[ { "ch": "What instrument is measured atmospheric pressure?", "ansGr": [ { "ans": [ "Barometer", "true" ] }, { "ans": [ "Thermometer", "false" ] }, { "ans": [ "Hygrometer", "false" ] } ] }, { "ch": "In which layer of atmosphere does most civilian aviation take place?", "ansGr": [ { "ans": [ "Troposphere", "true" ] }, { "ans": [ "Mesosphere", "false" ] }, { "ans": [ "Thermosphere", "false" ] } ] }, { "ch": "What is absolute humidity?", "ansGr": [ { "ans": [ "The actual amount of the water vapour in a mixture of air and water", "true" ] }, { "ans": [ "The temperature to which humid air must be cooled at constant pressure to become saturated.", "false" ] }, { "ans": [ "The ratio of the water vapour actually present in the atmosphere to the amount that would be present if the air were saturated at the prevailing temperature and pressure", "false" ] } ] }, { "ch": "What happens to the density of air as altitude is increased ?", "ansGr": [ { "ans": [ "Decreases.", "true" ] }, { "ans": [ "Stays the same", "false" ] }, { "ans": [ "Increases.", "false" ] } ] }, { "ch": "What is the temperature in comparison to ISA conditions at 30,000ft ?", "ansGr": [ { "ans": [ "-44.4°C", "true" ] }, { "ans": [ "0°C", "false" ] }, { "ans": [ "-60°C", "false" ] } ] }, { "ch": "Which is layer between troposphere and stratosphere ?", "ansGr": [ { "ans": [ "Tropopause", "true" ] }, { "ans": [ "Thermosphere", "false" ] }, { "ans": [ "Mesosphere", "false" ] } ] }, { "ch": "Which has the greater density?", "ansGr": [ { "ans": [ "Air at low altitude", "true" ] }, { "ans": [ "Air at high altitude", "false" ] }, { "ans": [ "It remains constant", "false" ] } ] }, { "ch": "How is pressure as altitude increases ?", "ansGr": [ { "ans": [ "Decreases exponentially", "true" ] }, { "ans": [ "Decreases at constant rate.", "false" ] }, { "ans": [ "Increases exponentially", "false" ] } ] }, { "ch": "What layer has the ozone layer in it?", "ansGr": [ { "ans": [ "Stratosphere", "true" ] }, { "ans": [ "Troposphere", "false" ] }, { "ans": [ "Mesosphere", "false" ] } ] }, { "ch": "Why does an aircraft require a longer runway for take off on damp days than it does on dry days ?", "ansGr": [ { "ans": [ "On damp days, the air density is less than on dry days", "true" ] }, { "ans": [ "On damp days, the air density is more than on dry days", "false" ] }, { "ans": [ "On damp days, the air density is same on dry days", "false" ] } ] }, { "ch": "Which aircraft will fly for a longer distance, one aircraft flies at 1,000 ft and another aircraft flies at 10,000 ft , both aircraft have identical throttle settings (and engine thrust) ?", "ansGr": [ { "ans": [ "The aircraft flying at 10 000 ft", "true" ] }, { "ans": [ "The aircraft flying at 1000 ft", "false" ] }, { "ans": [ "Both aircraft will fly for equal distances", "false" ] } ] }, { "ch": "What decreases as you go up in the atmosphere?", "ansGr": [ { "ans": [ "Air Pressure", "true" ] }, { "ans": [ "Atmosphere", "false" ] }, { "ans": [ "Altitude", "false" ] } ] }, { "ch": "What is another name for Newton’s first law?", "ansGr": [ { "ans": [ "Law of inertia", "true" ] }, { "ans": [ "Law of infinite motion", "false" ] }, { "ans": [ "Law of friction", "false" ] } ] }, { "ch": "What does speed of the fluid happen ,when a fluid's pressure decreases, according to Bernoulli's principle ?", "ansGr": [ { "ans": [ "It increases", "true" ] }, { "ans": [ "It decreases", "false" ] }, { "ans": [ "It stays the same", "false" ] } ] }, { "ch": "Which laws state that for every action, there is an equal and opposite reaction ?", "ansGr": [ { "ans": [ "Newtons 3rd law", "true" ] }, { "ans": [ "Newtons 2nd law", "false" ] }, { "ans": [ "Newtons 1st law", "false" ] } ] }, { "ch": "How many main forces are there that act upon an aircraft inflight?", "ansGr": [ { "ans": [ "4", "true" ] }, { "ans": [ "2", "false" ] }, { "ans": [ "3", "false" ] } ] }, { "ch": "What is the vertical component of the aerodynamic resultant ?", "ansGr": [ { "ans": [ "Lift", "true" ] }, { "ans": [ "Total aerodynamic force", "false" ] }, { "ans": [ "Drag", "false" ] } ] }, { "ch": "How many most common drag are there that upon an aircraft inflight?", "ansGr": [ { "ans": [ "3", "true" ] }, { "ans": [ "2", "false" ] }, { "ans": [ "4", "false" ] } ] }, { "ch": "What determines the