BS ISO 20291-1. Air cargo. Restraint slings Part 1. Design and testing
|Standard number:||20/30361410 DC|
|Status:||Draft for Comment|
- 55.180.30 Air mode containers, pallets and nets
This document specifies the design criteria and testing methods adequate to guarantee the ultimate strength and operational dependability of cargo restraint sling assemblies made of steel wire rope, with a 22,25 kN (5 000 lbf) rated ultimate load capability, as can be used by the airline industry in order to restrain on board civil transport aircraft during flight:
cargo loaded and tied down onto airworthiness approved air cargo pallets, themselves restrained into aircraft lower deck, main deck or upper deck cargo systems and meeting the requirements of ISO 8097 (NAS 3610) or ISO 21100, or
non unitized individual pieces of cargo, or pieces of cargo placed onto an unrestrained ("floating") pallet into either lower deck, main deck or upper deck containerized cargo compartments of an aircraft, to be restrained onto aircraft structure attachment (tie-down) points.
2 (two) types of wire rope restraint slings are defined:
type A: adjustable length restraint sling assemblies, including a tension retaining device and termination fittings attached to the wire rope end eyes.
type B: fixed length restraint sling extensions, to be used in conjunction with a type A cable. Extensions are usually terminated at both ends by eyes, without additional fittings, and can be attached through hooks or shackles.
Cable assemblies made of steel wire rope are intended to be used in lieu of cargo restraint straps meeting the requirements of ISO 16049-1, where straps inherent elongation under tension appears unadvisable for a given tie-down arrangement. Typical examples of loads where substitution of cables for straps throughout a given tie-down arrangement can be advisable are those for which even limited movement during flight could be hazardous, such as: heavy vehicles, aircraft engine stands, helicopters, machinery, etc...
The cables specified in this document are intended exclusively for restraint purposes on board aircraft, and not for use as lifting slings.
On the date of publication of this document, no airworthiness approval procedure by Civil Aviation Authorities is applicable to restraint slings. Their use for cargo restraint, however, remains subject to the requirements of the approved aircraft type or sub-type Weight and Balance Manual: see ISO 20291-2.