C.Barnes Short Aircraft since 1900 (Putnam)
Short Tractor Biplanes (1910-12)
The next line of experiment was the S.47 Triple-Tractor with two separate 50 hp Gnomes mounted in tandem in a tractor fuselage extended forward, with the front engine driving a direct-coupled airscrew and the rear engine, facing backwards so as to rotate the opposite way, driving wing-mounted, counter-rotating airscrews through Wright-type chain gears; the Triple-Tractor had a single cockpit with two seats side-by-side. Frank McClean flew S.47 for the first time on 24 July, 1912, and Lieut C. J. L’Estrange Malone flew its official acceptance tests on 22 August, when it received serial T4. It performed well apart from its propensity for generating heat under its 16 ft long cowling, which earned it the soubriquet of Field Kitchen. It was used for a variety of experiments, including the early trials of the first Rouzet wireless transmitter, whose signals were picked up at a range of 30 miles.
S.47 Triple-Tractor - Span 48 ft (14-6 m); length 41 ft (12-5 m); area 500 sq ft (46-5 tn2); weights not recorded; speed 60 mph (96-6 km/h).
M.Goodall, A.Tagg British Aircraft before the Great War (Schiffer)
Deleted by request of (c)Schiffer Publishing
S47. Triple tractor biplane, 'The Field Kitchen''
This development based on earlier tractor biplanes was a twin-engined machine with both engines contained in an extended fuselage under a long cowling. The rear engine was turned round and drove, by chains, the twin propellers mounted on the inboard interplane struts. This engine rotated in the reverse direction to the normally mounted front engine with directly driven propeller. The rear engine was inadequately cooled and the severe heat generated caused the use of the nickname. The crew of two were seated side-by-side.
McClean tested S47 for the first flight on 24 July 1912, and it was soon taken over by the Navy, becoming T4 later No.4. It was used for experiments with wireless transmission but was not repaired after damage on 22 January 1913.
Power: Two 50hp Gnome seven-cylinder air-cooled rotaries. The front engine drove a propeller direct, the rear rotating in the opposite direction drove twin propellers by chains.
Area 500 sq. ft
Speed 60 mph
S53. Twin tractor biplane
This was to be a machine for McClean with two 70hp Gnome engines which was not built.
P.Lewis British Aircraft 1809-1914 (Putnam)
Short S.47/T.4 Triple Tractor
The Triple Tractor biplane of 1912 was another Short Brothers' experiment in multi-engine lay-out. The machine was basically an S.41 with an extended cowling 16 ft. in length, under which were concealed two 50 h.p. Gnome engines. The front one drove a direct-coupled tractor propeller, while the rear was connected by chains to a tractor propeller mounted mid-way between the wings on each side of the fuselage. The engines were fitted in tandem in the fuselage, while the pilot and passenger had side-by-side seats in the cockpit. The Triple Tractor was flown during July, 1912, but so much heat was generated under the cowling that it became known as the "Field Kitchen". Span, 48 ft. Length, 41 ft.