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

LOHNER Typ AA (10.20A) Austria-Hungary

   During 1916, the Lohnerwerke of Vienna received a contract from the K.u.K.Luftfahrttruppen (Imperial and Royal Air Service of the Austro-Hungarian Army) for four single-seat fighter prototypes powered by the 185 hp Austro-Daimler six-cylinder inline engine. The first of these, the Lohner 10.20, or Typ AA, appeared at Aspern on 5 September 1916. A single-bay biplane with an armament of twin synchronised Schwarzlose machine guns, the Lohner 10.20 was characterised by a singularly abbreviated and deep, slab-sided fuselage. This was suspended between the wings by a short, inverted-Vee cabane and the faired struts supported the undercarriage. The wing cellule had broad, aerofoil-section I-type struts, and the vertical tail possessed no fixed surface. Taxying trials revealed insufficient control. The rudder area was increased several times and the fuselage lengthened before the aircraft flew on 29 December 1916. The fighter demonstrated poor stability, and, after suffering severe damage in February 1917, was returned to the Lohnerwerke for repair and extensive modification. The aircraft re-emerged in the following month as the Lohner 10.20A, the lower wing having been raised to the base of the fuselage, the cabane being eliminated, a twin-strutted wing cellule being adopted, the fuselage being lengthened and the redesigned tail surfaces embodying a fixed fin. The Lohner 10.20A was destroyed in a crash on 6 June 1917, and no data relating to this type are recorded.


LOHNER TYP AA (10.20B) Austria-Hungary

   The second fighter prototype from the Lohnerwerke, the 10.20B (later redesignated 111.02), possessed essentially similar wing and tail surfaces to those of the 10.20A. It had a "wireless” wing cabane, however, which reverted to aerofoil-section I-struts supplemented by inclined Vee-struts. It also introduced a deep dorsal fin. Powered by a similar 185 hp Austro-Daimler engine to that of its predecessor and carrying a twin-Schwarzlose gun armament, the Lohner 10.20B made its initial flight at Aspern on 2 June 1917. The prototype was taken over by the K.u.K.Luftfahrttruppen in August 1917, and official trials continued through October when further development was halted. No data relating to this type are available.


LOHNER TYP AA (111.03) Austria-Hungary

   The third Typ AA series prototype produced by the Lohnerwerke, the 111.03 differed from its immediate predecessor, the 10.20B alias 111.02, in having a conventional wire-braced wing cellule, a redesigned rudder and unfaired undercarriage strutting. Retaining the 185 hp Austro-Daimler engine, the Lohner 111.03 was flown for the first time on 28 June 1917, and flight testing continued through October. At this stage, the Lohnerwerke was assigned a manufacturing licence for the Aviatik D I, and further development of the Typ AA series was ended.

Max speed, 120 mph (193 km/h).
Time to 3,280 ft (1 000 m), 2.66 min.
Range, 240 mis (386 km).
Empty weight, 1,373 lb (623 kg).
Loaded weight, 2,085 lb (946 kg).
Span, 24 ft 11 1/4 in (7,60 m).
Length, 20 ft 10 in (6,35m).
Height, 9 ft 10 1/8 in (3,00 m).
Wing area, 215.28 sq ft (20,00 m2).

P.Grosz, G.Haddow, P.Shiemer Austro-Hungarian Army Aircraft of World War One (Flying Machines)

