What is described as loads carried on a one-time or low-frequency basis?

The term that describes loads carried on a one-time or low-frequency basis is unique sling loads. These loads are specific to particular missions or operations and do not represent standard or regular cargo that is frequently transported. Unique sling loads may include special equipment, vehicles, or items that are necessary for a specific task or situation, making them less common in regular airlift operations.

This distinction is important because understanding the nature of these loads helps in planning and executing operations that require precision and care, given that each unique sling load may also have special handling, rigging, or attachment requirements due to its specific characteristics and mission context. Regular cargo loads and standard cargo loads, in contrast, typically refer to equipment or supplies that are moved regularly, and prohibited loads include items that are not allowed to be transported by air. Therefore, the unique nature of these loads signifies their infrequent occurrence and the need for specialized attention during transport.