coefficient of lift?", "ansGr": [ { "ans": [ "Aerofoil shape and angle of attack", "true" ] }, { "ans": [ "The aircraft designer", "false" ] }, { "ans": [ "The amount of camber", "false" ] } ] }, { "ch": "Where does the downwash occurs?", "ansGr": [ { "ans": [ "At the trailing edge only", "true" ] }, { "ans": [ "At both the leading edge and the trailing edge", "false" ] }, { "ans": [ "At the leading edge only", "false" ] } ] }, { "ch": "Which of the following can reduce induced drag?", "ansGr": [ { "ans": [ "Winglets", "true" ] }, { "ans": [ "Smooth surfaces", "false" ] }, { "ans": [ "Streamlining", "false" ] } ] }, { "ch": "What is the difference between the mean camber line and the chord line of an aerofoil ?", "ansGr": [ { "ans": [ "One is always straight and the other may be straight", "true" ] }, { "ans": [ "They both may be curved", "false" ] }, { "ans": [ "Neither are straight", "false" ] } ] }, { "ch": "What is the primary purpose of an airfoil?", "ansGr": [ { "ans": [ "To generate lift", "true" ] }, { "ans": [ "To reduce drag", "false" ] }, { "ans": [ "To increase thrust", "false" ] } ] }, { "ch": "Which statement is correct about the Cl and angle of attack?", "ansGr": [ { "ans": [ "For a symmetric aerofoil, if angle of attack = 0, Cl =0", "true" ] }, { "ans": [ "For an asymmetric aerofoil, if angle of attack = 0, Cl =0", "false" ] }, { "ans": [ "For a symmetric aerofoil, if angle of attack = 0, Cl is not equal to 0", "false" ] } ] }, { "ch": "How is the induced drag of an aircraft ?", "ansGr": [ { "ans": [ "Decreases with increasing speed", "true" ] }, { "ans": [ "Increases with increasing speed", "false" ] }, { "ans": [ "Increases if aspect ratio is increased", "false" ] } ] }, { "ch": "Which of the following factors affects the lift produced by an airfoil?", "ansGr": [ { "ans": [ "All of the above", "true" ] }, { "ans": [ "Angle of attack", "false" ] }, { "ans": [ "Velocity of airflow", "false" ] } ] }, { "ch": "What is the term for the maximum angle of attack before airflow separates from the airfoil?", "ansGr": [ { "ans": [ "Stalling angle", "true" ] }, { "ans": [ "Critical angle", "false" ] }, { "ans": [ "Lift limit", "false" ] } ] }, { "ch": "What is the effect of increasing the airspeed on the lift generated by an airfoil?", "ansGr": [ { "ans": [ "Increases lift", "true" ] }, { "ans": [ "Decreases lift", "false" ] }, { "ans": [ "Reduces drag", "false" ] } ] }, { "ch": "What type of drag is primarily caused by the shape of an object moving through a fluid?", "ansGr": [ { "ans": [ "Form drag", "true" ] }, { "ans": [ "Parasitic drag", "false" ] }, { "ans": [ "Induced drag", "false" ] } ] }, { "ch": "Which factor primarily influences induced drag?", "ansGr": [ { "ans": [ "Angle of attack", "true" ] }, { "ans": [ "Wing area", "false" ] }, { "ans": [ "Airspeed", "false" ] } ] }, { "ch": "Which of the following is a method to reduce form drag on an aircraft?", "ansGr": [ { "ans": [ "Streamlining the shape of the aircraft", "true" ] }, { "ans": [ "Increasing wing area", "false" ] }, { "ans": [ "Increasing the angle of attack", "false" ] } ] }, { "ch": "What is the relationship between lift and drag in an aircraft?", "ansGr": [ { "ans": [ "Lift and drag are both affected by angle of attack", "true" ] }, { "ans": [ "They are independent of each other", "false" ] }, { "ans": [ "Lift and drag are inversely proportional", "false" ] } ] }, { "ch": "When does the angle of incidence change?", "ansGr": [ { "ans": [ "It never changes", "true" ] }, { "ans": [ "When the aircraft attitude changes.", "false" ] }, { "ans": [ "When the aircraft is ascending or descending.", "false" ] } ] }, { "ch": "What is the effect of a high aspect ratio on an aircraft’s performance?", "ansGr": [ { "ans": [ "Increased lift efficiency", "true" ] }, { "ans": [ "Increased drag", "false" ] }, { "ans": [ "Decreased stability", "false" ] } ] }, { "ch": "What is the significance of the airfoil’s camber?", "ansGr": [ { "ans": [ "It impacts the lift and drag characteristics", "true" ] }, { "ans": [ "It affects the shape of the wing", "false" ] }, { "ans": [ "It determines the weight of the aircraft", "false" ] } ] }, { "ch": "What happens to lift as the air density decreases?", "ansGr": [ { "ans": [ "Lift decreases", "true" ] }, { "ans": [ "Lift