Flight Controls practice questions

Answer: B) The raised aileron's nose projects into the airflow and adds drag

• AIncorrect. Frise ailerons move both ways.
• BCorrect. The extra drag offsets adverse yaw.
• CIncorrect. They act on one wing at a time.
• DIncorrect. They do not affect rudder locks.

Answer: A) Mix high-energy airflow into the boundary layer to delay flow separation

Vortex generators are small airfoil-shaped vanes. They energize the boundary layer by mixing in high-energy air, which delays flow separation and keeps control surfaces effective.

• ACorrect. The vanes create small vortices that bring faster outside air into the slow boundary layer. This delays separation and keeps the ailerons effective at high angles of attack.
• BIncorrect. Static dischargers (wicks) do this. They are usually mounted on trailing edges and wingtips.
• CIncorrect. Stall strips do this. They are sharp strips on the inboard leading edge that cause separation, which is the opposite of what vortex generators do.
• DIncorrect. Reducing spanwise flow is the job of wing fences and winglets. Vortex generators work on the boundary layer to prevent separation.

Answer: C) It moves the rudder automatically in response to sensed yaw rate to damp Dutch roll oscillations

A yaw damper is a servo that moves the rudder in response to sensed yaw rate or lateral acceleration. It damps Dutch roll and turbulence-induced yaw, which is especially important on swept-wing airplanes.

• AIncorrect. Limiting rudder travel with airspeed is done by a rudder limiter or ratio changer, not the yaw damper.
• BIncorrect. That is the job of a gust lock. A yaw damper works in flight.
• CCorrect. The yaw damper is a servo that moves the rudder based on gyro or accelerometer inputs. It reduces yaw motion and damps Dutch roll, which matters most on swept-wing airplanes.
• DIncorrect. A steady correction for asymmetric thrust comes from rudder trim or pilot input. The yaw damper makes continuous small corrections against oscillation.

Answer: B) Flaperon

A flaperon is a wing trailing-edge surface that works as an aileron for roll control and as a flap when both sides deflect down together.

• AIncorrect. An elevon combines aileron and elevator functions (roll and pitch), usually on tailless or delta-wing aircraft. It does not act as a flap.
• BCorrect. A flaperon does the job of both an aileron (moving differentially for roll) and a flap (moving down together to change lift and drag).
• CIncorrect. A stabilator is a one-piece movable horizontal tail used for pitch control, not a wing surface.
• DIncorrect. A ruddervator is the movable surface on a V-tail that combines rudder and elevator functions. It is not on the wing.

Answer: C) Rudder and elevator

On a V-tail, the two slanted surfaces replace the conventional horizontal and vertical tail, and their movable ruddervators do the work of both the elevator (pitch) and the rudder (yaw).

• AIncorrect. A surface that combines aileron and elevator functions is an elevon, typically found on tailless or delta-wing aircraft, not on a V-tail.
• BIncorrect. A wing trailing-edge surface that combines aileron and flap functions is a flaperon, not a tail surface.
• CCorrect. The V-tail's fixed surfaces act as both horizontal and vertical stabilizers, and their movable surfaces (ruddervators) give pitch control like an elevator and yaw control like a rudder.
• DIncorrect. A one-piece movable horizontal tail that combines the stabilizer and elevator is a stabilator. It provides pitch control only, not yaw control.

Answer: B) Leading-edge flaps that hinge down from below

• AIncorrect. Spoilers are on top of the wing.
• BCorrect. They increase lift at low speed.
• CIncorrect. They are leading-edge devices.
• DIncorrect. They are on the leading edge.

Answer: C) Delay the stall

• AIncorrect. Spoilers do that.
• BIncorrect. They are for low-speed flight.
• CCorrect. Slats let the wing reach a higher angle of attack before stalling.
• DIncorrect. This is unrelated.

Answer: B) Measure the swaged shank of the fitting with a go/no-go gauge for proper compression

A swaged terminal is checked with a go/no-go gauge to confirm proper compression. A paint mark at the junction is used afterward to detect cable slippage, not to verify the swage.

• AIncorrect. Painting the junction is a real practice, but it lets later inspections spot cable slippage by showing a gap in the paint. It does not confirm that the fitting was compressed to the right size.
• BCorrect. AC 43.13-1B says to check the swaged fitting with a go/no-go gauge to confirm it is properly compressed, and also to inspect the finished terminal's physical condition.
• CIncorrect. Tap testing is used to find delaminations in composite and bonded structures. It cannot measure how much a metal fitting was compressed.
• DIncorrect. Loading the cable until it yields would damage the assembly. Proof testing, when required, stays well below breaking strength. The size check after swaging is done with a gauge.

Answer: A) Clip-locking devices or safety wire

• ACorrect. Both methods prevent the barrel from turning.
• BIncorrect. Sealant is not an approved turnbuckle safety.
• CIncorrect. Cables are never drilled for cotter pins.
• DIncorrect. Turnbuckles must always be safetied.

Answer: B) Transmits rotary motion to a surface

• AIncorrect. A tensiometer measures tension.
• BCorrect. Torque tubes twist to move flaps, ailerons and similar surfaces.
• CIncorrect. Mass balance and dampers address flutter.
• DIncorrect. Reservoirs store fluid.