The Supermarine Channel (originally the Supermarine Channel Type) was a modified version of the AD Flying Boat, purchased by Supermarine from the British Air Ministry and modified for the civil market with the intention of beginning regular air flights across the English Channel. The aircraft were given airworthiness certificates in July 1919. The Mark I version, later called the Channel I, was powered with a Beardmore engine; a variant designated as Channel II was fitted with a Armstrong Siddeley Puma engine. 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.
The Channel was first used from August 1919, when it flew passengers across the Solent and to the Isle of Wight. Norway's first airline Det Norske Luftfartsreder A/S of Christiania purchased three of the aircraft in 1920, and four aircraft were ordered for the Norwegian Armed Forces, which began operating from May that year. A Channel was used by the New Zealand Flying School, and Channel II aircraft were sent to Bermuda as part of a project to promote aviation in the region and transported to Venezuela to be used to undertake the survey for oil at the delta of the Orinoco. 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.
Design and development
The ban on commercial flights in the United Kingdom imposed during World War I was lifted in May 1919. 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. The AD Flying Boat was designed in 1915 by the British yacht designer Linton Hope.
After acquiring the AD Flying Boats, Supermarine modified them for the civil market, before being given airworthiness certificates in July 1919. The aircraft was redesigned to accommodate up to four passengers, although limited to three if amphibian landing gear was fitted. the modified aircraft were rebranded as the Supermarine Channel Type, with the name 'Channel' first appearing on 2 April 1920. 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.
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”. The Channel's engine was a Beardmore 160 hp, separated from the wing structure and fixed at the top of an A-shaped frame to prevent vibrations from passing to the wings. Because of the position of the engine, the tail unit was made with two planes. The Channel was equipped with an anchor and a boathook. Mitchell's team produced a series of interchangeable interiors that could be used at short notice, enabling it to be used as a fighter or for training purposes.
The Supermarine Commercial Amphibian, a passenger-carrying flying boat that was the first aircraft to be designed by Mitchell, was based on the Supermarine Channel. It was built at the company's works at Woolston, Southampton for an Air Ministry competition that took place during September 1920.
Operational history
England
The new civilian air services from the Port of Southampton to Bournemouth and to the Isle of Wight began in early August 1919. Of the ten Channels, five were put to regular use, whilst the others were held in reserve, so allowing plenty of time for maintenance work to be done on them all.
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. During the British railway strike of 1919, Channels were used to deliver newspapers around the south coast. On 28 September 1919, Supermarine operated the first international flying boat service, when Channel I aircraft for a short period carried paying passengers from Woolston to Le Havre, replacing the steam packets that had stopped operating in support of the railway strike. Supermarine suspended flights to the Isle of Wight during the winter months, and whenever poor weather conditions occurred.