O.Thetford, P.Gray German Aircraft of the First World War (Putnam)
D.F.W. D I
A 1917 prototype with ply-covered fuselage and car-type radiator at nose. Engine, 160 h.p. Mercedes D III.
D.F.W. D I (modified)
In this model of the D I a rudder of increased area was fitted. Engine, 160 h.p. Mercedes D III. Armament, twin Spandau machine-guns.
D.F.W. D I (final modification)
In this version further revision of the tail surfaces may be noted, and the ailerons at the lower wingtips have been deleted. The photograph was taken at Adlershof in January 1918. Engine, 160 h.p. Mercedes D III. Armament, twin Spandau machine-guns.
D.F.W. F 34
The D II designation sometimes applied to this single-seater is unconfirmed. The aircraft was completed April 1918, but does not appear to have participated in the D types Competitions. Engine, 160 h.p. Mercedes D III. Span, 9.08 m. (29 ft. 9 1/2 in.). Length, 5.5 m. (18 ft. 0 5/8 in.). Area, 23 sq.m. (248.4 sq.ft.). Speed, 177 km.hr. (110.5 m.p.h.). Climb, 1,000 m. (3,280 ft.) in 2 min., 5,000 m. (16,400 ft.) in 20 min. Armament, twin Spandau machine-guns.
W.Green, G.Swanborough The Complete Book of Fighters
DFW D I Germany
The DFW D I (which was subsequently to be referred to on occasions erroneously as the D II and by the unconfirmed and almost certainly incorrect designation of F 34) was a single-bay biplane powered by a 160 hp Mercedes D IIIa engine and mounting the usual pair of synchronised 7,92-mm LMG 08/15 machine guns. Entered in the second D-type contest held in May-June 1918, the DFW DI was rejected out of hand "for any frontline utilisation" and did not participate in the subsequent flight evaluation. During July 1918, however, the D I was rebuilt and flight test results were considered sufficiently promising for full static load tests to be conducted at Adlershof during late July and early August. However, these tests revealed that the fuselage and tail demanded strengthening, and the type was not approved for service use in consequence.
Max speed, 110 mph (177 km/h).
Time to 13,125 ft (4 000 m), 10 min.
Empty weight, 1,409 lb (639 kg).
Loaded weight, 1,806 lb (819 kg).
Span, 29 ft 9 1/2 in (9,08 m).
Length, 18 ft 16 in (5,50 m).
Wing area, 247.58 sqft (23,00 m2).
DFW T 34-I Germany
A conventional single-bay biplane of wooden construction powered by a 160 hp Mercedes D III engine and mounting twin synchronised 7,92-mm machine guns, the T 34-I (frequently referred to erroneously as the D I) was developed in mid-1917, first appearing in official Idflieg progress reports in October of that year when the cooling system was being modified and the control surfaces enlarged. In November, new wings with a more efficient rib profile were under construction and, in January 1918, the T 34-I attained an altitude of 16,405 ft (5 000 m) in 22 min, a climb capability possessed by the Pfalz D IIIa already in operational service. By this time, the ailerons had been removed from the lower wing and the vertical tail surfaces had undergone further redesign, and in this form the T 34-I was entered in the first D-type contest at Adlershof in February 1918. It was rejected on the score of poor cockpit visibility prior to the flight evaluation and thus did not appear in the official statistical tabulations. No data on the T 34-I are available.
J.Herris DFW Aircraft of WWI (A Centennial Perspective on Great War Airplanes 29)
Following the bizarre "Flea" DFW next designed the conventional T 34 fighter in both biplane (T 34-I) and triplane (T 34-II) forms and entered them in the First Fighter Competition. These two fighter prototypes shared everything but the wing cellule.
Both T 34 designs were powered by a 160 hp Mercedes D.III engine and were armed with two machine-guns. Photographic evidence shows that the biplane fighter was evaluated in at least three different configurations in a quest to improve maneuverability and handling qualities.
Both the biplane and triplane were submitted to the First Fighter Competition but were excluded from flight testing due to poor field of view for the pilot. No performance or dimensional data is available.
Despite its earlier failures with the bizarre "Flea", disappointing T 34-I biplane, and the overly bestrutted T 34-II triplane, DFW persevered with fighter development and the clean, conventional DFW D.II, powered by a 170 hp Mercedes D.IIIa engine, was entered in the Second Fighter Competition. Again the DFW entry was rejected "for any front-line use" before flight evaluations began and again the type did not appear in the subsequent tables of data.
However, the D.II was rebuilt in July and was promising enough that it underwent the full set of static load tests. Unfortunately, the tests revealed structural weaknesses in the fuselage and tail and D.II development was terminated. It could not have helped that it was slower than the DFW "Flea".