Unit 4 Review 2

Lift on a wing is most properly defined as the __________.

The reaction of downwash causes a downward reaction according to Newton’s Third Law of Motion.

• True

• False

Which of the following is true for an airplane in steady flight? Select all that apply.

• The sum of all upward components of forces equals the sum of all downward components of forces

• The sum of all forward components of forces is greater than the sum of all backward components of forces

• The sum of all upward components of forces equals the sum of all forward components of forces

• The sum of all forward components of forces is greater than the sum of all downward components of forces

• The sum of all forward components of forces equals the sum of backward components of forces

Which of the following is true relative to a changing angle of attack?

• A decrease in angle of attack will increase the pressure below the wing and increase drag

• An increase in angle of attack will decrease the pressure above the wing and increase lift

• An increase in angle of attack will increase the pressure above the wing and increase drag

• An decrease in angle of attack will increase lift

The Longer Path theory (or Equal Transit Time theory) says that the molecules of air flowing over the top of a wing must travel faster than the molecules of air flowing beneath the wing in order to meet at the trailing (back) edge. What is the problem with this theory?

• It assumes that molecules of air arriving at the front of the wing are divided equally above and below the wing.

• It assumes that molecules move at the same speed regardless of how fast air flows above and below the wing.

• It assumes that molecules of air arriving at the front of the wing at the same time must also arrive at the back edge of the wing at the same time.

• It assumes that more air travels above the wing than below the wing.

If the velocity of an airplane is doubled, the lift will _________.

• increase by a factor of 2

• increase by a factor of 4

• decrease by a factor of 4

• decrease by a factor of 2

An aircraft always stalls at the same _________ regardless of airspeed, weight, or any other factor.

• velocity

• angle of attack

• altitude

• acceleration

What safety measures do airplane designers take in regard to stalls? Select all that apply.

• Ensure the airplane is as controllable as possible during a stall.

• Ensure a stall is delayed as long as possible.

• Ensure the pilot is warned of a possible stall.

• All of the above

The center of gravity of an airplane can be determined by which method? (4.C.1)

• Dividing total moments by total weight

• Multiplying total moments by total weight

• Multiplying total arms by total moments

• Dividing total arms by total weight

What can happen when the center of gravity (CG) of an airplane is forward of its acceptable CG range? (4.C.1)

• Rudder effectiveness is limited creating insufficient nose-up force for landing.

• Rudder effectiveness is limited creating insufficient nose-down force for landing.

• Elevator effectiveness is limited creating insufficient nose-up force for landing.

• Elevator effectiveness becomes limited creating insufficient nose-up force for landing.