Bungee Shock Absorbers
When you drive your automobile over pot holes and poorly maintained roads the shock absorbers protect your auto from damage and give you a rather smooth ride. Airplanes have similar effects from ruts or bumps in unimproved runways as well as takeoff and landing on grass surfaces. The American Eagle is equipped with a system on its landing gear that provides a way to operate under the above conditions. It is referred to as a “bungee cord” or “shock cord” system to absorb landing gear shock so that it is not transmitted back into the aircraft structure and does serious structural damage.
Bungee cords have been used to provide lightweight suspension for aircraft landing gear since the very early days of aviation. The big advantage of these systems is that they save weight as compared with other more sophisticated systems in use.
The bungee cord shock absorber consists of an elastic cord of one or more elastic strands that are formed into the main core of the shock cord. The elastic cord is generally covered with a woven cotton or polypropylene covering. As the aircraft landing gear is subjected to the jolts of takeoff and landing the elastic cord is stretched allowing the landing gear mechanism to pivot and move absorbing the force. As the force is absorbed the elastic cord(s) return the landing gear assembly to its original configuration.
Other types of landing gear shock absorbers are in use on other aircraft, but the Eagle uses this particular system.