G.Haddow, P.Grosz The German Giants (Putnam)

Zschach R-Flying-boat Project

   After the war details were published regarding the Zschach R-flying boat. This project was originally intended to produce a large naval bomber, but there is some question as to whether it received consideration by the German Navy. Nevertheless, the aircraft was an interesting design, and as such merits description.
   The flying-boat was designed by R. Zschach, an engineer who had been employed by the Hannoversche Waggonfabrik during the war, and it reflected the same careful design which characterized the Hannover two-seater fighters. The compartmented twin hulls were quite modern in appearance, and each contained two 260 h.p. Mercedes D.IVa engines coupled to a central gear-box, which in turn drove a single propeller mounted in the wing gap high above the influence of sea spray. Fuel was contained in three large tanks mounted below the engines. It was planned to arm the port bow and starboard dorsal gun positions with machine cannons, and the opposite positions were to be equipped with machine-gun. A wireless station was located in the port bow.
   The hulls were joined by two robust struts at the centre section and by the tail assembly at the rear. Communication was provided by a covered ladder shaft which led from each hull to a centrally located control cabin attached •to the underside of the upper wing. The cabin provided space for two pilots, one commander/navigator and, in the rear, for a substantial load of bombs. A fifth machinegun post was situated near the leading edge of the upper wing above the cabin.
   Both wings had slight dihedral and were of equal chord. The outer section of the wing, with its canted struts and balanced inverse-tapered ailerons, was very reminiscent of the Hannover Cl.II and Cl.III fighters.
   The biplane tail unit, supported by two large fixed fins, mounted three rudders, but only the centre one was balanced, as were the twin elevators.
   In its civilian version the Zschach flying-boat was intended to transport fifty passengers in the hulls, and a crew of five comprised of two engine mechanics, two pilots and an aircraft captain. Neither the military nor civil version of this aircraft progressed beyond the project stage, but it remains an aircraft which had pleasing lines and was modern in concept.


SPECIFICATIONS

Type: Zschach R-Flying-boat Project
   Manufacturer: Designed by R. Zschach
   Dimensions:
   Span, 42•7 m. (140 ft. 1 in.)
   Chord, 5 m. (16 ft. 5 in.)
   Gap, 4•75 m. (15 ft. 7 in.)
   Stagger, 0•25 m. (10 in.)
   Length, 22•8 m. (74 ft. 9 1/2 in.)
   Height, 7 m. (22 ft. 11 1/2 in.)
   Hull centres, 7 m. (22 ft. 11 1/2 in.)
   Tail span, 9 m. (29 ft. 6 in.)
   Chord, 2•2 m. (7 ft. 2 1/2 in.)
   Gap, 2 m. (6 ft. 6 1/2 in.)
   Propeller diameter, 4 m. (13 ft. 1 1/2 in.)
   Areas: Wings, 350 sq. m. (3766 sq. ft.)
   Weights (Est.):
   Hull, 1,200 kg.
   Wings, 1,950 kg.
   Control cabin, 210 kg.
   Tail unit, 165 kg.
   Engines, 1,770 kg.
   Transmission, 700 kg.
   Radiators, 200 kg.
   Electrical equipment, 160 kg.
   Fuel, 3,000 kg.
   Armament, 1,105 kg.
   Crew, 810kg.
   Miscellaneous, 730 kg.
   ----
   Loaded, 12,000 kg. (26,460 lb.)
   Wing Loading: 34•3 kg./sq. m. (7 lb./sq. ft.)
   Performance (Est.):
   Speed, 128-140 km.h. (79'5 to 87 m.p.h.)
   Climb, 3000 m. (9843 ft.) in 80 mins.