is the purpose of a glider's flight manual (AFM)? ^t20q75

DE · FR

Answer

D)

Explanation

The Aircraft Flight Manual (AFM) is the official regulatory document that provides the pilot with all information needed for safe operation: operating limitations (speeds, load factors, weight limits), normal and emergency procedures, performance data, and weight and balance information. - A describes the maintenance logbook, not the AFM.

Source

Q76: What does the automatic regulator on an oxygen system do? ^t20q76

DE · FR

Answer

A)

Explanation

The automatic regulator on an on-demand oxygen system performs two key functions: it adjusts the air-to-oxygen mixture ratio according to altitude (higher altitudes require a richer oxygen mix to maintain adequate partial pressure), and it delivers oxygen only during inhalation, conserving the supply. This is far more efficient than continuous-flow systems. - B describes a simple pressure reducer, not an automatic regulator. C and D describe partial functions but miss the altitude-dependent mixture adjustment and the on-demand delivery mechanism.

Source

Q77: What is a compensated variometer? ^t20q77

DE · FR

Answer

D)

Explanation

A compensated variometer (total energy compensated variometer or TE variometer) eliminates false climb and sink indications caused by the pilot's control inputs such as pulling up or pushing over. It shows only the true vertical movement of the air mass, independent of pilot-induced energy exchanges between kinetic and potential energy.

Source

Q78: Up to what bank angle can the magnetic compass be considered reliable? ^t20q78

DE · FR

Answer

B)

Explanation

The magnetic compass is generally considered reliable up to approximately 30 degrees of bank angle. Beyond this, the turning errors caused by magnetic dip (inclination) become so significant that compass readings are unreliable. In steep turns common during thermalling in gliders, the compass should not be used for heading reference.

Source

Q79: A glider fitted with an ELT is being stored in the hangar. What should you do? ^t20q79

DE · FR

Answer

C)

Explanation

When storing a glider with an ELT in the hangar, the pilot must verify that the ELT is not inadvertently transmitting on 121.5 MHz (the international distress frequency). Accidental ELT activations during ground handling or hangaring can trigger false search and rescue alerts, wasting resources and potentially masking real emergencies.

ELT switch positions: ON = actively transmitting (emergencies only), ARM = armed with crash sensor (correct setting during flight), OFF = fully disabled (correct setting during hangar storage). When hangaring, set the ELT to OFF to prevent false triggers from ground handling, then verify no accidental transmission on 121.5 MHz.

Key Terms

ELT = Emergency Locator Transmitter

Note: An ELT is not the same as FLARM. ELT transmits a distress signal on 121.5 MHz after a crash; FLARM is a collision avoidance system. Most gliders in Switzerland/Germany have FLARM but not necessarily an ELT. This question applies where ELT is fitted.

Source

Q80: What does the green arc on a glider's airspeed indicator represent? ^t20q80

DE · FR

Answer

B)

Explanation

The green arc on a glider's ASI indicates the normal operating speed range, within which the aircraft can be flown in all conditions including turbulence with full control deflection. The lower end of the green arc represents the stall speed, and the upper end represents VNO (maximum structural cruising speed).

Key Terms

Source

Q81: Why must a compass be compensated (swung)? ^t20q81

DE · FR

Answer

C)

Explanation

A compass swing (compensation procedure) is performed to minimize deviation errors caused by the aircraft's own metallic components and electromagnetic fields from onboard electrical equipment. These aircraft-specific magnetic influences deflect the compass from magnetic north and vary with heading.

Source

Q82: When two release hooks are fitted, which hook must be used for aerotow takeoff? ^t20q82

DE · FR

Answer

C)

Explanation

For aerotow takeoff, the nose hook (Bugkupplung) must always be used. The nose hook provides passive directional stability: any lateral deviation generates a natural restoring moment pulling the glider back into line behind the tug.

Rule: Standard procedure: Aerotow = nose hook. Winch launch = CG hook. However, some gliders are approved for CG hook aerotow per their AFM - this requires more active piloting as the CG hook provides no passive directional stability.