increases", "false" ] }, { "ans": [ "Lift remains constant", "false" ] } ] }, { "ch": "What is the primary aerodynamic benefit of using winglets on aircraft wings?", "ansGr": [ { "ans": [ "Improved fuel efficiency by reducing induced drag", "true" ] }, { "ans": [ "Increased drag", "false" ] }, { "ans": [ "Greater stability", "false" ] } ] }, { "ch": "Which equation relates the lift force to air density, velocity, wing area, and coefficient of lift?", "ansGr": [ { "ans": [ "The lift equation", "true" ] }, { "ans": [ "Bernoulli’s equation", "false" ] }, { "ans": [ "Newton’s law of motion", "false" ] } ] }, { "ch": "What is the primary effect of turbulence on an aircraft?", "ansGr": [ { "ans": [ "Increased drag and potential loss of control", "true" ] }, { "ans": [ "Increased lift", "false" ] }, { "ans": [ "Decreased drag", "false" ] } ] }, { "ch": "What is the layer of air over the surface of an aerofoil which is slower moving, in relation to the rest of the airflow?", "ansGr": [ { "ans": [ "Boundary layer", "true" ] }, { "ans": [ "Camber layer", "false" ] }, { "ans": [ "None of the above", "false" ] } ] }, { "ch": "Which of the following factors does NOT directly affect drag?", "ansGr": [ { "ans": [ "Fuel type", "true" ] }, { "ans": [ "Velocity", "false" ] }, { "ans": [ "Surface area", "false" ] } ] }, { "ch": "What happens to the pressure above an airfoil as airspeed increases?", "ansGr": [ { "ans": [ "Decreases", "true" ] }, { "ans": [ "Increases", "false" ] }, { "ans": [ "Remains constant", "false" ] } ] }, { "ch": "What is the relationship between speed and lift in an aircraft?", "ansGr": [ { "ans": [ "Lift increases with increasing speed", "true" ] }, { "ans": [ "Lift decreases with increasing speed", "false" ] }, { "ans": [ "Lift increases with decreasing speed", "false" ] } ] }, { "ch": "Which of the following statements is true about turbulent airflow?", "ansGr": [ { "ans": [ "It increases drag on the aircraft.", "true" ] }, { "ans": [ "It is characterized by smooth, orderly motion.", "false" ] }, { "ans": [ "It is more efficient than laminar flow.", "false" ] } ] }, { "ch": "Which of the following statements about boundary layers is correct?", "ansGr": [ { "ans": [ "The turbulent boundary layer has more kinetic energy than the laminar boundary layer", "true" ] }, { "ans": [ "The turbulent boundary layer gives a lower skin friction than the laminar boundary layer", "false" ] }, { "ans": [ "The turbulent boundary layer is thinner than the laminar boundary layer", "false" ] } ] }, { "ch": "Which of the following types of drag increases as the aircraft gains altitude?", "ansGr": [ { "ans": [ "Induced drag.", "true" ] }, { "ans": [ "Parasite drag.", "false" ] }, { "ans": [ "Interference drag.", "false" ] } ] }, { "ch": "What would an aspect ratio of 8 : 1 mean ?", "ansGr": [ { "ans": [ "Span 64, mean chord 8.", "true" ] }, { "ans": [ "Mean chord 64, span 8.", "false" ] }, { "ans": [ "Span squared 64, chord 8.", "false" ] } ] }, { "ch": "What type of drag, depends on the smoothness of the body, and surface area over which the air flows?", "ansGr": [ { "ans": [ "Skin friction drag.", "true" ] }, { "ans": [ "Parasite drag.", "false" ] }, { "ans": [ "Form drag.", "false" ] } ] }, { "ch": "Which basic flight force is responsible for moving the airplane forward?", "ansGr": [ { "ans": [ "Thrust", "true" ] }, { "ans": [ "Lift", "false" ] }, { "ans": [ "Drag", "false" ] } ] }, { "ch": "What do the force act opposite to the direction of airplane motion?", "ansGr": [ { "ans": [ "Drag", "true" ] }, { "ans": [ "Thrust", "false" ] }, { "ans": [ "Lift", "false" ] } ] }, { "ch": "Which of the following is correct for steady level flight?", "ansGr": [ { "ans": [ "Thrust = Drag", "true" ] }, { "ans": [ "Thurst > Drag", "false" ] }, { "ans": [ "Thrust < Drag", "false" ] } ] }, { "ch": "Which of the following is correct for glide ratio of an airplane ?", "ansGr": [ { "ans": [ "The distance the airplane will, with power off, travel forward in relation to the altitude it loses.", "true" ] }, { "ans": [ "The distance the airplane will, with power on, travel forward in relation to the altitude it loses", "false" ] }, { "ans": [ "The distance the airplane will, with power off, travel forward in relation to the altitude it increases", "false" ] } ] }, { "ch": "What