Jane's All The Worlds Aircraft 1910-1911 has a number of German projects and prototypes described. Experience has shown that the data is not 100% accurate in the early Jane's, especially in the designations. I think additional entries might compliment Tuizentfloot's earlier postings
Auffm-Ordt Monoplane
Early machine from 1908. Design based on Demoiselle layout.
Alexander Baumann, Stuttgart-Untertürkheim (mentioned in Tuizentfloot's postings)
Triplane 25 hp Grade engine which was completed in 1909. Flew 150 m at Hannover. Wing Area: 323 sq ft (30 m2), Weight: 573 lb (260 kg)
Buschmann, Regierungsbaumeister, Berlin (mentioned in Tuizentfloot's postings)
Helicopter from 1910 with a 6 hp engine and a rotor diameter of 63.75 ft (20 m).
Karl Buttenstedt, Berlin (mentioned in Tuizentfloot's postings)
Monoplane with engine and tractor propeller and a special feature of variable wings.
Coler Monoplane
Aircraft powered by a 90 hp egine driving two propellers. Under construction 1910. Wing Area 1,012 sq ft (94 m2)
Delfosse Monplane
Mid-wing tractor monoplane with a 24 hp Delfosse motor. Wing Area: 302 sq ft (28 sq m), weight: 320 lb (145 kg)
Dorner (Dornier?) Monoplane
High wing tractor with a 24 hp engine. Completed 1909. Didn't fly until March 1910 when it was aloft for 6 minutes. Burned 1910. Wing Area: 302 sq ft (28 sq m), weight: 617 lb (280 kg)
Ganz Gabrice Monoplanes
Gabrice I
A monoplane started in May 1909 fitted with a small Buchet engine. Not completed.
Gabrice II
A monoplane started in 1909 fitted with a small Buchet engine. Not completed.
Jatho Aeroplanes
Jatho I
An astriplane (sic) built in 1899, did not fly.
Jatho II
An aeroplane built in 1906, a machine which, by shifting the angle of inclination of the body, both planes were used as elevators in leaving the ground.
Jatho III
A canard biplane built in 1909, with a single engine.
Kaiser Biplane
Biplane built by Gebr. Kaiser at Beuggen in 1909 as a glider. Fitted with an engine in 1910. Unsuccesful.
Meschner Biplane, Berlin
Biplane built and tested started at Tempelhof in December 1908. Chassis made of aluminium tubes with welded steel ribs. Wings were of a warping type. Engine power provided by a 70 hp Koerting water-cooled unit which drove a 3 bladed airscrew. Top speed: 37 mph (60 km/h). No further details.
Paul M. Neumann, Johannisthal bei Berlin (mentioned in Tuizentfloot's postings)
Tandem biplane designed to carry four persons and was designed for military purposes. One 60 hp engine which drove four propellers. Made a flight in March 1910 when it was badly damaged.
Schnädelbach & Berner, Sachsen (mentioned in Tuizentfloot's postings)
Referred to as a Schmaedelbach & Berner Ornithopter. Weight 827 lb (375 kg). In 1909 this flew 500 m at Zurickau.
Schnell Monoplane, Linden
Under construction 1909, no record of completion. Main plane curved slightly rearward and at the tips forward.Wing Area: 161 sg ft (15 sq m), Total Weight: 331 lb (150 kg).
Richard Scholz,Schulzendorf bei Berlin (mentioned in Tuizentfloot's postings)
Built a flying device in 1908-9 at great expense. failed to fly and around December 1909 the experiments were abandoned. Machine lay derelict in a field thereafter.
Otto Schubert Monoplane
Antoinette engine and two Ruthenberg propellers. Any earlier model was destroyed in a gale in November 1909 (Tuizentfloot's flying device with two winged wheels?)
Max Schuler, Chemnitz
Welded steel frame monted on four wheels, one in front, one central at rear and one under each wing tip. Two propellers mounted to the rear of the wings which were chain driven in opposite directions. Described as a compromise between a Wright and a Voisin design. Wing Span: 39.5 ft (12.5 m) , Wing Area: 565 sq ft (53 m2)
Sternemann, Hamburg (mentioned in Tuizentfloot's postings)
Helicopter design (Jan called the manufacturer Sternmann) with twin rotors at different heights. The upper one was 23 ft (7 m) diameter, lower one was 16.5 ft (5 m) diameter. Lift was stated as 416 kg per sq m. Flew October 1910.
Dr. Karl Vollmoeller, Stuttgart
Volmoller III
A monoplane with a 14 hp Anzani motor. Completed in November 1909. It made flights in stuttgart over short distances. Wing area 129 sq ft (12 sq m)
Volmoller IV
A monoplane with a 25 hp engine under construction in 1910. Wing area 215 sq ft (20 sq m)
Source: All The World's Aircraft 1910-11 (1968 reprint) Edited by Fred T. Jane (Sampson Low)