Safety warning: Never use the nose hook for winch launch. The nose hook has no automatic release mechanism. If the cable fails to release at the top of the arc, the glider is pulled nose-down with no recovery possible - this is a fatal scenario. The CG hook's spring-loaded automatic release is specifically designed to prevent this.

Key Terms

CG = Centre of Gravity

Source

Q83: A glider pilot weighs 110 kg equipped; the glider has an empty weight of 250 kg. How much water ballast can be loaded? See attached sheet. ^t20q83

DE · FR

![](figures/t20_q90.png)

Answer

C)

Explanation

Using the loading table from the flight manual (attached sheet): with an empty weight of 250 kg and a pilot equipped weight of 110 kg, the total so far is 360 kg. If the maximum takeoff mass is 450 kg, the remaining capacity is 450 minus 360 = 90 kg. Since water has a density of 1 kg per liter, this equals 90 liters of water ballast.

Source

Q84: When is the use of weak links on tow ropes mandatory? ^t20q84

DE · FR

Answer

C)

Explanation

The use of weak links (fusible links or Sollbruchstellen) on tow ropes is mandatory in all cases, regardless of rope material or glider type. Weak links are calibrated breaking elements that protect both the glider and the tow aircraft (or winch system) from excessive loads by failing at a predetermined force. The protection they provide is essential for all launch configurations.

Source

Q85: What does the yellow triangle on a glider's airspeed indicator signify? ^t20q85

DE · FR

Answer

C)

Explanation

The yellow triangle on a glider's ASI marks the recommended approach speed for landing under normal conditions. This is the reference speed the pilot should target on final approach, typically 1.3 to 1.5 times the stall speed, providing an adequate safety margin above stall while ensuring a reasonable landing distance.

Key Terms

VNO = Maximum Structural Cruising Speed

Source

Q86: What constitutes a glider's minimum equipment? ^t20q86

DE · FR

Answer

A)

Explanation

The minimum equipment required for a glider is defined in its specific flight manual (AFM/POH). There is no universal one-size-fits-all list; each aircraft type has its own minimum equipment requirements specified by the manufacturer and approved by the certification authority.

Source

Q87: Are the instruments shown in the diagram connected correctly? ^t20q87

DE · FR

![](figures/t20_q87.png)

Answer

D)

Explanation

The diagram shows standard Pitot-static system connections: the Pitot tube feeds total pressure to the airspeed indicator, and the static port feeds static pressure to the altimeter, variometer, and also to the static side of the airspeed indicator. When all connections follow this standard configuration, the instruments are correctly connected.

Source

Q88: What does the red radial mark on a glider's airspeed indicator signify? ^t20q88

DE · FR

Answer

D)

Explanation

The red radial mark on a glider's ASI indicates VNE (Velocity Never Exceed), the absolute maximum speed that must never be exceeded under any conditions. Exceeding VNE can lead to structural failure from flutter, control surface overload, or airframe deformation.

Key Terms

Source

Q89: In a glider cockpit, three handles are colored red, blue, and green. Which controls do they correspond to? ^t20q89

DE · FR

Answer

C)

Explanation

The standard EASA color convention for glider cockpit handles is: red for the emergency canopy release, blue for the airbrakes (speed brakes/spoilers), and green for the trim. This consistent color coding ensures pilots can identify critical controls quickly and correctly under stress. - A incorrectly assigns red to airbrakes. - B incorrectly assigns red to the undercarriage. - D incorrectly assigns red to airbrakes and green to undercarriage. Only C correctly maps all three colors to their respective controls.

Key Terms

EASA = European Union Aviation Safety Agency

Source

Q90: For a glider with an empty weight of 275 kg, determine the correct combination of maximum payload and permitted water ballast. ^t20q90

DE · FR

![](figures/t20_q90.png)

Answer

D)

Explanation

The question asks for the maximum payload (heaviest cockpit load) with its permitted water ballast. To find this, plot each answer on the loading chart at y=275 kg empty weight:

  1. Find 275 kg on the Y-axis (left = empty weight). Draw a horizontal line to the right.

  2. For each answer, check the cockpit load on the X-axis and whether the point is in the white (allowed) zone or the hatched (forbidden) zone.

