### Q51: Which glider cockpit lever is painted red? ^t20q51 - A) Wheel brake. - B) Landing gear lever. - C) Ventilation control. - D) Emergency canopy release. **Correct: 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 landing gear lever (B) uses green. Ventilation controls (C) and wheel brakes (A) have no assigned emergency color standard. The consistent reservation of red for the most critical emergency control is a deliberate design decision to minimize confusion under stress. Only D is correct. --- ### Q52: During winter maintenance, you notice honeycomb elements inside the fuselage. What construction category does this glider belong to? ^t20q52 - A) Metal construction. - B) Wood combined with other materials. - C) Composite construction. - D) Biplane construction. **Correct: 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. Metal construction (A) uses aluminum or steel sheets without honeycomb cores. Wood/mixed construction (B) uses spruce ribs and plywood skins. Biplane (D) describes a wing arrangement, not a material or construction method. The presence of honeycomb elements unambiguously identifies C. --- ### Q53: The Discus B has its horizontal stabilizer mounted at the top of the fin. What type of tail configuration is this? ^t20q53 - A) V-tail. - B) Cruciform tail. - C) T-tail. - D) Pendulum cruciform tail. **Correct: 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. A (V-tail) merges horizontal and vertical tail functions into two angled surfaces. B (cruciform tail) positions the stabilizer at mid-height of the fin. D (pendulum cruciform) is a variant with an all-moving stabilizer at mid-height. Only C is correct. --- ### Q54: What is the role of the fixed vertical fin and fixed horizontal stabilizer on a glider's tail? ^t20q54 - A) To trim the glider. - B) To steer the glider. - C) To stabilize the glider. - D) To trim the control forces for a desired flight condition. **Correct: 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. B (steering) is accomplished by the movable surfaces: elevator for pitch, rudder for yaw, ailerons for roll. A and D (trimming) is the function of trim tabs mounted on the movable surfaces, not the fixed stabilizers. Only C correctly identifies the role of the fixed tail surfaces. --- ### Q55: During winter maintenance, the equipment officer explains the CG-mounted tow hook mechanism. Why must it release the cable automatically? ^t20q55 - A) To relieve the pilot from releasing the cable during a winch launch. - B) To prevent danger if the glider flies too long near the ground during the winch launch takeoff roll. - C) To prevent danger when the glider climbs too high during aero-tow. - D) It is a safety measure — the hook must release automatically when the glider risks flying over the winch. **Correct: 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. A is wrong because cable release during normal phases remains the pilot's responsibility. B describes a different ground-handling concern. C refers to an aero-tow scenario where the CG hook is not used. Only D correctly identifies the primary safety rationale. --- ### Q56: Aileron deflection produces rotation around which axis? ^t20q56 - A) The yaw axis. - B) The lateral axis. - C) The vertical axis. - D) The longitudinal axis. **Correct: 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. B (lateral axis, running wingtip to wingtip) corresponds to pitch, controlled by the elevator. A (yaw axis) and C (vertical axis) describe the same axis, controlled by the rudder; note that adverse yaw is a secondary effect of aileron use, not the primary motion. Only D is correct. --- ### Q57: When the control stick is moved to the left, what happens? ^t20q57 - A) Both ailerons move upward. - B) The left aileron goes up and the right aileron goes down. - C) Both ailerons move downward. - D) The left aileron goes down and the right aileron goes up. **Correct: 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. --- ### Q58: In mechanical brake systems, how is the braking force transmitted from the pedals or handles to the brake shoes? ^t20q58 - A) Through electric motors. - B) Through hydraulic lines. - C) Through pneumatic lines. - D) Through cables and pushrods. **Correct: 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. Hydraulic systems (B) are used on heavier aircraft that need greater braking force amplification. Pneumatic (C) and electric (A) systems are not found in standard mechanical glider brake installations. Only D is correct. --- ### Q59: The flight manual states that the glider has balanced control surfaces. What is the main reason for this design? ^t20q59 - A) Better turning characteristics. - B) Harmonious coordination of controls. - C) Elimination of flutter. - D) Reduction of the force needed to move the controls. **Correct: 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. D (lighter controls) may result from aerodynamic balancing but is not the purpose of mass balancing. A and B describe general handling qualities unrelated to structural safety. Only C is correct. --- ### Q60: Why are there small holes on the fuselage sides connected to internal flexible tubes? ^t20q60 - A) They serve as static pressure ports for the instruments. - B) They are used to measure outside air temperature. - C) They equalize pressure between the fuselage interior and exterior. - D) They prevent excess humidity inside the glider in cold weather. **Correct: 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. B (outside air temperature) uses a dedicated thermometer probe. C and D describe ventilation or moisture-control functions, which are unrelated to these ports. Only A is correct. ### Q61: Which instrument receives its input from the Pitot tube? ^t20q61 - A) Turn indicator. - B) Variometer. - C) Altimeter. - D) Airspeed indicator. **Correct: 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. A (turn indicator) is a gyroscopic instrument powered pneumatically or electrically. B (variometer) and C (altimeter) are both connected only to the static port, measuring changes in ambient atmospheric pressure. ### Q62: If the altimeter subscale is set to a higher pressure without any actual pressure change, how does the reading change? ^t20q62 - A) The reading increases. - B) The reading decreases. - C) A precise answer requires knowing the outside air temperature. - D) The reading does not change. **Correct: 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. B, C, and D are all incorrect. Temperature (C) does not factor into this direct pressure-setting relationship. The reading always increases when a higher pressure is dialed in. ### Q63: If the static pressure port is blocked by ice during a descent, what