Landing gear

Landing gear is the underside of an aircraft or spacecraft that touches the ground when parking, taxiing, taking off, or landing. It keeps the main body of the plane, called the fuselage, safe and above the ground.

Most planes have wheels for landing gear, but some use skids or floats depending on where they fly—such as over water or snowy terrain.

Early airplanes had landing gear that stayed out during flight. Modern aircraft usually have landing gear that folds up inside the body when not needed. This helps planes fly faster and more smoothly.

Landing gear must be very strong to support the weight of the plane and to help when it lands. It is usually arranged with three sets of wheels—one in front and two in back. This design helps keep flights safe.

Specialized companies like Safran Landing Systems, Collins Aerospace, and Héroux-Devtek make landing gear for many different types of aircraft. For spacecraft and rovers, landing gear supports the vehicle after it has landed and while it moves on the surface.

Aircraft

The landing gear is the underside of an aircraft. It is used when the plane is parking, moving on the ground, taking off, or landing. Even though it is a small part of the plane’s weight and cost, it is very important to keep it in good shape. A good wheel can hold a lot and last many years.

There are different ways to set up landing gear. Conventional landing gear, also called "taildragger," has two big wheels near the front and a small wheel at the back. Tricycle landing gear has two big wheels under the wings and a small wheel at the front. Most modern planes use tricycle gear because it is easier to land and take off. Some planes have retractable gear, which folds up into the wings or fuselage to make the plane go faster in the air.

Landing gear has shock absorbers to help when the plane lands. Bigger planes often have many wheels and use thicker runways to hold their weight. Some special planes, like those that land on water, have different gear, such as floats or skis.

Spacecraft

Landing gear is not used on most rockets, because they take off straight up and are not reused. But some special vehicles, like those that land vertically after a short flight or spaceplanes that land like regular airplanes, do have landing gear.

In the 2010s, private companies started making reusable rockets. For example, SpaceX built test rockets with landing gear to practice vertical landings. Their Falcon 9 and Falcon Heavy rockets have special, lightweight landing legs that pop out to touch down safely. The newest rocket being developed, Starship, is planned to have landing legs on both its first and second stages, which would be a first for such vehicles. Spacecraft meant to land on places like the Moon or Mars may also have landing gear, such as legs or air bags, to help them settle safely.