Demo: SPL

The correct answer is: Rudder opposite lower wing, releasing elevator to build up speed. This prevents a spin by regaining airflow and balancing the aircraft. Pulling the elevator or deflecting all controls can worsen the situation or cause loss of control.

Flying above vNE can cause flutter and mechanical damage to the wings, as the structure is overstressed. The other options are incorrect because they either misrepresent aerodynamics or describe effects that do not occur in reality.

Correct: total pressure = dynamic pressure + static pressure. This is Bernoulli's equation. The other options mix up or incorrectly add/subtract the pressures, which is not physically correct.

The correct answer is 'chord', as it is the length from the leading to the trailing edge of the airfoil. 'Angle of attack' is the angle between chord line and airflow, 'chord line' is an imaginary line, and 'profile thickness' is the maximum distance between upper and lower surfaces.

The stagnation point is where the airflow hits the aerofoil and its speed drops to zero. The transition point, separation point, and center of pressure are located elsewhere and describe different aerodynamic effects.

Wing washout keeps the aileron effective at high angles of attack. The other options are incorrect because washout does not mainly increase structural rigidity, torsion resistance, or reduce form drag at high speeds.

Pressure compensation occurs at the wing tips, where air can flow from the high-pressure underside to the low-pressure topside. At the leading edge, wing roots, and fuselage connections, this does not happen.

As speed increases, induced drag decreases because less lift per speed unit is needed. Parasite drag increases since air resistance rises with speed. The other answers are incorrect as they describe the opposite or both decreasing/increasing, which is not correct.

The correct answer is: Induced drag decreases with increasing airspeed. This is because at higher speeds, less angle of attack is needed, reducing induced drag. The other options are incorrect as they either state the opposite or suggest a minimum or maximum that does not exist in this context.

The correct answer is: decrease the angle of attack and increase the speed. This recovers from a stall. The other options are wrong because increasing the angle of attack or reducing speed would worsen or prolong the stall.

During spin recovery, ailerons should be kept neutral to avoid worsening the spin. Speed does not constantly increase during a spin, all aircraft can spin, and crossing ailerons is incorrect.

The laminar boundary layer starts at the stagnation point and ends at the transition point, where it becomes turbulent. Other options are incorrect because they mention the wrong start or end points, or use terms like center of pressure, which are not relevant here.

Wing dihedral provides lateral stability, as it helps the aircraft return to level after a roll. The vertical tail and elevator affect directional and longitudinal stability, not lateral. Differential aileron deflection is for roll control, not stability.

Longitudinal stability refers to stability around the lateral axis, which controls pitch. The vertical axis is for yaw, the longitudinal axis is for roll, and the propeller axis is not relevant for stability types.

Stability around the lateral axis (pitch axis) is mainly influenced by the longitudinal center of gravity. If the CG is too far forward or aft, the aircraft becomes unstable in pitch. The longitudinal, vertical, and gravity axes are less affected.

The elevator moves the aircraft around the lateral axis, causing the nose to pitch up or down. The vertical and longitudinal axes are controlled by other control surfaces, not the elevator. There is no 'elevator axis.'

Deflecting the rudder to the left causes yawing of the aircraft to the left, as the rudder pushes the tail right and the nose left. The other answers are incorrect because they refer to the wrong direction or to pitching, which is controlled by the elevator, not the rudder.

The advantage of differential aileron movement is that the drag of the downwards deflected aileron is reduced, making adverse yaw smaller. The other answers are incorrect because they either increase adverse yaw or are unrelated to aileron deflection effects.

Adverse yaw is compensated by differential aileron deflection, where the downward aileron moves less than the upward one. Aileron trim, wing dihedral, and full aileron deflection do not specifically address adverse yaw.

The aerodynamic rudder balance reduces the control stick forces by using design features that make it easier to move the controls. It does not reduce the control surfaces, delay the stall, or directly improve rudder effectiveness.

Wing loading is the ratio of weight to wing area. It shows how much weight is carried per square meter of wing. The other options are incorrect because they either reverse the terms or refer to drag, not weight.

In a coordinated turn, the load factor (n) is larger than 1 because more lift is needed. This also increases the stall speed (Vs) compared to straight and level flight. The other answers are incorrect as they misstate n or Vs.

During a turn, lift must be increased to balance the greater apparent weight. The other options are incorrect: the net force is higher, not lower; the horizontal lift component provides centripetal, not centrifugal force; and the net force is not just gravity plus centripetal force.

The correct answer is right because the down-deflected aileron creates more drag, causing the aircraft to yaw opposite to the roll. The other answers are wrong as they mention the wrong aileron, rudder, or describe the effect in the wrong direction.

Winglets reduce induced drag at the wingtips. They do not directly increase lift or turning ability, do not specifically improve high-speed gliding, and do not replace the efficiency gained by a higher aspect ratio.