This SAE Aerospace Recommended Practice (ARP) defines minimum requirements for an aircraft transport ULD to transport horses properly and safely by air, to protect the horse(s) from injuries and to protect the aircraft from corrosion created by waste spill. The ULD is designed to accommodate one horse or several. There are two types of ULDs for aircraft transportation of horses:

1. a Type 1: The ULD is an airworthiness certified structural container, satisfying the requirements of NAS 3610 for the appropriate base size.
2. b Type 2: The ULD consists of a self-contained stall which is positioned on a standard aircraft pallet and restrained to the pallet by means of a cargo pallet net or by straps.