The Bristol Grampus was a British

prototype A prototype is an early sample, model, or release of a product built to test a concept or process. It is a term used in a variety of contexts, including semantics, design, electronics, and software programming. A prototype is generally used to ...

biplane

passenger aircraft An airliner is a type of aircraft for transporting passengers and air cargo. Such aircraft are most often operated by airlines. Although the definition of an airliner can vary from country to country, an airliner is typically defined as an ai ...

proposed by the

British and Colonial Aeroplane Company The Bristol Aeroplane Company, originally the British and Colonial Aeroplane Company, was both one of the first and one of the most important British aviation companies, designing and manufacturing both airframes and aircraft engines. Notable a ...

but not built.

Design and development

Following the end of the First World War, the

looked at producing a general-purpose passenger or cargo aircraft.

Frank Barnwell Captain Frank Sowter Barnwell OBE AFC FRAeS BSc (23 November 1880 – 2 August 1938) was a Scottish aeronautical engineer. With his elder brother Harold, he built the first successful powered aircraft made in Scotland and later went on to a c ...

proposed a single-engined biplane for six passengers, powered by a

Siddeley Tiger The Siddeley Tiger was an unsuccessful British aero engine developed shortly after the end of World War I by Siddeley-Deasy. Problems encountered during flight testing caused the project to be cancelled. Design and development Developed usi ...

engine and named Grampus I. The directors of the company thought it too large for the proposed market and were concerned about the supply of Tiger engines. Barnwell returned with a smaller three-passenger Grampus II powered initially by a RAF 4a air-cooled engine which would be replaced by the Siddeley Lynx radial engine on production aircraft. The directors did not approve of the design, nor of two eight-passenger variants also proposed. In February 1920 the project was abandoned as none of the designs appeared to meet the criteria for an

Air Ministry The Air Ministry was a department of the Government of the United Kingdom with the responsibility of managing the affairs of the Royal Air Force, that existed from 1918 to 1964. It was under the political authority of the Secretary of Stat ...

competition.

Variants

;Type 31 Grampus I :Proposed six-passenger variant powered by a

engine, not built. ;Type 42 Grampus II :Proposed three-passenger variant powered by a RAF 4a engine, not built. ;Type 43 Grampus IV :Proposed eight-passenger variant powered by four

Lucifer Lucifer is one of various figures in folklore associated with the planet Venus. The entity's name was subsequently absorbed into Christianity as a name for the devil. Modern scholarship generally translates the term in the relevant Bible passa ...

engines, not built. ;Type 57 Grampus V :Proposed variant of the Grampus IV for the American market with two

Hall-Scott Hall-Scott Motor Car Company was an American manufacturing company based in Berkeley, California. It was among the most significant builders of water-cooled aircraft engines before World War I. History 1910–21 The company was founded in 1910 ...

engines, not built.

References

;Notes ;Bibliography * {{Bristol aircraft Grampus 1920s British airliners