is the glide ratio affected by ?", "ansGr": [ { "ans": [ "Thurst, drag, weight, lift", "true" ] }, { "ans": [ "Wind, speed, lift, drag", "false" ] }, { "ans": [ "Thust, drag, velocity", "false" ] } ] }, { "ch": "What force makes an airplane turn?", "ansGr": [ { "ans": [ "The horizontal component of lift", "true" ] }, { "ans": [ "The vertical component of the Lift", "false" ] }, { "ans": [ "Centrifugal force", "false" ] } ] }, { "ch": "What do load factors mean ?", "ansGr": [ { "ans": [ "The ratio of a specified load to the weight of the aircraft, the former being expressed in terms of aerodynamic forces, inertia forces and ground reactions", "true" ] }, { "ans": [ "The ratio of a specified load to the mass of the aircraft, the former being expressed in terms of aerodynamic forces, inertia forces and ground reactions", "false" ] }, { "ans": [ "The ratio of a specified load to the mass of the aircraft the former being expressed in terms of aerodynamic and inertia forces", "false" ] } ] }, { "ch": "When does an aircraft stalls ?", "ansGr": [ { "ans": [ "Lift decreases and drag increases.", "true" ] }, { "ans": [ "Lift and drag increase.", "false" ] }, { "ans": [ "Lift increases and drag decreases.", "false" ] } ] }, { "ch": "Which of the following is correct for airplane in turn?", "ansGr": [ { "ans": [ "Extra lift is required", "true" ] }, { "ans": [ "Extra lift is not required", "false" ] }, { "ans": [ "Extra lift is not required if thrust is increased", "false" ] } ] }, { "ch": "Which type of airflow occurs when the airspeed exceeds the speed of sound?", "ansGr": [ { "ans": [ "Supersonic", "true" ] }, { "ans": [ "Transonic", "false" ] }, { "ans": [ "Subsonic", "false" ] } ] }, { "ch": "What occurs during a stall in an aircraft?", "ansGr": [ { "ans": [ "Loss of lift due to airflow separation", "true" ] }, { "ans": [ "Increase in speed", "false" ] }, { "ans": [ "Increase in drag", "false" ] } ] }, { "ch": "What is an airplane stall ?", "ansGr": [ { "ans": [ "Decrease in lift , separation of airflow , exceeding the critical AOA .", "true" ] }, { "ans": [ "Decrease in lift , separation of airflow , not exceeding the critical AOA.", "false" ] }, { "ans": [ "Increase in lift , separation of airflow ,exceeding the critical AOA", "false" ] } ] }, { "ch": "When does an airplane reach critical AOA ?", "ansGr": [ { "ans": [ "Since the Cl increases with an increase in AOA, Cl reachs CL-max.", "true" ] }, { "ans": [ "Turn aircraft", "false" ] }, { "ans": [ "Since the Cl decreases with an increase in AOA", "false" ] } ] }, { "ch": "What do factors efect to stall ?", "ansGr": [ { "ans": [ "Center of gravity location, load factor , power , total weight", "true" ] }, { "ans": [ "Drag , fuel , engine", "false" ] }, { "ans": [ "Turbulence , eng power , pilot , fuel", "false" ] } ] }, { "ch": "How do pilots recover stall ?", "ansGr": [ { "ans": [ "Control : Nose down , increase speed", "true" ] }, { "ans": [ "Control : Nose down , decrease speed", "false" ] }, { "ans": [ "Control : Nose up , increase speed", "false" ] } ] }, { "ch": "Why does the nose up rotation also produces additional lift on the wing ?", "ansGr": [ { "ans": [ "The increasing angle of attack.", "true" ] }, { "ans": [ "The decreasing angle of attack.", "false" ] }, { "ans": [ "The decreasing angle of incidence.", "false" ] } ] }, { "ch": "When an aircraft is in constant altitude, wings level flight, the lift is?", "ansGr": [ { "ans": [ "Equal to the weight of the aircraft.", "true" ] }, { "ans": [ "Smaller to the weight of the aircraft.", "false" ] }, { "ans": [ "Bigger to the weight of the aircraft.", "false" ] } ] }, { "ch": "How is the lift in the turn , If the aircraft is to maintain altitude during a turn ?", "ansGr": [ { "ans": [ "Must be equal to the resultant of the centrifugal force and the weight..", "true" ] }, { "ans": [ "Must not be equal to the resultant of the centrifugal force and the weight", "false" ] }, { "ans": [ "Must be equal to the resultant of the centrifugal force or the weight.", "false" ] } ] }, { "ch": "How is the speed in the subsonic region?", "ansGr": [ { "ans": [ "So slow that a flying body does not compress the air.", "true" ] }, { "ans": [ "Constant.", "false" ] }, { "ans": [ "So high that a flying body does not compress the