The Sage Type 4 was a prototype British

floatplane A floatplane is a type of seaplane with one or more slender floats mounted under the fuselage to provide buoyancy. By contrast, a flying boat uses its fuselage for buoyancy. Either type of seaplane may also have landing gear suitable for land, ...

of the

First World War World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fig ...

. It was a designed as a two-seat reconnaissance aircraft for the

Royal Naval Air Service The Royal Naval Air Service (RNAS) was the air arm of the Royal Navy, under the direction of the Admiralty's Air Department, and existed formally from 1 July 1914 to 1 April 1918, when it was merged with the British Army's Royal Flying Corps t ...

, but was chosen for service as a floatplane trainer, although the end of the war resulted in production being cancelled.

Design and development

In early 1917, the

Peterborough Peterborough () is a cathedral city in Cambridgeshire, east of England. It is the largest part of the City of Peterborough unitary authority district (which covers a larger area than Peterborough itself). It was part of Northamptonshire until ...

based woodworking company of

Frederick Sage & Company Frederick Sage & Company was a British shop fitting company based in London with an extensive practice in Europe, South Africa, and South America. During both world wars it built and designed aircraft, and after the Second World War it executed mu ...

designed a two-seat patrol

for the

based on Sage's Type 3 landplane trainer. Like the Type 3, the new design, the Sage Type 4, was a single-engined

biplane A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While ...

. Pilot and observer sat in separate tandem cockpits, with the pilot occupying the front cockpit, while the

wireless Wireless communication (or just wireless, when the context allows) is the transfer of information between two or more points without the use of an electrical conductor, optical fiber or other continuous guided medium for the transfer. The mos ...

operator/observer sat in the rear cockpit, with both crew members having good visibility. The aircraft was powered by a single 150 hp (112 kW)

Hispano-Suiza 8 The Hispano-Suiza 8 was a water-cooled V8 SOHC aero engine introduced by Hispano-Suiza in 1914, and was the most commonly used liquid-cooled engine in the aircraft of the Entente Powers during the First World War. The original Hispano-Suiza 8 ...

water-cooled

V-8 engine A V8 engine is an eight-cylinder piston engine in which two banks of four cylinders share a common crankshaft and are arranged in a V configuration. The first V8 engine was produced by the French Antoinette company in 1904, developed and us ...

in the nose driving a

tractor A tractor is an engineering vehicle specifically designed to deliver a high tractive effort (or torque) at slow speeds, for the purposes of hauling a trailer or machinery such as that used in agriculture, mining or construction. Most comm ...

propeller. Undercarriage consisted of two main floats under the wing the a further tail float.Uppendaun 2004, p. 69.''Flight'' 24 July 1919, pp. 974–975. The prototype Sage Type 4a ( serial number ''N.116''Bruce 1957, p. 468.) first flew on 3 July 1917.Bruce 1957, p. 465. The type demonstrated excellent handing during testing, being capable both of flying aerobatic manoeuvres while still being stable enough to be easily flown "hands-off".''Flight'' 24 July 1919, p. 975. Despite this, the type was rejected for service as a patrol aircraft, but it was recommended that it instead be adapted into a float-plane trainer. The aircraft was fitted with dual controls and the engine mounting was modified to allow any one of a variety of 200 hp (149 kW) engines to be fitted. ''N.116'' was converted to the new standard, being fitted with a

Sunbeam Arab The Sunbeam Arab was a British First World War era aero engine. Design and development By 1916 the demand for aero-engines was placing huge demands on manufacturing. To help ease the pressure the War Office standardised on engines of about ; ...

and flew as the Sage Type 4b on 17 May 1918. Sage also designed a revised version, the Sage Type 4c with folding wings of increased wingspan (39 ft in (12.07 m) compared with 34 ft 6 in (10.52 m) for the earlier aircraft and powered by a 200 hp Hispano Suiza engine, with a prototype flying on 12 October 1918.Bruce 1957, p. 466. Both the Type 4b and 4c were adopted as standard training floatplanes for the RNAS, but the end of the First World War resulted in production plans being abandoned.

Variants

;Type 4a :Two-seat patrol seaplane, powered by

Hispano-Suiza 8A The Hispano-Suiza 8 was a water-cooled V8 SOHC aero engine introduced by Hispano-Suiza in 1914, and was the most commonly used liquid-cooled engine in the aircraft of the Entente Powers during the First World War. The original Hispano-Suiza ...

engine. One prototype built. Converted to Type 4b.Bruce 1957, p. 464. ;Type 4b :Two seat floatplane trainer, powered by

engine. Converted from Type 4a.Bruce 1957, p. 465. ;Type 4c :Revised floatplane trainer with folding wings. Powered by Hispano-Suiza 8B engine. One example built.Bruce 1957, p. 466.

Specifications (Sage 4c)

Notes

References

Bibliography

*Bruce, J.M. ''British Aeroplanes 1914-18''. London:Putnam, 1957. *Goodall, Michael H. ''The Norman Thompson File''. Tunbridge Wells, Kent, UK: Air Britain (Historians) Ltd, 1995. .
"Milestones" The Sage Machines
. ''

Flight Flight or flying is the process by which an object moves through a space without contacting any planetary surface, either within an atmosphere (i.e. air flight or aviation) or through the vacuum of outer space (i.e. spaceflight). This can b ...

'', 24 July 1919. pp. 971–975. *Uppendaun, Bob. "Sage-Like Thoughts:The Products of Frederick Sage & Co". ''

Air Enthusiast ''Air Enthusiast'' was a British, bi-monthly, aviation magazine, published by the Key Publishing group. Initially begun in 1974 as ''Air Enthusiast Quarterly'', the magazine was conceived as a historical adjunct to ''Air International ' ...