Lohner D.I Series 111

  Flars approved the development of the Lohner D.I (Type AA) fighter in August 1916 and ordered four prototypes, three biplanes and one triplane. Designed by Leopold Bauer, the first prototype, designated 10.20, made its debut at Aspern on 5 September 1916. Powered by a 160 hp Daimler engine, it was ground tested by Lohner pilot Karl Kriger, who was to receive Kr 2000 for performing the maiden flight. On 26 October Flars warned Lohner not to fly the aircraft unless the following problems were corrected: the taxiing stability was poor, the control surfaces were too small, the undercarriage lacked shock cords, and the poor visibility made ground maneuvers hazardous. It was returned to the factory for modification on 31 October.
  The 10.20 re-appeared at Aspern on 17 November with a lengthened fuselage. Taxi trials, beginning on 23 November, showed insufficient rudder area but an enlarged rudder tested on 17 December failed to improve ground control. After a tail fin and larger rudder were installed, the rudder response was judged satisfactory and on 29 December 1916, Kriger performed a short hop, believed to be the maiden flight. Upon landing several wing ribs broke. New wings were fitted on 31 December 1916. Flars, contending that the modified prototype "had no future," withheld additional funds but testing of the D.I prototype continued although there was no hope of production. Between 6 January and 28 January 1917, Kriger performed a series of test flights that, despite a severe tail-heavy condition, demonstrated satisfactory performance. Attempts to correct the tail-heaviness were moderately successful, but on 14 February, the 10.20 was damaged in a forced landing and returned to the factory for modification.
  When the much-altered 10.20, now designated 10.20A (later D.I 111.01) returned to Aspern on 3 March 1917, it was fitted with twin-strutted wings. Kriger performed the maiden flight on 4 March with satisfactory results. After a series of test flights in April, some with Oberleutnant Oskar Fekete at the controls, the 10.20A (111.01) was accepted by Flars on 29 April 1917. Sporadic trials continued until 6 June 1917, when the prototype was demolished by Oberleutnant Ludwig Hautzmayer, who was lucky to escape with his life. Kriger had warned that the 10.20A required a highly-skilled pilot.
  Meanwhile, Lohner had completed the second Type AA prototype, designated 10.20B (later D.I 111.02). Virtually a new design, a raised fin running from cockpit to tail now graced the fuselage, and a more powerful 185 hp Daimler engine was installed. The I-strutted wing cellule was braced to the fuselage by a pair of V-struts, which eliminated the need for interplane wires. Kriger, who performed the maiden flight on 2 June 1917 at Aspern, reported a "fair amount of nose-heaviness." Flight testing continued in June-July. On 2 August, the 10.20B was accepted by Flars, and Lohner pilot Kriger continued flight testing the fighter through October 1917. The 10.20B (111.02) was based at Aspern in February 1918, and last reported at Flugpark 1 in March 1918.
  Following close on the heels of the 10.20B, the third Type AA prototype, D.I 111.03 (a prototype number was not assigned), was assembled at Aspern on 25 June 1917. Of conventional layout, the 111.03 had a large tail fin, a wire-braced wing cellule, and a 185 hp Daimler engine supplied the power. The maiden flight was performed by Kriger on 28 June 1917. A few test flights were recorded through October 1917, when further investigation of the type stopped. The D.I 111.03 was reported at Aspern in February 1918, sent to Flek 6 as an instruction airframe in March, and written-off in August 1918.

Lohner 10.20 (D.I 111.01) Specifications
First Version, I-Strut
Engine: 160 hp Daimler
Wing: Span Upper 6.55 m (21.49 ft)
Span Lower 6.00 m (19.68 ft)
Total Wing Area 16.12 sq m (173 sq ft)
General: Length 4.70 m (15.42 ft)
Height 2.90 m (9.51 ft)

Lohner 10.20A (D.I 111.01) Specifications
Third Version, Twin Struts
Engine: 160 hp Daimler
Wing: Span Upper 7.00 m (22.97 ft)
Span Lower 7.00 m (22.97 ft)
Chord Upper 1.50 m (4.92 ft)
Chord Lower 1.50 m (4.92 ft)
General: Empty Weight 570 kg (1257 lb)
Loaded Weight 826 kg (1821 lb)

Lohner 10.20B (D.I 111.02) Specifications
Engine: 185 hp Daimler
Wing: Span Upper 7.30 m (23.95 ft)
Span Lower 6.70 m (21.98 ft)
Total Wing Area 17.98 sq m (193 sq ft)
General: Length 6.00 m (19.68 ft)
Height 2.95 m (9.68 ft)

Lohner D.I 111.03 Specifications
Engine: 185 hp Daimler
Wing: Span Upper 7.60 m (24.93 ft)
Span Lower 7.60 m (24.93 ft)
Chord Upper 1.50m (4.92 ft)
Total Wing Area 20 sq m (2.15 sq ft)
General: Length 6.35 m (20.83 ft)
Height 3.00 m (9.84 ft)
Empty Weight 623 kg (1374 lb)
Loaded Weight 889 kg (1960 lb)
Maximum Speed: 175 km/hr (109 mph)
Climb: 1000m (3,281 ft) in 2 min 40 sec

E.Hauke, W.Schroeder, B.Totschinger Die Flugzeuge der k.u.k. Luftfahrtruppe und Seeflieger 1914-1918

10. Flugzeuge der Fabrik Jacob Löhner & Co. Wien, Floridsdorf
10.20 Löhner DD Type AA Dm 160
10.20 Löhner DD Type AA (verlängert) Dm 160
10.20B Löhner DD Type AA (Umbau; nach nochmaligem Umbau neue Bezeichnung 111.03) Dm 160
111.01 — 111.02 Löhner AA Dm 185
111.03 Löhner AA (ex 10.20B) Dm 185