air.", "false" ] } ] }, { "ch": "Whati is an airplane glide ratio, if it travels 10000 feet forward while descending 1000 feet ?", "ansGr": [ { "ans": [ "10 to 1", "true" ] }, { "ans": [ "100 to 1", "false" ] }, { "ans": [ "1 to 1", "false" ] } ] }, { "ch": "What forces is glide ratio affected by?", "ansGr": [ { "ans": [ "Weight, lift, drag, and thrust", "true" ] }, { "ans": [ "Lift, drag, thrust", "false" ] }, { "ans": [ "Drag, lift, weight", "false" ] } ] }, { "ch": "What is the primary aerodynamic force that acts perpendicular to the direction of flight and contributes to turning an aircraft ?", "ansGr": [ { "ans": [ "Lift", "true" ] }, { "ans": [ "Drag", "false" ] }, { "ans": [ "Thrust", "false" ] } ] }, { "ch": "What is the name of force that pulls the aircraft outward in a turn, acting opposite to the center of the turn ?", "ansGr": [ { "ans": [ "Centrifugal force", "true" ] }, { "ans": [ "Lift", "false" ] }, { "ans": [ "Thrust", "false" ] } ] }, { "ch": "Why does an aircraft need to increase its angle of attach during a turn ?", "ansGr": [ { "ans": [ "To maintain lift sufficient to counteract both gravity and the forces of the turn.", "true" ] }, { "ans": [ "To reduce drag and maintain speed.", "false" ] }, { "ans": [ "To decrease the lift-to-drag ratio for smoother turn.", "false" ] } ] }, { "ch": "What is the load factor in aerodynamics?", "ansGr": [ { "ans": [ "The ratio of the maximum load an aircraft can sustain to the gross weight of the aircraft", "true" ] }, { "ans": [ "The maximum thrust an aircraft engine can produce.", "false" ] }, { "ans": [ "The speed at which the aircraft's structural integrity is tested.", "false" ] } ] }, { "ch": "Why does the stall speed increase as the load factor increases?", "ansGr": [ { "ans": [ "The effective weight of aircraft increases , requiring more lift to maintain level flight.", "true" ] }, { "ans": [ "The aircraft loses lift as the wings are banked.", "false" ] }, { "ans": [ "The drag decreases and affects the airflow over the wings.", "false" ] } ] }, { "ch": "Which category of aircraft has the highest allowable positive limit load factor ?", "ansGr": [ { "ans": [ "Acrobatic", "true" ] }, { "ans": [ "Normal", "false" ] }, { "ans": [ "Utility", "false" ] } ] }, { "ch": "What is a common consequence of exceeding the critical Mach number in high-speed flight?", "ansGr": [ { "ans": [ "Formation of a shock wave on the wing", "true" ] }, { "ans": [ "Loss of engine power", "false" ] }, { "ans": [ "Increased fuel efficiency", "false" ] } ] }, { "ch": "What is the primary aerodynamic benefit of a wing with sweepback in high-speed flight ?", "ansGr": [ { "ans": [ "Delayed onset of shockwaves and reduced drag at transonic and supersonic speeds.", "true" ] }, { "ans": [ "Increased lift at low speeds.", "false" ] }, { "ans": [ "Improved fuel efficiency during takeoff", "false" ] } ] }, { "ch": "How does reaching the critical Mach number effect the drag coefficient of an aircraft ?", "ansGr": [ { "ans": [ "The drag coefficient increases sharply due to the formation of shock waves.", "true" ] }, { "ans": [ "The drag coefficient remains constant.", "false" ] }, { "ans": [ "The drag coefficient decreases as airflow becomes smoother.", "false" ] } ] }, { "ch": "What is the critical Mach number of an aircraft?", "ansGr": [ { "ans": [ "The Mach number at which the first shock wave forms on the aircraft, causing a rapid increase in drag.", "true" ] }, { "ans": [ "The Mach number at which the aircraft reaches supersonic speeds.", "false" ] }, { "ans": [ "The Mach number at which lift is zero.", "false" ] } ] }, { "ch": "Which flap will increase wing area and camber?", "ansGr": [ { "ans": [ "Fowler.", "true" ] }, { "ans": [ "Slot.", "false" ] }, { "ans": [ "Split.", "false" ] } ] }, { "ch": "What is the main characteristic of a swept-wing design?", "ansGr": [ { "ans": [ "Improved high-speed performance", "true" ] }, { "ans": [ "Increased drag", "false" ] }, { "ans": [ "Greater lift generation", "false" ] } ] }, { "ch": "What is a key characteristic of a secondary flight controls ?", "ansGr": [ { "ans": [ "It increases lift at lower speeds", "true" ] }, { "ans": [ "It is only used during cruising", "false" ] }, { "ans": [ "It increases drag significantly", "false" ] } ] }, { "ch": "What is the primary