Unclaimed Baggage
Baggage that arrives at an airport on a flight and is not picked up or claimed by a passenger or crew member.
Unidentified Baggage
Baggage at an airport, with or without a baggage tag, which has not been picked up by or identified with a passenger or crew member.

Unit Load Device (ULD)
Any type of freight container, aircraft container or aircraft pallet with a net that is capable of being locked into the aircraft cargo restraint system.
A ULD may or may not be certified by government airworthiness authorities.
Certified ULD – considered as a removable aircraft hold, structurally capable of fully restraining the load contained within and/or providing adequate protection to the aircraft systems and structure.
Non-certified ULD – not considered as a removable aircraft hold, can only be loaded into aircraft holds that are compartment restraint certified and pursuant to the instructions of the aircraft manufacturer's weight and balance manual designated to that aircraft. For containers, the base plate must be structurally attached to and an integral part of the assembly, and the ULD must be capable of fully containing or restraining the cargo or baggage contained within.
Note: An overpack is not included in this definition. Unknown Cargo
A consignment of cargo tendered to a regulated agent or operator that has not been submitted to appropriate security controls, or
A consignment of cargo subjected to appropriate security controls that may have or is confirmed to have been subjected to unlawful interference.
See Cargo.

Unlawful Interference
Any act or attempted act that may jeopardise the safety and security of international civil aviation, to include:
ƒ unlawful seizure of an aircraft in flight or on the ground;
ƒ hostage-taking on board an aircraft or at an airport;
ƒ forcible intrusion on board an aircraft, at an airport or on the premises of a related civil aviation facility;