While its lack of onboard battery would limit travel to daylight hours, and its speed will only be approximately half that of a Boeing 747, the Varialift airship does promise to be a useful cargo carrier. Its creators claim that it will be able to carry loads ranging from 50 to 250 tons. Larger models with payloads up to 3,000 tons aren't out of the question either. Bulky cargo such as electricity pylons, wind turbine blades, and towers, or even prefabricated structures such as oil rigs could be carried underneath using cables. That means that cargo will have a weight limit, but no practical size limit.