ISO 21100:2020 specifies the minimum requirements for airworthiness approval of air cargo pallets, nets and containers, generally designated as air cargo unit load devices (ULD).

This document is intended to provide a uniform technical reference for air cargo unit load devices approval. As a prerequisite, it is presupposed that the applicable general civil aviation requirements and the aircraft manufacturer's approved Weight and Balance Manual are followed.

This document defines the minimum performance requirements and test parameters for air cargo unit load devices requiring approval of airworthiness for installation in an approved aircraft cargo compartment and restraint system that complies with the cargo restraint and occupant protection requirements of EASA CS-25 or 14 CFR Part 25, except for the 9,0 g forward ultimate inertia force of ° 25.561(b) (3) (ii).

This document applies to airworthiness approved air cargo unit load devices intended for carriage on board civil transport category airplanes type certificated under EASA CS-25 or 14 CFR Part 25, or equivalent.

This document exclusively applies to unit load devices airworthiness approval and testing parameters. It does not apply to aircraft design or aircraft operating requirements, which are provided by the approved Weight and Balance Manual for each aircraft type.

Other aspects that do not directly pertain to air cargo unit load devices airworthiness approval and testing are not covered by this document and are defined in other International Standards (see Bibliography), e.g.:

— ULD design specifications,

— ULD in service damage limits,

— ULD restraint malfunction limitations,

— ULD test methods,

— ULD load distribution models,

— ULD maximum allowable contours,

— ULD CG (centre for gravity) location control means,

— ULD pressure equalization methods,

— ULD utilization guidelines.

Air cargo unit load devices qualified prior to publication of this document were approved in accordance with the requirements of ISO 8097:2001. This document is intended as a TSO approval reference for all new models of unit load devices in the sizes and types it covers, in replacement of ISO 8097. For air cargo unit load devices the size or type of which is not covered in this document, see the requirements of ISO 8097:2001, if their size or type is contained therein, or other equivalent criteria, if not.

NOTE 1 ISO 8097 is based on USA National Aerospace Standard NAS 3610 revision 10:1990, Specification for Cargo Unit Load Devices.

NOTE 2 The requirements for cargo covers are not defined in this document, except insofar as net restraint is incorporated therein.