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

A.E.G. C VIII
   An experimental single-bay two-seater of Oct. 1917. Multi-spar wings "ear"-type radiators and tail surfaces quite unlike previous A.E.G. designs. Engine, 160 h.p. Mercedes D III. Span, 9.5 m. (31 ft. 2 in.). Length, 6.9 m. (22 ft. 7 3/4 in.). Weights: Empty, 800 kg. (1,760 lb.). Loaded, 1,160 kg. (2,552 lb.). Speed, 170 km.hr. (106.25 m.p.h.). Climb, 1,000 m. (3,280 ft.) in 3.8 min.

A.E.G. C VIII Dr
   This triplane version of the C VIII showed no improvement in climb, and speed was reduced to 165 km.hr. (103.12 m.p.h.). It appeared in December 1917 and did not develop beyond an experiment. Engine, 160 h.p. Mercedes D III. Span, Upper 11.2 m. (36 ft. 9 in.); Middle 10.8 m. (35 ft. 5 1/4 in.); Lower, 10.4 m. (35 ft. 1 1/4 in.). Otherwise as C VIII.

J.Herris AEG Aircraft of WWI (A Centennial Perspective on Great War Airplanes 16)

AEG C.VIII & C.VIII Triplane

   The AEG C.VIII was an attempt by AEG to improve the C.VII for the light two-seater escort role. Three prototypes were ordered, all powered by the 160 hp Mercedes D.III. Apparently two were completed as biplanes, the first in July 1917, and the third as a triplane. It should be remembered that the summer of 1917 was the height of Idflieg’s triplane craze, which no doubt influenced AEG to complete one C.VIII as a triplane. AEG apparently hoped to achieve high speed by reducing drag to a minimum; the AEG history claims 190 km/h but engineering specifications show a top speed of 170 km/h. If the higher speed were actually achieved the C.VIII might have been ordered into production, but it was not and a reasonable conclusion is the 190 km/h top speed was not reached.
   The C.VIII triplane used the engine, fuselage, and tail of the biplane C.VIII. Completed in October 1917 and flight tested in November, the C.VIII triplane climbed to 5000 meters in 34 minutes, a climb equivalent to the Albatros D.V single-seat fighter. With 80 kg less load it climbed to 5000 meters in 24 minutes. However, it was slower than the biplane C.VIII and flight-testing revealed the C.VIII triplane to have unsatisfactory flying qualities. AEG had proposed a smaller, lighter triplane in November but the disappointing flight-test results of the C.VIII triplane eliminated that idea as well.


AEG C-Type Specifications
C.V C.VII C.VIII C.VIIIDr
Engine 220 hp Mercedes D.IV 160 hp Mercedes D.III 160 hp Mercedes D.III 160 hp Mercedes D.III
Span Upper 13.26 m 11.10m 9.50 m 11.20 m
Span Lower 12.45 m 10.05 m 9.10m 10.40 m
Chord Upper 1.75 m 1.55 m 1.74 m 1.45 m
Chord Lower 1.75 m 1.30 m 1.33 m 0.82 m
Gap 2.07 m 1.85 m 1.60 m 1.00 m
Wing Area 41.5 m2 26.0 m2 22.67 m2 31.0 m2
Length 7.60 m 6.20 m 6.20 m 6.90 m
Track 2.30 m 2.00 m 2.10 m 1.90 m
Empty Weight 900 kg 758 kg 800 kg 800 kg
Loaded Weight 1,432 kg 1,118 kg 1,160 kg 1,160 kg
Maximum Speed 165 kmh 175 kmh 170-190 kmh 158 kmh
Climb, 1000m 7 min. 4 min. 3.8 min. 3.8 min.
Climb, 2000m 13 min. - - -
Climb, 3000m 22 min. - - -
Climb, 4000m 37.5 min. - - -
Armament 1 fixed & 1 flexible machine gun 1 fixed & 1 flexible machine gun 1 fixed & 1 flexible machine gun 1 fixed & 1 flexible machine gun

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

Allgemeine Elektrizitats-Gesellschaft, Flugzeugfabrik, Hennigsdorf (AEG)

Aircraft Development:

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  Meanwhile, another series of aircraft types were created on an experimental basis, intended as light C airplanes, of which type AEG C.VII met the higher climb rates required in January 1917. The same type was also built with a single spar for study purposes to increase speed, and flown as the AEG C.VIII, achieved a speed of 190 km/h. As a triplane, very good climb rates were additionally achieved.
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