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Writer's pictureW. Bonyo

Landing Gear arrangement

The first flight of the Wright Brothers’ Kitty Hawk Flyer, took off from a small track mounted trolley and landed on two skids, it became apparent that for practical purposes aircraft would require wheels for ground operations.


As the aircraft engines improved, these wheels allowed the aircraft to take off without the need for the fixed rail and drop weight, another benefit was in landing.


Overtime, aircraft became adapted to take off and land from different surfaces which gave rise to; Land planes, Seaplanes / Floatplanes /Amphibians.

We are going to look at the different kinds of landing gear orientations employed in aircraft.

The progress in the design of aircraft over the last century had led to the production of faster aircraft that used more powerful engines and carried larger loads.

This has necessitated design requirement of landing gears to be able to:

  • Absorb the landing load and dampen vibration

  • Withstand side loads when landing and taxiing

  • Support the aircraft on the ground

  • Provide minimum friction between the aircraft and the ground

There are two major classifications of the landing gears for the fixed-wing land aircraft: TRI-CYCLE and the CONVENTIONAL/tail-wheel landing gear


Conventional configuration


Originally all aircraft were tail-draggers, for this reason, it came to be known as the conventional landing gear orientation.

This orientation has the two main wheels which are positioned under most of the weight of the aircraft (forward) and a smaller wheel located at the aft end of the fuselage, some had a steel skid plate instead.

The SCHNEIDER showing the convetional landing gear :Photo courtesy of Tangmere Museum

The Tail-wheel gear orientation dominated early periods of aviation and therefore became known as conventional landing gear.


The small tail wheel allows the fuselage to incline, this not only gives clearance for the propellers but also greater clearance between the propeller and loose debris when operating on an unpaved runway.


The major disadvantages of conventional landing gear are: The pilot’s view is restricted by the nose of the aircraft making a large blind spot ahead of him. The dangers of ground looping and the problem of the possibility of the aircraft tipping on to its nose when braking on landing.

Tipped over plane – Alcock and Brown: Photo courtesy Alamy Stock Photo

The tail wheel configuration excels when operating out of unpaved runways the two strong main gear forward provides stability and directional control during the takeoff roll, the lightweight tail wheel keeps the aft end of the fuselage from striking the ground.

Tri-Cycle landing gear configuration

Tri- cycle landing gear: Photo by Joe Jennings via Getty Images

The Tri-cycle gear orientation is the most prevalent landing gear configuration in aviation. It was developed to counter the problems associated with the tail wheel system.

The system had its main gears located behind a shock-absorbing nose wheel. This brings better stability when the plane is on the ground as the center of gravity of the aircraft is forward of the main gear and aft of the nose gear.


Some advantages of this landing gear configuration are: that the tail of the aircraft is suspended off the ground, the pilot has a clear view straight ahead from the cockpit, ground looping is nearly eliminated since the center of gravity follows the directional nose wheel and remains between the main gears.


Light aircraft use tri-cycle gear, as well as heavy aircraft. Twin nose wheels on the single forward strut and massive multi-strut/multi-wheel main gear may be found supporting the world’s largest aircraft, but the basic configuration is still tricycle.

A multi-strut/multi-wheel KQ Aircraft on take off :Photo credits ITN via Getty images by

These landing gear orientation can be classified as either the fixed landing gear or the retractable landing gears.

The FIXED LANDING GEAR system simply as the name suggests remains stationary during flights and when on the ground.

These are found in low powered, low altitude flying and low-speed aircraft.


The more sophisticated RETRACTABLE LANDING GEAR system is found on higher-powered, high altitude aircraft.

These landing gear systems retracts into the fuselage or wings and out of the airstream during the flight to minimize drag and will extend when the plane approaches a landing.

Retractable landing gear schematics: photo courtesy direct science.com



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