G.Haddow, P.Grosz The German Giants (Putnam)
Neuber R-plane Project
With the apparent success of ground and flight tests on the VGO.II of the downward firing cannon designed by Lt. Dr. Ernst Neuber for attacking ground targets from an R-plane, an order was placed for a 10•5 cm. calibre cannon on 7 November 1917. To transport this cannon over enemy targets, Neuber proposed a cannon-carrying R-plane based on his patent No. 305,039. The patent described a conventional biplane airframe with the inner structure (consisting of the centre fuselage, engine mounts and cannon support) specially reinforced to absorb the recoil forces of the cannon which was mounted amidships. It was calculated that the inner structure's 7000 kg. weight and strength would be sufficient to absorb the 3000 kg. recoil. The aircraft was to be powered by eight 245 h.p. Maybach Mb.IVa engines mounted in streamlined, fully-enclosed nacelles. Two engines each were geared to drive the tractor and pusher propellers. The larger tractor propellers were to run at 900-1000 r.p.m. and the pusher propellers in an opposite direction at 1300 to 1400 r.p.m.
The armament was to consist of one 10•5 calibre cannon for attacking ground targets and battleships. A total of 110-120 rounds of ammunition was provided for the cannon, which had a rate of fire of 20 rounds per minute (called a three-quarter automatic cannon by the Germans). One man would aim and fire while a second loaded the cannon. Eight machine-guns comprised the defensive armament. Each of the four gun turrets was to have two guns and, if necessary, several machineguns could be mounted in sliding side doors. The large gun turrets were located in the extreme nose, in the upper and lower rear fuselage and on a small projecting platform located underneath the pilot's cockpit. Should it be required, machine cannon could be included as defensive armament. Armour plating was provided for the pilots' seats and the fuel tanks. A teardrop shaped command post was proposed for the upper wing centre section from which the aircraft commander could follow the aircraft's movements and give commands by means of a machine telegraph. In all other aspects the Neuber project was rather conventional, outside of being somewhat larger than existing R-planes.
Type: Neuber Cannon-carrying R-plane Project
Manufacturer: Designed by Lt. Dr. Ernst Neuber
Engines: Eight 245 h.p. Maybach Mb.IVa engines
Span, 54•5 m. (178 ft. 9 1/2 in.)
Length, 33•5 m. (109 ft. 10 1/2 in.)
Height, 6•5 m. (21 ft. 3 1/2 in.)
Chord, 6•0 m. (19 ft. 8 1/2 in.)
Gap, 6•0 m. (19 ft. 8 1/2 in.)
Wing Loading: 30 kg./sq. m. (6•14 lb./sq. ft.)
Performance: Range, 900 km. (559 miles)
Armament: One 10•5 cm. cannon with 110-120 rounds of ammunition: eight machine-guns