Aeromodelling

Wing Configurations and Shapes

Aircraft wings are built in many shapes and sizes for difference application. It is depending on the desired flight characteristics of an aircraft. Also, wing designed in difference configurations to achieve greater lift, balance or stability in flight.

Here shows a number of typical wing leading and trailing edge shapes

 

Also figure below shows the common wing forms and configuration.

F-14 Tomcat is a supersonic aircraft with variable geometry wing. This aircraft wing geometry changes according to flying speed by swinging the wings forward and backward.

Enjoy the video

 

Aspect Ratio

Aspect ratio is an indicator of the general performance of an aircraft wing. In aerodynamics, the aspect ratio of a wing is defined as the square of the span divided by the wing area. It is a measure of how long and slender a wing is from tip to tip.

For “high” aspect ratio aircraft wing indicates long, narrow wings, whereas a “low” aspect ratio wing indicates short and stubby. Higher aspect ratio has the effect of a higher rate of lift increase, as angle of attack increases, than lower aspect ratio wings.

High aspect ratio wing – higher Lift Coefficient
lower stalling angle of attack… eg. Gliders

Low aspect ratio wing – lower Lift Coefficient
high stalling angle of attack… eg. Fighter Jets

However because wings may have varied plan forms it is usual to calculate aspect ratio as:

Aspect ratio = wing span² / wing area = Wing span / Chord length

 

Pictures below show the F-15 Eagle with low aspect ratio wing shape and B52 bomber with high aspect ratio wing.

 

Dihedral Angle

The purpose of dihedral is to improve the aircraft stability during flight. Dihedral angle is added to the wings for later or rolls stability. When the aircraft encounters a slight roll displacement caused by distribute from air stream or a gust of wind. An aircraft wings with some dihedral will naturally return to its original position.

The front view of this wing shows that the left and right wing do not lie in the same plane but meet at an angle. The aircraft’s wing is inclined upward an angle from root to tip. The angle that the wing makes with the local horizontal is called the dihedral angle.

You may have noticed that most large airliner wings are designed with dihedral. The wing tips are farther off the ground than the wing root.

 

Anhedral Angle

Highly maneuverable fighter planes, on the other hand do not have dihedral. In fact, some fighter aircraft have the wing tips lower than the roots giving the aircraft a high roll rate. A negative dihedral angle is called anhedral

Wing AnhedralAngle remove the effect of Dutch Roll: Oscillatory motion combining roll & yaw with aircraft waddling from side to side.