This is an example of a tricycle landing gear that is found in newer aircraft models. This type of landing gear makes the aircraft easy to steer because the nose gear is steerable.
Conventional fixed landing gear consists of two wheels forward of the aircraft's center of gravity and a small tail wheel located in the rear. This configuration is nicknamed the "taildragger."
The AV-8 Harrier has a tandem landing gear.
Landing gear is the structure under a plane's fuselage that allows it to land safely. The earliest landing gear consisted of skids, but designers soon attached wheels to the skids. Landing gear must have some mechanism for absorbing the force of the landing in addition to the airplane's weight. Early gear used flexible material for landing gear struts (the structure that connected the airframe and the wheels). Some landing gear use a shock absorbing system called the oleo strut that cushions the landing and keeps the plane level while landing.
There are several types of landing gear: Conventional landing gear consists of two wheels forward of the aircraft's center of gravity and a third, smaller wheel at the tail. This small wheel can turn in any direction. This configuration has the nickname the "taildragger" because, when the plane is on the ground, the tail of the plane is closer to the ground than the forward end.
Tricycle landing gear consists of a forward (nose) wheel and a pair of wheels located midway on the fuselage. The nose gear is steerable by means of the rudder pedals.
Tandem landing gear (also called bicycle landing gear) consists of a main gear of two sets of wheels set one behind the other.
Landing gear can be either fixed or retractable. Often, smaller, less expensive planes have fixed landing gear-landing gear that remains exposed when the plane is flying--because it is less costly to build and maintain. Retractable landing gear can be retracted into the body of the plane. This feature gets the structure out of the airflow and reduces drag.
Aircraft that have to land on water are fitted with pontoons rather than wheels. Some planes had interchangeable pontoons and wheels so that the plane could be used to land both on land and on water.