Lateral Stability

Question 1

What is lateral Stability?

Answer 1

it is the stability around the LONGITUDINAL AXIS and is called the ROLL STABILTIY

Question 2

Lateral stability is achieved through…

Answer 2

1) Dihedral
2) Sweep-back
3) kneel effect
4) Proper distribution of weight

Question 3

What is dihedral?

Answer 3

Dihedral is the angle each wing makes with the HORIZONTAL

Question 4

what is the purpose of dihedral?

Answer 4

The purpose of dihedral is to improve lateral stability

Question 5

What is a anhedral?

Answer 5

Some modern planes have a measure of negative dihedral on the wings or stabilizers

Question 6

dihedral is usually a feature on what types of planes?

Answer 6

usually a feature on low wing airplanes although some dihedral can be incorporated in high wing airplanes as well

Question 7

What is the keel effect?

Answer 7

most high wing airplanes are laterally stable because the wings are attached in a high position on the fuselage and because the weight is therefore low.

When airplane disturbed and one wing dips the weight act as a pendulum to return the plane back to its original attitude

Question 8

What is a sweepback?

Answer 8

it is a wing in which the leading edge slopes are backwards

Question 9

What happens when there is a disturbance causing the airplane with the sweepback to slip or drop a wing?

Answer 9

low wing presents its leading edge at an angle that is PERPENDICULAR to the relative airflow

Result in lift, rises and the wing restores to its original flight attitude

Question 10

Can sweepback contribute to directional stability?

Answer 10

yes

Question 11

What happens when there is a disturbance that causes one wing to drop in the dihedral?

Answer 11

the unbalance force will produce a sideslip of the downgoing wing but this will cause flow of air into the opposite direction of the slip.

Flow of air will strike the lower wing at a greater angle of attack than upper wing which will roll the plane back into position