Unit Load Device

Unit Load Devices, or ULDs, are pallets and containers used to load luggage, freight, and mail on wide-body aircraft and specific narrow-body aircraft. They allow large quantities of cargo to be bundled into large units. Since this leads to fewer units to load, it saves ground crews time and effort, and helps prevent delayed flights. Each ULD is manifested separately so that its contents can be tracked.
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Any type of freight container, aircraft container, aircraft pallet with a net, or aircraft pallet with a net over an igloo. (49CFR171)