Seaplane tender

A seaplane tender is a boat or ship that supports the operation of seaplanes. Some of these vessels, the seaplane carriers could not only carry seaplanes but also provided all the facilities needed for their operation; these ships are regarded by some as the first aircraft carriers and appeared just before the First World War.

In maritime parlance a tender is a vessel that is used to support the operation of other vessels.

In British usage, the term tender was used for small craft, with the term depot ship being used for large sea going vessels. Flying boats and float planes even when based at home in ports and harbour had a need for small support vessels to operate.

British tenders were small craft of launch to pinnace size. These were used to ferry crews, stores and supplies between shore and the aircraft, to maintain the buoys used to mark out "taxiways" and "runways" and to keep these clear of debris to prevent foreign object damage, and in the case of emergency to act as rescue craft and airport crash tenders. All those functions that on land would require wheeled ground support equipment had a need for a watercraft equivalent.

When deploying flying boat squadrons, bases could rapidly be established in areas lacking infrastructure by sending in addition to small craft tenders, flying boat depot ships, these ships could carry out the function of barracks, workshops and control towers, i.e. those functions which in a land based airfield would be fulfilled by buildings.

The first seaplane carrier appeared in 1911 with the French Navy La Foudre, following the invention of the seaplane in 1910 with the French Fabre Hydravion. La Foudre carried float-equipped planes under hangars on the main deck, from where they were lowered on the sea with a crane. La Foudre was further modified in November 1913 with a 10 m (32 ft 10 in)-long flat deck to launch her seaplanes. Another early seaplane carrier was HMS Hermes, an old cruiser converted and commissioned with a flying-off deck in mid-1913. However, HMS Ark Royal was the first ship in history designed and built as a seaplane carrier in 1914.

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