does the variometer show? ^t20q63 - A) A descent. - B) A climb. - C) Zero. - D) Nothing at all (only a warning flag appears). **Correct: 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. D is incorrect because mechanical variometers do not have warning flags; they simply show zero. ### Q64: The red line on the airspeed indicator marks VNE. Is exceeding this speed ever permitted? ^t20q64 - A) Yes, brief exceedances are acceptable. - B) Yes, up to a maximum of 20%. - C) No, under no circumstances. - D) Yes, up to a maximum of 10%. **Correct: 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. A, B, and D all incorrectly suggest that some degree of exceedance is acceptable, which is false and dangerous. ### Q65: Switching on the radio in a glider consistently causes the magnetic compass to rotate in the same direction. Why? ^t20q65 - A) The compass is powered electrically when the radio is activated. - B) The compass is running low on fluid. - C) The compass is defective. - D) The radio's magnetic field interferes with the compass because the two are installed too close together. **Correct: 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. A is wrong because compasses are self-contained magnetic instruments. B (low fluid) would cause sluggish movement, not directional bias. C (defective compass) is not the root cause here. ### Q66: What information does FLARM provide? ^t20q66 - A) Only FLARM-equipped aircraft that are at the same altitude. - B) Only FLARM-equipped aircraft that cross the flight path. - C) FLARM-equipped aircraft in the vicinity as well as fixed obstacles. - D) Only FLARM-equipped aircraft posing a collision risk. **Correct: 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. A is too restrictive (not limited to same altitude). B is too restrictive (not limited to path-crossing traffic). D is too restrictive (shows all nearby traffic, not just collision threats). ### 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 - A) OFF. - B) ON. - C) ARM. - D) Automatic activation is independent of the selected mode for safety reasons. **Correct: 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. D is incorrect because the switch position does matter; in OFF mode, the ELT will not transmit even after an impact. ### Q68: Electric current is measured in which unit? ^t20q68 - A) Watt. - B) Volt. - C) Ohm. - D) Ampere. **Correct: D)** > **Explanation:** Electric current is measured in Amperes (A), named after physicist Andre-Marie Ampere. Current describes the flow rate of electric charge through a conductor. A (Watt) is the unit of electrical power (P = U x I). B (Volt) is the unit of voltage or electrical potential difference. C (Ohm) is the unit of electrical resistance. 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. ### 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 - A) Yes, but only if a short local flight near the aerodrome is planned. - B) Yes, provided the instruments start working again. - C) No, an unrated fuse substitute risks wiring fire or instrument damage. - D) Yes, but only in an emergency situation. **Correct: 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. A, B, and D all incorrectly suggest scenarios where this improvisation might be acceptable. The aircraft must not fly until a proper fuse is installed. ### Q70: What is the primary disadvantage of the VHF frequency band used in aviation radio communications? ^t20q70 - A) VHF waves are highly susceptible to atmospheric disturbances such as thunderstorms. - B) VHF reception is limited to the theoretical line of sight (quasi-optical propagation). - C) VHF waves are deflected at dawn and dusk due to the twilight effect. - D) VHF waves are disrupted near large bodies of water (coastal effect). **Correct: 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. A (atmospheric disturbances) primarily affects MF/HF frequencies. C (twilight effect) is a phenomenon of ionospheric HF propagation. D (coastal effect) affects medium-frequency (MF) waves, not VHF. ### Q71: Which instrument is connected to the Pitot tube? ^t20q71 - A) Altimeter. - B) Turn indicator. - C) Airspeed indicator. - D) Variometer. **Correct: 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. A (altimeter) and D (variometer) are connected only to the static port. B (turn indicator) is a gyroscopic instrument that operates either pneumatically or electrically and has no connection to the Pitot-static system. ### Q72: What is the standard colour of aviation oxygen cylinders? ^t20q72 - A) Red. - B) Orange. - C) Black. - D) Blue/white. **Correct: C)** > **Explanation:** Under European and ISO standards, aviation oxygen cylinders are conventionally painted black. This distinguishes them from other gas types in the color coding system. Medical oxygen bottles may be white, but aviation oxygen specifically uses black as the standard identification color. A (red) typically indicates flammable gases like hydrogen or acetylene. B (orange) and D (blue/white) do not correspond to the standard aviation oxygen bottle color coding. ### Q73: During a turn, what does the ball (inclinometer) indicate? ^t20q73 - A) The bank angle of the glider. - B) A rotation about the yaw axis to left or right. - C) The lateral acceleration in a turn. - D) The resultant of weight and centrifugal force. **Correct: 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). A is wrong because the ball does not measure bank angle directly. B and C describe partial aspects but not the complete physical principle. ### Q74: Why must the equipped weight of a glider pilot exceed a specified minimum value? ^t20q74 - A) To improve the angle of incidence. - B) To reduce control forces. - C) To keep the centre of gravity within prescribed limits. - D) To improve the glide ratio. **Correct: 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. A (angle of incidence) is a fixed design parameter that pilot weight does not affect. B (control forces) are not the primary reason for the minimum weight. D (glide ratio) is primarily determined by aerodynamic design, not pilot weight. ### Q75: What is the purpose of a glider's flight manual (AFM)? ^t20q75 - A) It contains records of periodic inspections and repairs performed. - B) It is a detailed commercial brochure from the manufacturer. - C) It is used by workshop supervisors when carrying out repairs. - D) It provides the pilot with operating limits, technical specifications, and emergency procedures. **Correct: 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. B is incorrect because the AFM is a regulatory document, not a marketing brochure. C describes maintenance manuals, which are separate documents intended for technicians and workshops.