Airport foldable and fragile pole application scope: The supporting structures of all auxiliary navigation equipment in the runway obstacle restriction area.
Fragile and brittle items — may break (shatter), bend, or yield under specified impact forces, thus becoming less harmful lightweight objects to aircraft.
Fragility
Various visual and non-visual navigation facilities at airports (such as approach lighting towers, meteorological equipment, and radio navigation equipment) are typically located near runways, taxiways, and aprons. If an aircraft in takeoff or landing ground operations were to collide with them unexpectedly, it could pose a danger. All such equipment and their supports must be collapsible and installed as low as possible to ensure that collisions do not lead to aircraft control loss. Collapsibility can be achieved through various design concepts, such as using lightweight, brittle, and low-toughness materials, components, and fasteners, to ensure that collapsible objects break, bend, or yield upon impact.
Flexible and fragile poles (hereinafter referred to as "flexible poles") are support structures made in single-pole, tower-type, and other configurations, utilizing lightweight fragile materials and fragile structures.
Flexibility Condition for Air-Craft Easy-Bendable and Fragile Rod
For aircraft components that may not withstand a collision with a falling aircraft, the breakable rods must be easily broken and shattered upon impact by an aircraft weighing 3,000 kg and traveling at 140 km/h. For components that may not slide on the ground upon collision, the breakable rods must also be easily broken and shattered upon impact by an aircraft weighing 3,000 kg and traveling at 50 km/h. The force exerted by the breakable rod on the aircraft during a collision should not exceed 45 KN; the energy transferred to the aircraft by the breakable rod should not exceed 55 KJ.