The London-class transport was a type of support vessel used by Starfleet and the Federation in the 24th century. These ships were designed to enter into enemy territory under escort and ferry troops onto enemy planets for ground combat operations. They were also used to transport crews as well as materials to locations outside the Federation where they would be used to build starbases or outposts. This kind of operations meant that the ship was not combat capable and would not survive attacks by enemy warships, which is why it required an escort.