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

KONDOR D 1 Germany

   Designed by Rethel and Ehrhardt in parallel with the triplane,the D 1 single-seat fighter was an unequal-span single-bay staggered biplane powered by a 100 hp Gnome-Monosoupape rotary engine. Following Albatros practice in having a single-spar lower wing with V-type interplane strutting, the D 1 was dubbed unofficially and somewhat scathingly as the Kondorlaus and was extensively test flown by Ehrhardt. Intended armament comprised two synchronised LMG 08/15 machine guns with 500 rounds. Flight testing was initiated in the late autumn of 1917, but performance proved disappointing, this possibly being the cause of the prototype's unofficial appellation. In the spring of 1918, when Ehrhardt left the Kondor Flugzeugwerke for health reasons, redesign of the aircraft was undertaken by Walter Rethel as the D 2.

Empty weight, 855 lb (388 kg).
Loaded weight, 1,252 lb (568 kg).
Span, 24 ft 11 1/4 in (7,60 m).
Length, 15 ft 10 7/8 in (4,85 m).
Height, 7 ft 10 1/2 in (2,40 m).
Wing area, 143.7 sq ft (13,35 m2).


KONDOR D 2 Germany

   The D 2 single-seat fighter was essentially similar to the D 1, but changes included a two-spar lower wing with parallel interplane bracing struts. Power was provided by a 110 hp Oberursel Ur II rotary engine and armament comprised two synchronised LMG 08/15 machine guns. The D 2 was first flown in May 1918, and two examples participated in the second D-type contest held at Adlershof in June 1918. These were temporarily referred to for convenience as the D I (w/n 200) and D II (w/n 201), one having ailerons on all four wings and one apparently having ailerons on the upper wings only. Oblt Herman Goring, in his report on the potential of these Kondor fighters, gave his opinion that they were "very fine in regard to flight characteristics, but not worthy of further consideration owing to their poor performance". No further development of the D 2 was undertaken.

Max speed, 109 mph (175 km/h).
Time to 9,840 ft (3 000 m), 10.4 min.
Endurance, 1.5 hrs.
Empty weight, 838 lb (380 kg).
Loaded weight, 1,235 lb (560 kg).
Span, 24 ft 10 4/5 in (7,59 m).
Length, 15 ft 11 3/4 in (4,87 m).
Height, 7 ft 10 9/10 in (2,41m).
Wing area, 143.59 sq ft (13,34 m2).

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

Kondor D.I

   At the First Fighter Competition Kondor made an entry despite not have designed a fighter before. The Kondor D.I was a neat little fighter with single-spar lower wing and was powered by the 110 hp Oberursel Ur.II.
   Comparable in technology with the Nieuport 17 of late 1916 with its single-spar lower wing and modestly powered rotary engine, the Kondor D.I was clearly not competitive and did not compete in the competition. Unfortunately, no performance data are available. The D.I designation was a factory, not a military, designation.


Kondor D.II & D.VI

   Despite making no impression at the First Fighter Competition with its D.I, which was present but did not compete, Kondor became more active in designing fighters and fielded two D.II prototypes, Work Number 200 and Work Number 201, for the Second Fighter Competition. Again, the designations were for factory convenience and not official Idflieg designations. The D.III-D.V were not built.
   The Kondor D.II was derived from the earlier D.I by replacing the single-spar lower wing with a new, stronger two-spar wing fitted with ailerons. The revised wing cellule was stronger, gave better performance, and better roll rate for excellent maneuverability. Both Kondor D.II prototypes were powered by the 110 hp Oberursel Ur.II rotary. They were the smallest fighters at the Second Fighter Competition.
   At the competition the Kondor D.II was assessed as having very fine flight characteristics but poor performance, especially the mediocre climb, and there was no chance of a production order.
<...>

Kondor D.II Specifications
Engine: 110 hp Oberursel Ur.II
Wing: Span 7.59 m
Wing Area 13.34 m2
General: Length 4.87 m
Height 2.41m
Empty Weight 380 kg
Loaded Weight 560 kg
Maximum Speed: 175 km/h
Climb: 3000m 10.4 min
5000m 30.5 min

M.Dusing German Aviation Industry in WWI. Volume 1 (A Centennial Perspective on Great War Airplanes 84)

Kondor-Flugzeugwerke, Essen (Kon)

Aircraft Development:

<...>
  In the meantime, a subsidiary company had been established in Nordhausen/Harz, where the Kondor flight school was located, which was called “Kondor-Werk, Gesellschaft fur Holzbearbeitung mbH”. Another company division, “Kondor-Flugzeugwerke GmbH Abt. Sagewerk” in Lemgo/Lippe, was added in 1918 by taking over the Schnackenback sawmill, because good wood and its good processing were essential for aircraft construction. And a lot of it was needed.
  While previously only training aircraft had been built, the first fighter aircraft was built in 1918, the Kondor D.I. It was a normal braced biplane with a round plywood fuselage and V-stems. It was equipped with a 110 HP Oberursel UR.II engine and took part in the second comparison flight in June 1918 in Berlin-Adlershof.
  The Kondor D.II also took part in the same test flight. It was an improved version of the Kondor D.I. The engine remained the same. The V-struts were replaced by II-struts. An interesting feature of the Kondor D.II was that the ailerons were not only on the upper wing, but also on the lower wing.
<...>