ISO 21785-2020 pdf free.Air cargo unit load devices — Loaddistribution model.
1.Scope:This document defines the industry agreed model for load distribution on air cargo unit load devices(ULD) bases to apply the maximum allowable centre of gravity (C.G.) eccentricity.lts purpose is to establish a common reference load distribution algorithm for:
a) comparable and repeatable ULD testing methods, or equivalent numeric simulations;
b) aircraft structure and cargo systems design assumptions,consistent with existing airframers practices; and
c) definition of operators unit load devices utilization rules and cargo build-up training programs.lt applies to all types of unit load devices intended for use on board civil transport aircraft andairworthiness approved in accordance with the performance requirements and testing parameters ofeither IS0 21100 or, as applicable, ISO 8097.
lt also applies to non-airworthiness approved (non-certified) containers as defined in ISO 4118,the utilisation of which is controlled by the provisions of the aircraft type’s Weight and Balance Manualand other airframe manufacturer’s documents.
2.Normative references:The following documents are referred to in the text in such a way that some or all of their contentconstitutes requirements of this document. For dated references,only the edition cited applies.Forundated references, the latest edition of the referenced document (including any amendments) applies.
3.Principle
3.1.1 Airworthiness approval of each type and size of unit load device includes maximum load centreof gravity (C.G.) eccentricity (offset) allowances at unit maximum gross mass, that are part of its testingand approval (see ISO 21100 or ISO 8097 , as applicable, for unit load device configurations and ultimateload criteria).
3.1.2 C.G.eccentricity is expressed and measured in percentage (%) of the ULD’s base length or widthfrom the geometric centre of the base.The maximum eccentricity shall be demonstrated under maximumgross mass in accordance with IS0 21100 or ISO 8097 , therefore allowed by ULD approval, is ±10 % ofbase length and width, or 5 % of length and10 idth for sizes G, H, J, and R ULDs.
3.1.3 The load distribution on a pallet’s surface or a container base corresponding to the certifiedmaximum C.G. eccentricity allowances shall be defined as homogeneous cargo with maximum grossmass occupying a correspondingly reduced area of the base surface.See example (for 10 % simultaneouslongitudinal and lateral C.G.offset) in Figure 1.ISO 21785 pdf download.