  3. A (85 kg + 100L): at x=85, the point is in the white zone. Valid, but 85 kg is not the maximum payload.

  4. B (100 kg + 80L): at x=100, the point is in the white zone. Valid, but 100 kg is not the maximum payload either.
  5. C (110 kg + 65L): at x=110, the point is in the hatched forbidden zone. Not permitted.
  6. D (105 kg + 70L): at x=105, the point is right at the boundary of the hatched zone, on the 70L diagonal. This is the maximum cockpit load (105 kg) that's still permitted, with 70L water ballast.

Answer D gives the maximum payload (105 kg) with the corresponding permitted water ballast (70L) — exactly at the limit of the loading envelope.

Ref: Astir CS 77 Flight Manual, p.5

Source

Q91: To which loading category of a glider does the parachute belong? ^t20q91

DE · FR

Answer

C)

Explanation

The correct answer is C because the parachute is carried by the pilot and is not a permanent part of the aircraft structure, so it falls under useful load (payload).

Source

Q92: If the static pressure port is blocked, which instruments will malfunction? ^t20q92

DE · FR

Answer

C)

Explanation

The correct answer is C because the altimeter, variometer, and airspeed indicator all rely on static pressure to function. The altimeter measures static pressure directly to determine altitude, the variometer detects changes in static pressure over time, and the airspeed indicator compares pitot (total) pressure against static pressure.

Source

Q93: What is the function of a weak link (Sollbruchstelle) in a glider tow rope? ^t20q93

DE · FR

Answer

B)

Explanation

A weak link is a calibrated breaking element installed in the tow rope. Its purpose is to fail at a predetermined tensile load that is below the structural limit of either the glider or the tow aircraft (or winch system). When the load on the rope exceeds that limit — for example because of a sudden manoeuvre, a winch that pulls too hard, or an abnormal climb angle — the weak link parts before the airframe is overstressed.

Source

DE · FR

Answer

D)

Explanation

The correct answer is D because the Tost safety hook is designed with a mechanical release mechanism that triggers automatically when the cable angle exceeds approximately 70 degrees relative to the longitudinal axis, protecting the glider from a dangerous nose-down pitch (winch launch upset).

Source

Q95: What does an accelerometer in a glider measure? ^t20q95

DE · FR

Answer

B)

Explanation

The correct answer is B because a glider's accelerometer (g-meter) measures the load factor along the aircraft's vertical axis in the plane of symmetry, which is perpendicular to the roll (longitudinal) axis. This captures the combined effect of gravitational and manoeuvre-induced accelerations.

Source

Q96: For a glider with 255 kg empty weight and a pilot weighing 100 kg equipped, what is the maximum water ballast allowed? See attached sheet. ^t20q96

DE · FR

![](figures/t20_q90.png)

Answer

B)

Explanation

The correct answer is B because the calculation is: empty weight (255 kg) + pilot (100 kg) = 355 kg. If the maximum all-up mass is 450 kg, then the remaining capacity for water ballast is 450 - 355 = 95 kg, which equals approximately 95 litres (since water density is 1 kg/L).

Source

Q97: What must be especially considered when installing an oxygen system? ^t20q97

DE · FR

Answer

C)

Explanation

The correct answer is C because the primary safety requirement for any oxygen system is that the pilot can operate it and read its indicators (flow rate, bottle pressure) during flight without difficulty. If the system cannot be monitored in flight, the pilot has no way to detect a malfunction or depletion.

Source

DE · FR

Answer

C)

Explanation

The correct answer is C because an on-demand regulator performs two functions: it enriches the air/oxygen mixture progressively as altitude increases (to compensate for decreasing partial pressure of oxygen), and it delivers gas only during inhalation, conserving the limited oxygen supply.

Source

Q99: What is the operating principle of diaphragm and vane variometers? ^t20q99

DE · FR

Answer

C)

Explanation

The correct answer is C because both diaphragm and vane variometers work by comparing the atmospheric static pressure (which changes with altitude) against the pressure inside a sealed reference vessel connected to the atmosphere through a calibrated restriction. When the aircraft climbs or descends, a pressure differential develops across the restriction, deflecting a diaphragm or vane to indicate the rate of altitude change.

