Airport foldable and fragile pole application scope: The supporting structures of all aids to navigation equipment within the runway obstruction area.
Fragile and brittle items — objects that may break (shatter), bend, or yield under specified impact forces, thereby posing a reduced risk to aircraft as lightweight objects.
Crip proneness
Various visual and non-visual navigation facilities at airports (such as approach lighting towers, meteorological equipment, radio navigation equipment, etc.) are generally located near runways, taxiways, and aprons. If an aircraft taking off or landing collides with them unintentionally, it could pose a danger. All such equipment and their supports must be breakaway and installed as low as possible to ensure that collisions do not lead to aircraft control loss. Breakaway properties can be achieved through various design concepts, such as using lightweight, breakable, and brittle materials, components, and connectors, to ensure that breakaway objects shatter, bend, or yield upon impact.
Flexible and fragile poles (hereinafter referred to as "flexible poles") are support structures made in single-pole, tower frame, and other configurations, utilizing lightweight, fragile materials and a design prone to bending.
Condition for bendability of aviation easily breakable and fragile rods
For aircraft parts susceptible to collision with other aircraft that may not take off or land safely, the bendable rods must be easily bendable and breakable upon impact by an aircraft weighing 3,000 kg and traveling at 140 km/h. For aircraft parts susceptible to collision with other aircraft that may not glide on the ground, the bendable rods must be easily bendable and breakable upon impact by an aircraft weighing 3,000 kg and traveling at 50 km/h. The force exerted by the bendable rod on the aircraft during impact should not exceed 45 KN; the energy transferred to the aircraft by the bendable rod should not exceed 55 KJ.