The Leaf class is a class of support tanker of the BritishRoyal Fleet Auxiliary (RFA). The class is somewhat unusual as it is an amalgam of various civilian tankers chartered for naval auxiliary use and as such there have been many different designs of ship in this particular class. Leaf names are traditional tanker names in the RFA, and are recycled when charters end and new vessels are acquired. Thus, there have been multiple uses of the same names, confusingly sometimes sharing a common pennant number.
The role of support tanker generally involves the bulk transport of fuel oils between distribution centres, the replenishment of front-line fleet tankers such as the Wave Knight and Fort Victoria classes and using their replenishment at sea (RAS) abilities to allow them to directly support naval warships. For RAS, Leaf-class ships have an amidships derrick allowing a single vessel on either beam and a single point for a vessel astern.