function of vortex generators on an aircraft wing ?", "ansGr": [ { "ans": [ "To promote positive laminar airflow over the wing and control surfaces.", "true" ] }, { "ans": [ "To decrease the wing's weight.", "false" ] }, { "ans": [ "To improve the lift coefficient at low speeds.", "false" ] } ] }, { "ch": "How does a stall fence improve the safety of an aircraft during flight?", "ansGr": [ { "ans": [ "By preventing premature flow seperation near the wing tips.", "true" ] }, { "ans": [ "By increasing thrust at high altitudes.", "false" ] }, { "ans": [ "By allowing the pilot to fly at a higher speed.", "false" ] } ] }, { "ch": "Why does the speed of sound increase with temperature?", "ansGr": [ { "ans": [ "Warmer air allows faster movement of pressure waves", "true" ] }, { "ans": [ "Sound intensity increases with decreasing altitude", "false" ] }, { "ans": [ "Colder air contains less sound resistance", "false" ] } ] }, { "ch": "How are sound waves generated?", "ansGr": [ { "ans": [ "By disturbances in airflow around aircraft surfaces", "true" ] }, { "ans": [ "By vibration of the aircraft's engines and landing gear", "false" ] }, { "ans": [ "By electric signals between cockpit and fuselage", "false" ] } ] }, { "ch": "What defines transonic flight?", "ansGr": [ { "ans": [ "When some parts of the airflow are subsonic and others are supersonic", "true" ] }, { "ans": [ "When the aircraft reaches Mach 2.0 at high altitude", "false" ] }, { "ans": [ "When flight exceeds Mach 3 regardless of air density", "false" ] } ] }, { "ch": "Why does the center of lift shift during transonic flight?", "ansGr": [ { "ans": [ "The shock wave alters pressure distribution over the wing", "true" ] }, { "ans": [ "The angle of attack is reduced automatically", "false" ] }, { "ans": [ "Aircraft speed drops below minimum stall speed", "false" ] } ] }, { "ch": "What happens behind a normal shock wave?", "ansGr": [ { "ans": [ "The air becomes subsonic", "true" ] }, { "ans": [ "The air remains supersonic", "false" ] }, { "ans": [ "The air accelerates and becomes turbulent", "false" ] } ] }, { "ch": "How do oblique shock waves differ from normal shock waves?", "ansGr": [ { "ans": [ "They are angled and maintain supersonic flow behind them", "true" ] }, { "ans": [ "They reflect sound backward to reduce wave interference", "false" ] }, { "ans": [ "They are circular and cause expansion of airflow", "false" ] } ] }, { "ch": "Why is the critical Mach number important for aircraft design?", "ansGr": [ { "ans": [ "It marks the onset of shock-related airflow disturbances", "true" ] }, { "ans": [ "It shows when the aircraft’s wing becomes fully stalled", "false" ] }, { "ans": [ "It causes the engines to lose synchronization", "false" ] } ] }, { "ch": "What effect occurs just above the critical Mach number?", "ansGr": [ { "ans": [ "Buffet and drag rise begin to occur", "true" ] }, { "ans": [ "Lift reduces while thrust becomes unstable", "false" ] }, { "ans": [ "Thrust reversers activate automatically", "false" ] } ] }, { "ch": "How does wing sweepback influence critical Mach number?", "ansGr": [ { "ans": [ "It delays the formation of shock waves", "true" ] }, { "ans": [ "It makes the wing more flexible for high-speed turns", "false" ] }, { "ans": [ "It shifts the center of gravity rearward", "false" ] } ] }, { "ch": "What aerodynamic benefit does sweepback offer during drag rise?", "ansGr": [ { "ans": [ "It reduces sudden changes in aerodynamic forces", "true" ] }, { "ans": [ "It reduces wing thickness and increases fuel storage", "false" ] }, { "ans": [ "It deflects shockwaves toward the fuselage", "false" ] } ] }, { "ch": "Why do supersonic aircraft require different wing shapes?", "ansGr": [ { "ans": [ "To maintain control at compressible speeds", "true" ] }, { "ans": [ "To reduce engine vibration at low altitude", "false" ] }, { "ans": [ "To reduce ground effect during approach", "false" ] } ] }, { "ch": "What causes compressibility buffet?", "ansGr": [ { "ans": [ "Airflow reaches Mach 1 over localized wing surfaces", "true" ] }, { "ans": [ "Drag becomes zero over upper wing surfaces", "false" ] }, { "ans": [ "Lift becomes constant over the entire wing", "false" ] } ] }, { "ch": "Why was titanium used in the SR-71 Blackbird construction?", "ansGr": [ { "ans": [ "To