This SAE Aerospace Recommended Practice (ARP) applies to landing gear structures and mechanisms (excluding wheels, tires, and brakes and other landing gear systems) for all types and models of civil and military aircraft. All axles, wheel forks, links, arms, mechanical and gas/oil energy absorbers, downlock and uplock assemblies, braces, trunnion beams, and truck beams etc., that sustain loads originating at the ground, and that are not integral parts of the airframe structure, should be designed and validated in accordance with this document. Hydraulic actuators (retraction, main and nose gear steering, positioning, damping, etc.) should also be included in this coverage. System level, non structural components such as retraction/extension valves, controllers, secondary structure and mechanisms in the airframe (e.g. manual release mechansims, slaved doors) as well as equipment that is located in the cockpit is not addressed in this ARP.