Wing Span and Flight
Country: United States
Date: December 2006
How does the wing span effect the flight of the plane?
I have two thoughts that might help answer your question. Although
the wing span itself does not directly affect the flight of the
aircraft, it is part of a more complex story.
There is a concept called aspect ratio. To calculate the aspect
ratio, you divide the wing span by the chord of the wing. The chord
is the distance from the leading edge to the tailing edge. A high
aspect ration is found on wings that are good at gliding. Pilots
call it a good "L over D" (written L/D). Have you seen gliders with
long thin wings? These have high aspect ratios and can glide a long
distance for their height above the ground. Power planes do not need
a high aspect ration because they have engines and do not have to
depend on their ability to glide. If you know what a delta wing
is... it has a very low aspect ration and does not glide very well at all.
A second way to address your question... if you multiply the span
times the chord you will get the area of the wing. When you divide
the weight of the aircraft by the area of the wing, you get the "wing loading."
Weight / wing area = wing loading
One of the chrematistics of an airplane is its stall speed. The
speed at which the aircraft can no longer maintain level
flight. The stall speed increases as the wing loading
increases. Looking at it in another way, the greater area of the
wing (bigger wing span and/or bigger chord) the more weigh the
aircraft can bear without having a problem with stall speed.
A last thought... one of the limiting factors in having a large wing
span is the problem of making a long wing strong. In recent years
we have developed new materials (like carbon fiber technology) which
makes long wing spans easier to construct.
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Update: June 2012