The wingspan (or just span) of an airplane or a bird, is the distance from the left wingtip to the right wingtip. For example, the Boeing 777 has a wingspan of about 60 m (200 feet).
The term wingspan, more technically extent, is also used for other winged animals such as pterosaurs, bats, insects, etc, and other winged aircraft such as ornithopters. For example, a Wandering Albatross (Diomedea exulans) caught in 1965 had a wingspan of 3.63 m, the official record for a living bird.
Wingspan of aircraft
The wingspan of an aircraft is always measured in a straight line, from wingtip to wingtip, independently of wing shape or sweep
Implications for aircraft design
Planes with a longer wingspan are generally more efficient because they suffer less induced drag
and their wingtip vortices
do not affect the wing as much. However, the long wings mean that the plane has a greater moment of inertia
about its longitudinal axis
and therefore cannot roll as quickly and is less maneuverable. Thus, combat aircraft and aerobatic planes usually opt for shorter wingspans to increase maneuverability..
Since the amount of lift that a wing generates is proportional to the area of the wing, planes with short wings must correspondingly have a longer chord. An aircraft's ratio of its wingspan to chord is therefore very important in determining its characteristics, and aerospace engineers call this value the aspect ratio of a wing.
Wingspan of flying animals
To measure the wingspan of a bird, a live or freshly dead specimen is placed flat on its back, the wings are grasped at the wrist
joints,ankles and the distance is measured between the tips of the longest primary feathers
on each wing.
Wingspan in sports
, a fingertip to fingertip measurement is used to determine what is known as a player's wingspan. This is also called reach
in boxing terminology.