Correct: 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. Option A incorrectly assigns red to speed brakes and blue to the canopy lock. Option C incorrectly assigns red to landing gear. Option D incorrectly assigns red to speed brakes and blue to cable release.
Correct: 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. Option A (outermost section) would measure near the wingtip where the profile is thinnest. Option B (thinnest cross-section) gives a minimal, less useful value. Option C (innermost/root) describes a spanwise location, not the airfoil thickness definition.
Correct: 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. Option A (monocoque) is the opposite -- the skin carries all loads with no internal framework. Option B (semi-monocoque) uses both a frame and a load-bearing skin working together. Option D (honeycomb structure) is a core material used in sandwich panels, not a fuselage construction type.
Correct: 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. Option A introduces "girders" which is non-standard fuselage terminology. Option B includes "ribs" which are wing components, not fuselage. Option D lists "covers" and "forming parts" which are not primary structural terms.
Correct: 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. Option A (grid construction) has a non-load-bearing skin. Option B (honeycomb) is a material type, not a structural concept. Option C (wood/mixed) is a material classification, not a structural design.
Correct: 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). Option A incorrectly includes ailerons, which are wing-mounted. Option C also incorrectly includes ailerons. Option D lists cockpit controls, not aircraft structure.
Correct: 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. Options A and C specify a heavy core, which defeats the weight-saving purpose. Options B and C specify thick layers, which add unnecessary mass.
Correct: 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. Option A (spar) is the main spanwise load-bearing beam but does not define the profile shape. Option B (planking/skin) covers the structure but follows the shape determined by the ribs. Option D (wingtip) is the outer end of the wing, not a profile-shaping element.
Correct: 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. Options A, C, and D describe unrelated force ratios.
Correct: 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. Options A and C emphasise temperature resistance, which is not a primary advantage since most cores are temperature-sensitive. Option D focuses on formability, which is actually limited in sandwich construction.
Correct: 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. Option B (aluminium) is strong but significantly weaker than CFRP. Option D (magnesium) is lighter than aluminium but lower in absolute strength. Option A (wood) has good specific strength but is the weakest in absolute terms among those listed.
Correct: 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. Option A (adverse yaw) is addressed by rudder coordination, not trim. Options B and D refer to rudder and aileron forces, which are not adjusted by the standard glider trim lever.
Correct: 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. Option A (stall) is an aerodynamic event that does not damage structure. Option B (low airspeed) reduces loads. Option D (neutralising stick forces) does not create structural loads.
Correct: 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). Option B uses mathematical labels but omits aviation-specific names. Options A and D fabricate a non-existent fourth axis.
Correct: D)
Explanation: Ailerons control roll -- rotation around the longitudinal axis. When one aileron deflects up and the other down, differential lift rolls the aircraft. Option A (rudder) controls yaw around the vertical axis. Option C (elevator) controls pitch around the lateral axis. Option B (trim tab) modifies control forces but is not a primary roll initiator.
Correct: 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. Option A (fly-by-wire) is used on modern airliners and military aircraft. Options B and D (hydraulic systems) are used on larger aircraft requiring greater control forces.
Correct: 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. Options B and D have incorrect yaw direction. Option C has correct yaw but incorrect secondary roll direction.
Correct: 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. Option B incorrectly states the tail force is upward. Option C describes a forward stick input. Option D has the correct force but wrong nose direction.
Correct: 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. Option A lists secondary/high-lift devices only. Option B is too vague and includes secondary controls. Option D mixes primary with secondary controls (trim tabs, high-lift devices, power controls).
Correct: 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. Option A is incorrect -- they are not backup systems. Option B describes primary controls. Option D is too narrow, covering only one aspect of flap function.
Correct: 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. Options A and C have the tab moving up (nose-down trim). Option B has both moving down, which is mechanically impossible in a normal trim system.
Correct: 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. Option A (CG position) affects how much trim is needed but not the direction. Option B (upward) would produce nose-down trim. Option C (rudder direction) is unrelated to elevator trim operation.
Correct: 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. Option A (lock surfaces) is incorrect -- trim holds an aerodynamic equilibrium, not a mechanical lock. Option B (shift CG) is wrong -- only physically moving mass changes CG. Option D (adverse yaw) is a roll-yaw coupling unrelated to trim.
Correct: 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. Option A describes a consequence, not the purpose. Option B (static electricity) is an unrelated electrical phenomenon. Option C (ice prevention) is handled by optional Pitot heating, not the system's design purpose.
Correct: 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). Option A (static pressure) is measured by separate static ports. Option C (cabin pressure) is unrelated. Option D (dynamic pressure) is not measured directly by the Pitot tube -- it is derived by subtracting static from total pressure inside the ASI.