Source

Q100: What does the red mark on a glider's airspeed indicator indicate? ^t20q100

DE · FR

Answer

D)

Explanation

The correct answer is D because the red radial line on a glider's airspeed indicator marks VNE (velocity never exceed), the maximum speed at which the aircraft may be operated under any conditions. Exceeding VNE risks structural failure due to aerodynamic loads or flutter.

Key Terms

Source

Q101: How can you determine whether a glider is approved for aerobatics? ^t20q101

DE · FR

Answer

B)

Explanation

The correct answer is B because the aircraft flight manual (AFM) is the authoritative document that specifies the approved operating categories, including whether aerobatic flight is permitted, and under what conditions and limitations.

Source

Q102: Where can you find data on the limits, loading, and operation of a glider? ^t20q102

DE · FR

Answer

C)

Explanation

The correct answer is C because the aircraft flight manual (AFM) is the official regulatory document that contains all operating limitations, loading data (mass and balance), performance charts, and operational procedures for a specific aircraft type.

Source

Q103: Which instruments are depicted in the diagram below? ^t20q103

DE · FR

![](figures/t20_q103.png)

Answer

C)

Explanation

The correct answer is C because the diagram shows, from left to right, the airspeed indicator (ASI), altimeter, and a vane variometer — the standard "basic T" arrangement in a glider cockpit. A and B incorrectly identify the order of the ASI and altimeter and misidentify the variometer type.

Source

Q104: What speed range does the white arc on a glider's airspeed indicator represent? ^t20q104

DE · FR

Answer

D)

Explanation

The correct answer is D because on a glider's ASI, the white arc indicates the speed range within which camber flaps (positive flap settings) may be deployed. Operating flaps outside this range risks structural damage or adverse handling characteristics.

Key Terms

Source

Q105: The airspeed indicator on a glider is defective. Under what condition may the glider fly again? ^t20q105

DE · FR

Answer

C)

Explanation

The correct answer is C because the airspeed indicator is a mandatory minimum instrument required for flight. The glider may only return to service once the ASI has been repaired or replaced and is fully functional.

Source

DE · FR

Answer

D)

Explanation

The correct answer is D because when the minimum useful load (typically minimum cockpit load) is not met, the C.G. may be outside the aft limit and the wing loading may be below the certified minimum. Adding lead ballast at the prescribed location (usually forward) brings the total load up to the minimum required value and positions the C.G. within limits.

Key Terms

CG = Centre of Gravity

Source

DE · FR

Answer

C)

Explanation

The correct answer is C because the maximum mass is a hard certification limit based on structural strength and stall speed. When it is exceeded, the aircraft is no longer within its certified flight envelope and flight is prohibited until the excess load is removed.

Source

Q108: How is the centre of gravity of a single-seat glider shifted? ^t20q108

DE · FR

Answer

C)

Explanation

The correct answer is C because in a single-seat glider, the only practical way to move the C.G. is by changing the mass in the cockpit — adding or removing lead ballast at forward or aft positions, or by a different pilot weight.

Source

Q109: Which centre of gravity position on a glider is the most hazardous? ^t20q109

DE · FR

Answer

D)

Explanation

The correct answer is D because an aft C.G. beyond the rear limit reduces the longitudinal static stability of the glider. As the C.G. moves closer to or behind the neutral point, the aircraft becomes neutrally stable or unstable in pitch, making it progressively harder to control until recovery from any pitch disturbance becomes impossible.

Source

Q110: What speed range does the yellow arc on a glider's airspeed indicator represent? ^t20q110

DE · FR

Answer

D)

Explanation

The correct answer is D because the yellow arc on a glider's ASI marks the caution range between VNO (maximum structural cruising speed) and VNE (never-exceed speed). Flight within this speed range is permitted only in smooth, non-turbulent air because turbulence-induced loads at these speeds could exceed the structural design limits.

Key Terms

Source

Q111: What causes the dip error on a direct-reading compass? ^t20q111

DE · FR

Answer

B)

Explanation

The correct answer is B because the Earth's magnetic field lines are not horizontal — they dip downward toward the magnetic poles at an angle that increases with latitude. This inclination causes the compass magnet assembly to tilt, introducing errors during turns (northerly turning error) and during accelerations/decelerations.

