O.Thetford, P.Gray German Aircraft of the First World War (Putnam)

Daimler L 6 and D I
   Previously having built other manufacturers' products under licence (FF G III, G IV, etc.), the L 6 was the Daimler Motorengesellschaft Werke's first excursion into the single-seater design field. This extremely neat fighter was designed round Daimler's own 185 h.p. D IIIb vee-eight engine. Six aircraft of the type were built, and one participated in the second D types Competition at Adlershof during the May-June 1918 period. Three test climbs to 5,000 m. (16,400 ft.) were made at a loaded weight of 922 kg. (2,028 lb.), and recorded times of 19.4 min., 21.4 min. and 16.8 min. All tests were made with the same airscrew, a "Propulsor" of 3.1 m. diameter and 2.85 m. pitch, which illustrates how performance varied, even with one aircraft. Armament, twin Spandau machine-guns.


Daimler L 9
   Single-seat fighter developed from D I. Revised tail surfaces and interplane bracing struts. Prototype only built. Large lifting surface fairing over the axle as on Fokker types. Engine, 185 h.p. Daimler D IIIb.

W.Green, G.Swanborough The Complete Book of Fighters

DAIMLER L 6 (D I) Germany

   During the summer of 1915, the Daimler Motoren-Gesellschaft established an aircraft division at the request of the Inspektion der Fliegertruppen (Idflieg). In 1917, this Flugzeug Abteilung initiated work on an original single-seat fighter to the design of Ing Karl Schopper and powered by the company’s new D IIIb eight-cylinder water-cooled engine. Flight testing of this, the L 6 (or D I) equi-span single-bay biplane, was delayed until late November 1917 by engine bearing problems. Tail heaviness was rectified by modification of the wing cellule arrangement, flight testing was completed in March 1918, and the L 6 was sent to Adlershof for Typprufung in July, concurrently participating in the second D-Type Competition. Performance suffered owing to the fact that the D nib engine, which was rated at 185 hp, lost power at altitude, but a contract for 20 examples of the Daimler fighter was awarded on 23 July 1918. These aircraft, which were armed with synchronised 7,92-mm LMG 08/15 machine guns, were delivered during December 1918.

Max speed, 114 mph (183 km/h).
Time to 19,685 ft (6 000 m), 30 min.
Endurance, 2 hrs.
Empty weight, 1,653 lb (750 kg).
Loaded weight, 2,039 lb (925 kg).
Span, 32 ft 5 3/4 in (9,90 m).
Length, 23 ft 11 2/5 in (7,30 m).
Height, 9 ft 0 2/3 in (2,76 m).
Wing area, 243.27 sq ft (22,60 m2).


DAIMLER L 9 (D II) Germany

   Essentially a refined development of the L 6, dispensing with interplane bracing wires and having staggered wings and new vertical tail surfaces, the L 9 single-seat fighter employed a similar 186 hp Daimler D IIIb engine. It was intended to carry an armament of twin synchronised 7,92-mm LMG 08/15 machine guns. Flown initially with fully cantilevered wings in July 1918, the L 9 was modified during August by the addition of aerofoil-section I-type interplane bracing struts. Hanns Klemm had joined Daimler's Flugzeug Abteilung as chief designer on 1 April 1918, and the L 9 apparently embodied some of his ideas. Only one prototype was completed and no production contract was awarded. Daimler offered the L 9 in modified form for use on postal services in 1920, but failed to obtain a purchaser.

Max speed, 118 mph (190 km/h).
Initial climb, 905 ft/min (4,60 m/sec).
Range, 273 mis (440 km).
Empty weight, 1,636 lb (742 kg).
Loaded weight, 2,182 lb (990 kg).
Span, 29 ft 6 1/3 in (9,00 m).
Length, 23 ft 7 1/2 in (7,20 m).
Height, 8 ft 6 1/3 in (2,60 m).
Wing area, 240.25 sqft (22,32 m2).

J.Herris German Aircraft of Minor Manufacturers in WW1. Vol I (A Centennial Perspective on Great War Airplanes 49)

Daimler D.I & D.II

   The Daimler-Motoren-Gesellschaft AG was the largest engine manufacturer in Germany and was well-known for its aircraft engines using the trade name Mercedes. In addition to aero-engine manufacturing, Daimler repaired airplanes, built more than 200 Friedrichshafen bombers under license, and also designed and built prototype combat aircraft, eventually including fighters.
   In September 1917 the prototype 185 hp Mercedes D.IIIb V-8 aircraft engine, based on the Hispano-Suiza, was running well on the test stand, and the company decided to build a prototype fighter to flight-test the engine. The Daimler D.I began flight tests at the end of November with the geared version of the engine, the D.IIIbm. Initially it was tail heavy, but by January that was corrected. However, climb rate was still not satisfactory, and it was not until the Second Fighter Competition that the D.I was ready to compete. There it demonstrated an average climb time to 6,000 meters of 28.5 minutes, a time matched by the competing Aviatik D.IV powered by the 195 hp Benz Bz.IIIbm geared V-8. Front-line pilots did not like the Aviatik, and the Daimler V-8 engine was the Daimler D.I's main advantage. Idflieg ordered 20 Daimler D.I fighters on 23 July, primarily to speed development of the engine. One redesigned D.I was ordered on 22 September.
   Daimler next built a D.II prototype with thick wings and wireless cellule, likely inspired by the Fokker D.VII. The D.II flew in July, too late for the Second Fighter Competition. In late August the D.II flew in comparison with a Fokker D.VII; the D.II proved equal in speed and had a much better climb rate. D.II development continued to the Armistice.


Daimler D.I Specifications
Engine: 185 hp Mercedes D.IIIb V-8
Wing: Span 9.90 m
Area 22.6 m2
General: Length 7.30 m
Height 2.76 m
Empty Weight 750 kg
Loaded Weight 925 kg
Maximum Speed 183 kmh
Climb: 6000 m 30 min


Daimler D.II Specifications
Engine: 185 hp Mercedes D.IIIb V-8
Wing: Span 9.00 m
Area 22.32 m2
General: Length 7.20 m
Height 2.60 m
Empty Weight 742 kg
Loaded Weight 990 kg
Maximum Speed 190 kmh