Aerodynamics and Aircraft Stability Concepts

Loading an airplane to the most aft CG will cause the airplane to be

• less stable at all speeds

• less stable at slow speeds, but more stable at high speeds

• less stable at high speeds, but more stable at low speeds

An airplane loaded with Center of Gravity(CG) rear of the aft CH limit could

• make it easier to recover from stalls and spins

• make it more difficult to flare for landing

• increase the likelihood of inadvertent overstress

What is the relationship of lift, drag, thrust, and weight when the aircraft is in straight-and-level flight?

• Lift equals weight and thrust equals drag

• Lift, drag, and weight equal thrust

• Lift and weight equal thrust and drag

The acute angle A is the angle of

• incidence

• attack

• dihedral

The angle between the chord line of an airfoil and the relative wind is known as the angle of

• lift

• attack

• incidence

What determines the longitudinal stability of an airplane?

• The location of the CG with respect to the center of lift

• The effectiveness of the horizontal stabilizer, rudder, and rudder trim tab

• The relationship of thrust and lift to weight and drag

An airplane said to be inherently stable will

• be difficult to stall

• require less effort to control

• not spin

What causes an airplane (expect a T-tail) to pitch nosedown when power is reduced and controls are not adjusted

• The CG shifts forward when thrust and drag are reduced

• The downwash on the elevators from the propeller slipstreams is

• When thrust is reduced to less than weight, lift is also reduced and the wings can no longer support the weight

What is the effect of advancing the throttle in flight?

• Both aircraft groundspeed and angle of attack will increase

• Airspeed will remain relatively constant but the aircraft will climb

• The aircraft will accelerate, which will cause a turn to the right

What is the effect of advancing the throttle in flight?

• Both aircraft groundspeed and angle of attack will increase

• Airspeed will remain relatively constant but the aircraft will climb

• The aircraft will accelerate, which will cause a turn to the right