Source

DE · FR

Answer

C)

Explanation

The correct answer is C because yellow marks the caution range on an airspeed indicator, spanning from VNO to VNE. This range is reserved for smooth-air flight only. The colour coding is standardised across aviation to ensure immediate recognition.

Key Terms

Source

Q113: If the altimeter subscale setting is changed from 1000 hPa to 1010 hPa, what difference in altitude is displayed? ^t20q113

DE · FR

Answer

C)

Explanation

The correct answer is C because in the International Standard Atmosphere, 1 hPa corresponds to approximately 8 metres of altitude near sea level (the "30 ft per hPa" rule). Increasing the subscale setting by 10 hPa (from 1000 to 1010) raises the displayed altitude by approximately 10 x 8 = 80 metres.

Key Terms

Source

DE · FR

Answer

C)

Explanation

The correct answer is C because QFE is the atmospheric pressure measured at the aerodrome reference point. When this value is set on the altimeter subscale, the instrument reads zero on the ground at that aerodrome and indicates height above the aerodrome during flight.

Key Terms

Source

DE · FR

Answer

C)

Explanation

The correct answer is C because if the compensating (equalising) tank is oversized, it stores more pressure than intended, creating a larger pressure differential across the variometer restriction when altitude changes. This amplifies the indicated vertical speed, producing a reading that is too high (over-indication).

Source

DE · FR

Answer

B)

Explanation

The correct answer is B because a variometer (vertical speed indicator) compares the current atmospheric static pressure with the pressure retained in a reference chamber connected through a calibrated leak. As altitude changes, the instantaneous static pressure diverges from the stored (previous) pressure, and this differential drives the indication.

Source

Q117: What type of engine is typically used in Touring Motor Gliders (TMG)? ^t20q117

DE · FR

Answer

C)

Explanation

The correct answer is C because Touring Motor Gliders (TMGs) are typically powered by four-cylinder, four-stroke piston engines such as the Rotax 912 or Limbach series, which offer a good balance of reliability, power-to-weight ratio, and fuel economy for sustained powered flight.

Key Terms

Source

DE · FR

Answer

D)

Explanation

The correct answer is D because the yellow arc on the ASI indicates the caution speed range (VNO to VNE), within which flight is only permitted in smooth air without gusts. At these higher speeds, turbulence-induced load factors could exceed structural design limits.

Key Terms

Source

DE · FR

Answer

C)

Explanation

The correct answer is C because a total-energy compensated variometer eliminates the effect of speed changes (kinetic energy exchanges) on the vertical speed indication. In a steady glide with constant airspeed, the TE variometer indicates the vertical movement of the surrounding air mass — showing zero in still air, or the actual thermal/sink value in moving air.

Source

DE · FR

Answer

D)

Explanation

The correct answer is D because during a right turn, a yaw string deflecting to the left indicates the nose is sliding outward (skidding turn) — there is insufficient rudder coordination and possibly too much bank for the rate of turn. To correct this, apply more right rudder (in the direction of the turn) to bring the nose around, and reduce bank slightly to decrease the tendency to skid. A and C are wrong because they call for less rudder, which would worsen the skid.

Source

DE · FR

Answer

C)

Explanation

Airworthiness of an aircraft is fundamentally determined by the structural integrity of load-bearing components (main spar, wing attachment, fuselage frames, control system attachment points). Damage to these parts compromises the aircraft's ability to sustain flight loads and constitutes a loss of airworthiness.

Source

DE · FR

Answer

C)

Explanation

The load sheet (weight and balance document) specifies a minimum pilot weight to ensure the centre of gravity remains within approved limits. If the actual pilot weight is below the minimum, ballast must be added (typically in the ballast area specified by the POH) to bring the total loaded mass up to the minimum required value.

Key Terms

CG = Centre of Gravity

Source

DE · FR

Answer

A)

Explanation

Minimum speed (stall speed) is proportional to the square root of wing loading: Vs ∝ √(W/S). If wing loading increases by 40% (factor 1.4), stall speed increases by √1.4 ≈ 1.183, i.e., approximately 18.3%. Only the square-root relationship gives approximately 18%.