resist heat from air friction at high Mach speeds", "true" ] }, { "ans": [ "To increase aerodynamic lift during descent", "false" ] }, { "ans": [ "To manage electrical heating in wing de-icing", "false" ] } ] }, { "ch": "What structural issue led to Concorde reducing its cruise speed?", "ansGr": [ { "ans": [ "Aerodynamic heating caused structural stress", "true" ] }, { "ans": [ "Engine vibration increased during climb", "false" ] }, { "ans": [ "Passenger comfort needed to be improved", "false" ] } ] }, { "ch": "What is the main benefit of applying the area rule to aircraft design?", "ansGr": [ { "ans": [ "To reduce drag by smoothing cross-sectional transitions", "true" ] }, { "ans": [ "To stabilize fuel pressure near the wing root", "false" ] }, { "ans": [ "To reduce lift along the wingtips at cruise", "false" ] } ] }, { "ch": "How is the area rule applied across the aircraft structure?", "ansGr": [ { "ans": [ "By shaping total cross-sectional area, including wings and fuselage", "true" ] }, { "ans": [ "By reducing wing loading at cruise condition", "false" ] }, { "ans": [ "By adding circular shaping to the tail cone", "false" ] } ] }, { "ch": "Why do subsonic aircraft use divergent ducts for engine intake?", "ansGr": [ { "ans": [ "To reduce airflow velocity before engine compression", "true" ] }, { "ans": [ "To accelerate the air into the combustion chamber", "false" ] }, { "ans": [ "To cool down the fuel before ignition", "false" ] } ] }, { "ch": "How is supersonic intake airflow controlled?", "ansGr": [ { "ans": [ "By shaping the duct and using valves to adjust speed", "true" ] }, { "ans": [ "By changing exhaust gas flow rate at high speed", "false" ] }, { "ans": [ "By injecting compressed air near the nozzle", "false" ] } ] }, { "ch": "What is the lateral axis called ?", "ansGr": [ { "ans": [ "Pitch axis", "true" ] }, { "ans": [ "Normal axis", "false" ] }, { "ans": [ "Roll axis", "false" ] } ] }, { "ch": "What is Movement of an aircraft about its vertical axis ?", "ansGr": [ { "ans": [ "Yawing", "true" ] }, { "ans": [ "Pitching", "false" ] }, { "ans": [ "Rolling", "false" ] } ] }, { "ch": "What is the lateral axis?", "ansGr": [ { "ans": [ "A straight line through the CG parallel to a line joining the wingtips", "true" ] }, { "ans": [ "A straight line through the CG from nose to tail", "false" ] }, { "ans": [ "A straight line through the CG at right angles to the longitudinal and lateral axis", "false" ] } ] }, { "ch": "What is the directional axis ?", "ansGr": [ { "ans": [ "Acts through the C of G, perpendicular to the longitudinal axis and lateral axis", "true" ] }, { "ans": [ "Perpendicular to the longitudinal axis", "false" ] }, { "ans": [ "Perpendicular to the horizontal axis", "false" ] } ] }, { "ch": "What is stability if an aircraft returns to a position of equilibrium?", "ansGr": [ { "ans": [ "Positively stablity", "true" ] }, { "ans": [ "Neutrally stablity", "false" ] }, { "ans": [ "Negatively stablity", "false" ] } ] }, { "ch": "What is the lateral stability about ?", "ansGr": [ { "ans": [ "Longitudinal axis", "true" ] }, { "ans": [ "Vertical axis", "false" ] }, { "ans": [ "Lateral axis", "false" ] } ] }, { "ch": "Which component contributes the most to the longitudinal stability of an aircraft?", "ansGr": [ { "ans": [ "The horizontal stabilizer", "true" ] }, { "ans": [ "The vertical stabilizer", "false" ] }, { "ans": [ "The landing gear", "false" ] } ] }, { "ch": "What is Stability of an aircraft ?", "ansGr": [ { "ans": [ "The tendency of the aircraft to return to its original trimmed position after having been displaced", "true" ] }, { "ans": [ "The tendency of the aircraft to stall at low airspeed", "false" ] }, { "ans": [ "The ability of the aircraft to rotate about an axis", "false" ] } ] }, { "ch": "How does the position of the center of gravity affect an aircraft’s stability?", "ansGr": [ { "ans": [ "A forward center of gravity increases stability", "true" ] }, { "ans": [ "A rearward center of gravity increases stability", "false" ] }, { "ans": [ "The position of the center of gravity has no effect", "false" ] } ] }, { "ch": "What is the main purpose of a dihedral angle in wing design?", "ansGr": [ { "ans": [ "To improve roll stability", "true" ] }, { "ans": [ "To increase lift", "false" ] }, { "ans": [ "To decrease drag", "false" ] } ] }, { "ch": "Which of the following controls the pitch of an aircraft?", "ansGr": [ { "ans": [ "Elevator", "true" ] }, { "ans": [ "Rudder", "false" ] }, { "ans": [ "Flaps", "false" ] } ] }, { "ch": "How can we say that the aircraft has initial tendency to return to its original equilibrium position after being disturbed?", "ansGr": [ { "ans": [ "If aircraft generates some restoring force or/and moment without any external help", "true" ] }, { "ans": [ "If lift is same as weight always", "false" ] }, { "ans": [ "If thrust loading is always unity", "false" ] } ] }, { "ch": "When do dynamic stability apply?", "ansGr": [ { "ans": [ "Dynamic stability only applies if we have positive static stability.", "true" ] }, { "ans": [ "Dynamic stability only applies if we have neutral static stability.", "false" ] }, { "ans": [ "Dynamic stability only applies if we have negative static stability.", "false" ] } ] }, { "ch": "What does The longitudinal stability depend on?", "ansGr": [ { "ans": [ ".The angle of attack and the pitching moment effects of the horizontal stabilizer and the wing.", "true" ] }, { "ans": [ "The angle of incidence and the pitching moment effects of the horizontal stabilizer and the wing", "false" ] }, { "ans": [ "The angle of attack and the pitching moment effects of the vertical stabilizer and the wing.", "false" ] } ] }, { "ch": "What do we get , when a gust hits the upper front part of the aircraft ?", "ansGr": [ { "ans": [ "We get a nose down rotation.", "true" ] }, { "ans": [ "We get a nose up rotation.", "false" ] }, { "ans": [ "We get no rotation of nose.", "false" ] } ] }, { "ch": "Which axis does the aircraft rotate around when the gust moves the right wing upward and the left wing downward ?", "ansGr": [ { "ans": [ "The longitudinal axis.", "true" ] }, { "ans": [ "The lateral axis.", "false" ] }, { "ans": [ "The vertical axis.", "false" ] } ] }, { "ch": "What is the sideslip angle?", "ansGr": [ { "ans": [ "The angle between the aircraft centerline and the fuselage axis.", "true" ] }, { "ans": [ "The angle between the aircraft centerline and the wing axis.", "false" ] }, { "ans": [ "The angle between the aircraft centerline and the sideslip direction.", "false" ] } ] }, { "ch": "What is Dutch roll?", "ansGr": [ { "ans": [ "Lateral − directional oscillation", "true" ] }, { "ans": [ "Vertical − directional oscillation.", "false" ] }, { "ans": [ "Longitudinal − directional oscillation..", "false" ] } ] }, { "ch": "What does the ball do when the ball is displaced from the center on a concave surface , in static stability?", "ansGr": [ { "ans": [ "It returns to its original position of equilibrium.", "true" ] }, { "ans": [ "It moves away from its original position of equilibrium.", "false" ] }, { "ans": [ "It shows no tendency to roll back or away from its original position of equilibrium.", "false" ] } ] }, { "ch": "What does Longitudinal stability refer to?", "ansGr": [ { "ans": [ "The pitch movement around the lateral axis.", "true" ] }, { "ans": [ "The roll movement around the longitudinal axis.", "false" ] }, { "ans": [ "The yaw movement around the vertical axis.", "false" ] } ] }, { "ch": "What does Directional stability refer to?", "ansGr": [ { "ans": [ "The yaw movement around the vertical axis.", "true" ] }, { "ans": [ "The pitch movement around the lateral axis.", "false" ] }, { "ans": [ "The roll movement around the longitudinal axis.", "false" ] } ] }, { "ch": "When the position of the center of lift moves forward of the position of the center of gravity we have?", "ansGr": [ { "ans": [ "A nose up reaction.", "true" ] }, { "ans": [ "A down up reaction.", "false" ] }, { "ans": [ "No nose up or down reaction.", "false" ] } ] }, { "ch": "In addition to sweepback , what other wing feature can help enhance directional stability?", "ansGr": [ { "ans": [ "Wing dihedral", "true" ] }, { "ans": [ "Wing fences", "false" ] }, { "ans": [ "Slotted flaps", "false" ] } ] }, { "ch": "How does wing sweepback affect the directional stability of an aircraft?", "ansGr": [ { "ans": [ "It increases directional stability at high speeds", "true" ] }, { "ans": [ "It decreases directional stability at high speeds", "false" ] }, { "ans": [ "It only affects lateral stability", "false" ] } ] } ]