- Flush deck aircraft carriers are those with no island superstructure, so that the top deck of the vessel consists of only an unbroken flight deck.
- "Flush deckers" is a common nickname for a series of American destroyers built in large quantities during or shortly after World War I – the Caldwell, Wickes, and Clemson classes – so called because they lacked the raised forecastle of preceding American destroyers, thus the main deck was a flush deck.
Two different meanings of "flush"
This section possibly contains original research. (October 2014)
"Flush deck" with "flush" in its generic meaning of "even or level; forming an unbroken plane", is sometimes applied to vessels, as in describing yachts lacking a raised pilothouse for instance. "Flush deck aircraft carrier" uses "flush deck" in this generic sense.
"Flush deck" in its more specific maritime-architecture sense denotes (for instance) the flush deck destroyers described above: the flush decks are broken by masts, guns, funnels, and other structures and impediments, and are far from being unbroken planes. "Flush deck" in this sense only signifies that the main deck runs the length of the ship and does not end before the stem (with a separate raised forecastle deck forward) or before the stern (with a separate raised or, as seen on many modern warships, lowered quarterdeck rearward).
This section possibly contains original research. (December 2019)
The British East India Company duplicated the flushed deck design of Bengal rice ships in the 1760s, leading to significant improvements in seaworthiness and navigation for United Kingdom ships during the Industrial Revolution. The flushed deck design was introduced with rice ships built in Bengal Subah, Mughal India (modern Bangladesh), resulting in hulls that were stronger and less prone to leak than the structurally weak hulls of stepped deck design.. This was a key innovation in shipbuilding at the time.
- "Flush Deckers". Destroyer History Foundation. Retrieved October 20, 2014.
- "Technological Dynamism in a Stagnant Sector: Safety at Sea during the Early Industrial Revolution" (PDF).