Introduction to Landing Gear

What Is Landing Gear?

Generally when you heard the word landing gear, the first thing that might hit your mind may look like this,

Or this.

You are absolutely correct, it is what is called landing gear but it’s not just it; there are few more that are also included in landing gear category.?

You might wonder what else could fit in the definition of landing gear, for your surprise look at these beauties.

Technically landing gear refers to the retractable or non-retractable system of components installed on an aircraft that supports the aircraft when it is on the ground, facilitates smooth takeoffs and landings, and assists in taxiing or moving on the ground.

The landing gear is a critical part of an aircraft's structure and plays a key role in ensuring flight safety by supporting the aircraft's weight, reducing landing impact forces, and aiding directional control during taxiing and landing procedures.

Aircraft landing gear supports the entire weight of an aircraft during landing and ground operations. They are attached to primary structural members of the aircraft.

To define the non-conventional types of landing gear, the definition of Landing gear may be altered to the following,

“Landing gear refers to the retractable or non-retractable system of components installed on an aircraft that supports the aircraft when it is on the ground, water and snow/ice, facilitates smooth takeoffs and landings, and assists in taxiing or moving on the ground, water and snow/ice.

?To understand further about the configurations of landing gears I had segregated them as per terrain, arctic or ocean that they lands in.

Landing on land/ground

The most common place where an aircraft would be landing in will be a strip of land, paved, unpaved or sandy. In either of them aircrafts landing gear would have wheels to support smooth landing.?

You would have seen aircraft landing over paved concrete solid runways like these:

Wheel Landing Gear

Globally we have airports with runways to provide aircrafts with ideal place to lands in but in some remote regions of planet we don’t have that facility and to counter act that deficiency our aeronautical experts have developed landing gears that are able to land in almost anywhere.

Aircraft with modified landing gear or purposely built aircrafts for dirt landing are able to land almost any plain ground as per their design capacity.

Now for example this C130 Hercules can land on a dirt strip with a long run to achieve the required velocity to take off.

But these relatively smaller aircraft mostly used for chartered or private service powered by turboprop or turbofan/jet engines acquire take off velocity much earlier compare to C-130 resulting in ability to utilize smaller runways.

? Where these single piston engine aircrafts can take off and land from a ground as long as couple of meters.

Landing on Water

You may have seen it movies, an aircraft landing or taking off from an ocean or any other water body. They are called “seaplanes”.

Seaplanes

As its name says it all, a plane that operates from water is known as Seaplane. What make it possible? Now that’s a question.

We have seen boats and massive ships floating over ocean, it’s quite fascinating to see a human being struggling to stay up on water surface while the boat with 100 times more mass then a human floats above. Ever wonder how they don’t sink in water with such big mass?

Well this guy did wonder,

He is “Archimedes of Syracuse”, according to Wikipedia he was an Ancient Greek mathematician, physicist, engineer, astronomer, and inventor from the ancient city of Syracuse in Sicily.

He finds that “The net upward force on an object immersed in water is equal to the weight of the water displaced by the object.”

The upward force acting upon the body is buoyancy, which help a boat float. Similarly seaplanes have floats or pontoons attached to its landing gear which help them float.

Floats or pontoons are airtight hollow structures, similar to pressure vessels, designed to provide buoyancy in water. Floats can be attached as landing gear or to fuselage.

Seaplanes with floats or pontoons on belly also have small floats or pontoons attached to their wing to maintain stability over water.

Seaplanes are not limited to oceans. Mostly seaplanes are Amphibious, which means that they can land and takeoff from water but also can operate from normal runway. They also have wheels which make possible for them to land on a runway.

For the mater of reliability seaplane are in service since 1912, which proves it reliability to be perfect for operation as flying boats.

Landing on Snow/ice

Landing on snow or ice is somehow similar to landing on water, except you have more vicious material then water and less friction in case of ice bed.

Similar to water, to avoid sinking in snow it is necessary to increase the contact area of landing gear with snow. To achieve this mostly aircraft operating from snowy area, frozen lake or from arctic have ski landing rather than conventional landing gear. This is way they are called Ski planes.

Considering the weather, in some regions it’s not snow or frozen lakes all along the year but for few months or weeks. In such situations they install skies over conventional landing gears.

And it’s not just small aircrafts that land on snow, narrow and wide body aircraft also land and takeoff from snow and ice.

Recently Boing 787 and Airbus A340 had successfully landed on Ice bed of Antarctica.

Landing gear expands far beyond the conventional image of wheel touching the tarmac. From solidity of land to fluidity of water and unpredictable nature of ice and snow landing gear encompasses adoption for varied terrain.

Seaplane and ski planes or the innovative integration of floats/pontoons not only demonstrate the human ingenuity but the fundamental principles of physics.

From vast ocean to snow covered landscape, landing gear is not just a technicality but a bridge between sky and the diverse surface of earth.