Airport Folding and Fragile Poles

Airport foldable and fragile pole application scope: Support structures for all auxiliary navigation equipment in the runway obstacle limitation surface.
Fragile and brittle items — objects that will break (shatter), bend, or yield under specified impact forces, thereby reducing the hazard to aircraft from lighter-weight objects.
Crimp resistance
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 in takeoff or landing ground operations were to collide with them unexpectedly, it could pose a hazard. 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, easily collapsible, and brittle materials, components, and fasteners with low toughness, to ensure that collapsible objects break, bend, or yield upon impact.
Flexible and fragile poles (hereinafter referred to as "flexible poles") are support structures of single-pole, tower, and other configurations made from lightweight, fragile materials and flexible structures.
Fragility and Breakage Conditions of Airline Easy-Fold and Fragile Poles
For aircraft components with potential for in-flight or ground collision with a folding shaft, the shaft must be susceptible to bending and fracturing upon impact by an aircraft weighing 3,000 kg and traveling at 140 km/h. For aircraft components with potential for ground collision but not ground sliding with a folding shaft, the shaft must be susceptible to bending and fracturing upon impact by an aircraft weighing 3,000 kg and traveling at 50 km/h. The force exerted by the folding shaft on the aircraft during impact should not exceed 45 KN; the energy transferred to the aircraft by the folding shaft should not exceed 55 KJ.