O.Thetford, P.Gray German Aircraft of the First World War (Putnam)
Friedrichshafen FF 35
Built in February 1915, the FF 35 was intended as a torpedo carrier, but only a single machine (No. 300) was constructed. The twin 160 h.p. Mercedes D III engines drove pusher airscrews. Span, 23.74 m. (77 ft. 10 3/4 in.). Length, 13.5 m. (44 ft. 3 5/8 in.). Area, 100 sq.m. (1,080 sq.ft.). Weights: Empty, 2,292 kg. (5,042 lb.). Loaded, 3,543 kg. (7,795 lb.). Speed, 114 km.hr. (71.25 m.p.h.). Armament, torpedo and one or two manually operated Parabellum machine-guns.
Flight, October 16, 1919.
SOME FRIEDRICHSHAFEN "MILESTONES"
Figs. 17 and 18 show
"the F.F. 35
which was fitted with two Mercedes engines of 150 h.p. each. This was the first twin-engined seaplane turned out by the Friedrichshafen Aircraft Works. One of the features of this machine was the method of mounting the engines. As will be seen from the illustrations (Figs. 17 and 18), the engines were supported by a framework of struts from the bottom plane, and the engine mounting is independent of the wing truss. The stern of the fuselage was built of three-ply wood, and had a Vee bottom m order to act as a tail float, the Vee bottom lessening the shock of the tail coming in contact with a rough sea. In order to protect the tail plane and elevator against the sea the tail plane is mounted on top of the vertical fin and braced by struts. During a number of flights the 35 has proved itself a very good machine. Another remarkable feature of this machine is that all metal fittings in the wings, fuselage and floats were made from solid steel by forging, milling, drilling and planing. Starting handles were provided in front of the radiators.