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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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).
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.
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.
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.
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.
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.
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.
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.
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.
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.