Key Terms

Source

Q124: The maximum load according to the load sheet has been exceeded. What action must be taken? ^t20q124

DE · FR

Answer

C)

Explanation

If the actual loaded mass exceeds the maximum allowed mass from the load sheet, the only correct action is to reduce the load (remove ballast, water ballast, baggage, or have a lighter pilot). Exceeding maximum mass means structural load limits may be reached at lower G-loads or airspeeds.

Source

DE · FR

Answer

A)

Explanation

A torsion-stiffened leading edge is a structural design feature in which the leading edge of the wing (from the leading edge to the main spar) is planked (covered) on both upper and lower surfaces, creating a closed-section D-box that resists torsional (twisting) loads.

Source

DE · FR

Answer

B)

Explanation

Maximum permissible airspeeds (VNE, VNO, etc.) are published in the Pilot's Operating Handbook (POH/AFM), displayed on the cockpit instrument panel (placard), and indicated on the airspeed indicator by the red line (VNE) and arc markings.

Key Terms

Source

DE · FR

Answer

A)

Explanation

The airspeed indicator is a required instrument for safe flight; without it a pilot cannot determine safe operating speeds, stall speed, or structural speed limits. An inoperative airspeed indicator means the aircraft must remain on the ground until the instrument is serviceable.

Key Terms

IAS = Indicated Airspeed

Source

DE · FR

Answer

A)

Explanation

During a left turn, a yaw string deflecting to the left indicates the aircraft is slipping into the turn (too much bank relative to rudder input). To centre the string in a slip, the pilot needs to increase bank to steepen the turn and reduce rudder (less rudder in the turn direction). This is opposite to correcting a skid.

Source

DE · FR

Answer

C)

Explanation

Winglets are upward (or downward) curving extensions at the wingtip that reduce induced drag by weakening the wingtip vortex — the main source of induced drag on a finite wing.

Source

DE · FR

Answer

C)

Explanation

Dynamic pressure (q) is defined by Bernoulli's equation as q = ½ρv², where ρ is air density and v is airflow speed. Dynamic pressure depends directly on air density and the square of velocity.

Key Terms

Source

Q131: The airspeed indicator, altimeter and vertical speed indicator all display incorrect readings simultaneously. What could be the cause? ^t20q131

DE · FR

Answer

C)

Explanation

The airspeed indicator, altimeter, and vertical speed indicator are all connected to the static pressure port. If the static pressure system is blocked (e.g., by ice, water, or a cover left on), all three instruments will give erroneous readings simultaneously.

Source

DE · FR

Answer

B)

Explanation

The altimeter's reference pressure (subscale) must be set before every flight to the correct local QNH/QFE so that the altimeter reads the correct altitude or height. During cross-country flights, QNH changes as the pilot moves between pressure regions, so updates are required when crossing into new altimeter setting regions.

Key Terms

Source

DE · FR

Answer

D)

Explanation

Magnetic inclination (dip) is the angle between the Earth's magnetic field vector and the horizontal plane at any given location. It is 0° at the magnetic equator and 90° at the magnetic poles. - Deviation (A) is the error caused by magnetic fields within the aircraft. - Magnetic variation/declination (B) is the angle between magnetic and true north.

Key Terms

D — Drag

Source

Q134: As air density decreases, the airflow speed at stall increases (TAS) and vice versa. How should a final approach be flown on a hot summer day? ^t20q134

DE · FR

Answer

D)

Explanation

The airspeed indicator measures IAS (Indicated Airspeed), which is derived from dynamic pressure. At lower air density (hot day, high altitude), TAS is higher than IAS for the same dynamic pressure. The aerodynamic behaviour of the wing (lift, stall) depends on dynamic pressure (and thus IAS), not on TAS. Therefore stall occurs at the same IAS regardless of density.

Key Terms

Source

DE · FR

Answer

D)

Explanation

The load factor (n) is the ratio of the aerodynamic lift acting on the aircraft to the aircraft's weight: n = L/W. In level unaccelerated flight, n = 1. In turns or pull-ups, n increases.

