The structure on the modern naval amphibious ships does not exactly fit the traditional "
well deck" definition of a weather, or open deck, that is lower than adjacent decks, surrounded by bulkheads that would, lacking proper drainage, form a catchment for water; however, the structure has its origins in such an exaggerated deep deck on World War II-era
tank landing craft (TLC) the British forces were considering. On July 19, 1941, Major R. E. Holloway, Royal Engineers, forwarded a design from a 1924 patent by Otto Popper of the
Danube International Commission concerning a barge transporter for
Danube barges. That evolved into the British TLC-C that would become the Dock Landing Ship (LSD) that had an open, very deep and special-purpose well deck open to the elements and thus technically a "well deck" in the traditional definition. The open well deck began to see covering in part with platforms, particularly helicopter landing platforms, and in most modern form is no longer a weather deck, being completely enclosed overhead. The structure is seen in ships with a substantial air assault role such as the . The term "well deck" is still used for the newer structure in the U.S. Navy, that more clearly separates traditional usage from modern naval function. == Non-military application ==