Designed by Supermarine to accommodate up to four passengers, the company produced a series of interchangeable interiors that could be used at short notice, which enabled the Channel to be used as a fighter or for training purposes.

In 1921 the Imperial Japanese Navy Air Service acquired three Channel II flying boats which were shipped out with the British-led Sempill Mission to Japan.

With the intention of beginning regular air flights over short-haul sea routes across the English Channel, Supermarine purchased ten AD Flying Boats that during the war had been kept in storage by the military after their construction.

[5][6] Attention was paid towards the comfort of the passengers, who were provided with compartments that could be either closed over or left open (with a windscreen included to protect them from the wind and spray), and seats that were kept clean by being designed to spring up when not in use.

[7] In October 1920, the aeronautical magazine Flight described the aircraft as able “to delight the heart of any sea-faring man, for they are pre-eminently the product of men who know and understand the sea and its ways”.

[3] The new service was used in a variety of different ways: ferry passengers who had missed their boat to the Isle of Wight could embark from Bournemouth Pier for the flight across the Solent; and spectators attending the Cowes Regatta had the opportunity to view the yachting from the air in a Channel.

Several aircraft were delivered to the company, including three Avro 504 sea planes and three Channel I flying boats; and hangars and a slipway were built at Hinson's Island.

[24][25] The expedition team, led by Cochran Patrick, included two pilots, three mechanics and four photographers, surveyed the numerous unmapped small streams and mangrove swamps, a task that was considered to be near impossible without the use of aircraft.

[27] The delegation was impressed enough by the aircraft's performance for three Channel II flying boats to be acquired by the Japanese and shipped out with the British-led Sempill Mission to Japan.