Key Terms

Source

Q136: The term static pressure is defined as the pressure ^t20q136

DE · FR

Answer

D)

Explanation

Static pressure is the pressure of the undisturbed ambient airmass — the atmospheric pressure acting equally in all directions at a given altitude. It is sensed through flush static ports on the fuselage skin.

Source

Q137: The term inclination is defined as ^t20q137

DE · FR

Answer

C)

Explanation

Magnetic inclination (dip) is the angle between the Earth's total magnetic field vector and the local horizontal plane. - At the magnetic equator, field lines are horizontal (0° dip); at the poles, they are vertical (90° dip). Deviation (A) is caused by onboard magnetic interference. - Variation/declination (B) is the angle between magnetic and geographic north.

Key Terms

D — Drag

Source

Q138: How does the maximum permitted speed VNE of a glider change as altitude increases? ^t20q138

DE · FR

Answer

C)

Explanation

VNE (never-exceed speed) is specified as an indicated airspeed (IAS) in the flight manual, but the structural limit is actually a true airspeed (TAS). At higher altitudes, air density decreases: for the same IAS, TAS is higher, increasing aerodynamic loads and flutter risk. Therefore the published IAS-based VNE decreases with altitude to maintain structural safety margins. A (unchanged) is incorrect. B (increases) is incorrect. D (depends on temperature) is partially true but not the expected exam answer.

Key Terms

Source

Q139: What happens inside a Venturi nozzle? ^t20q139

DE · FR

Answer

B)

Explanation

According to Bernoulli's principle, in a Venturi nozzle the narrowing cross-section accelerates the airflow. This increase in velocity is accompanied by a decrease in static pressure, creating a depression (pressure below ambient). This principle is used in various aircraft instruments and systems. A (overpressure) is the opposite of what occurs. C (heating) does not occur significantly. D (constant dynamic pressure) is incorrect as dynamic pressure changes with velocity.

Key Terms

Source

Q140: How often is a glider inspected by the aeronautical authority (OFAC in Switzerland)? ^t20q140

DE · FR

Answer

B)

Explanation

In Switzerland, OFAC (Federal Office of Civil Aviation) requires a periodic airworthiness review of gliders every 3 years (Nachprufung / airworthiness review). This review confirms the aircraft remains compliant with its type certification basis and that all applicable airworthiness directives have been complied with. A (annually) is too frequent for the official OFAC review. C and D (only after damage or ownership change) are insufficient as standalone triggers.

Key Terms

Source

Q141: How does true airspeed (TAS) change as a glider climbs at constant indicated airspeed (IAS)? ^t20q141

DE · FR

Answer

A)

Explanation

The airspeed indicator measures dynamic pressure (q = 1/2 x rho x V2). At higher altitude, air density (rho) is lower. To maintain the same dynamic pressure (constant IAS), true airspeed (TAS) must therefore be higher. As a rule of thumb, TAS increases by approximately 2% per 300 m (1,000 ft) of altitude at constant IAS. B (decreases) and C (stays the same) are incorrect. D is incorrect because air density varies with altitude and directly affects the IAS/TAS relationship.

Key Terms

Source

Q142: What does the term "empty mass" of a glider mean? ^t20q142

DE · FR

Answer

B)

Explanation

The empty mass (Leermasse / basic empty weight) of a glider is the mass of the fully constructed glider including all installed instruments, fixed equipment (radio, ELT, fixed oxygen system, etc.) and non-usable fluids. It excludes variable useful loads such as the pilot, parachute, water ballast, and baggage. A (barograph, battery, parachute) mixes fixed equipment with payload. C (ballast and tools) is not part of empty mass. D (baggage, water ballast and occupants) constitutes the useful load.

Key Terms

Source

Q143: Which of the following items is NOT considered part of the "useful load" (payload) of a glider? ^t20q143

DE · FR

Answer

D)

Explanation

A fixed (permanently installed) oxygen system is part of the aircraft's fixed equipment and is therefore included in the empty mass, not in the variable useful load. The useful load comprises only variable items that can be added or removed between flights: pilot and passenger (A), parachute (B), portable instruments such as a portable barograph (C). A fixed installation, whether in use or not, remains permanently in the aircraft and is counted in the empty mass.

Key Terms

Source