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

L.V.G. C VIII
   Final two-seater to emerge from the L.V.G. factory during the First World War was the C VIII of 1918. Although not vastly different from the C VI, there were larger and shallower cut-outs in the wings and ailerons with a link strut fitted at all four wingtips. The high-compression 200 h.p. Benz IV u. engine developed some 240 h.p. at rated altitude and was fitted with a large car-type radiator on the extreme nose. Only one aircraft was completed. Engine, 200 h.p. Benz Bz IV u. Span, 13.0 m. (42 ft. 7 7/8 in.). Length, 7.0 m. (22 ft. 11 5/8 in.). Height, 2.8 m. (9 ft. 2 1/4 in.). Area, 35.7 sq.m. (386 sq.ft.). Weights: Empty, 975 kg. (2,145 lb.). Loaded, 1,380 kg. (3,036 lb.). Speed, 165km.hr.(103.125 m.p.h.). Duration,4hr. Armament, one Spandau and one Parabellum machine-guns.

J.Herris LVG Aircraft of WWI. Vol.1: B-Types & C.I (A Centennial Perspective on Great War Airplanes 34)

LVG C-Types
  
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  At this point the history of LVG C-types becomes obscure. The next documented LVG C-type is the C.VIII, a handsome biplane with car-type radiator in the nose that was intended to replace the C.VI in production. As far as is known, only a single C.VIII prototype was completed before the Armistice.
  But what about the missing LVG C.VII? One source describes the LVG C.VII as an improved LVG B.III powered by a 160 hp Mercedes D.III engine built in 1918 and intended for use as a trainer. This may be true, but there is no confirmation and no photos of the type that have been identified. If this is true, then the logical hole between the C.VI and C.VIII is neatly filled.
  But it gets worse, as a photo exists of the LVG C.XI(Schul)! This aircraft matches the description given of the LVG C.VII; a modified B.III intended for training and built by Schutte-Lanz as indicated by the "Schul" suffix. The existence of the C.XI(Schul) then raises the question of what are the LVG C.IX and C.X, now the missing numbers in the series? These aircraft may well have been variations of the C.XI(Schul), perhaps with different engines or equipment, or perhaps designations assigned to versions of the C.XI(Schul) built by different manufacturers. Unfortunately for those who like tidy solutions for historical questions, currently no documentation of these 'missing' types in the LVG C-type numbering sequence has been found. Neither have photos of these missing types been identified.
  

LVG C-Type Specifications
LVG C.V LVG C.VI LVG C.VIII LVG C.XI(Schul)
Engine 200 hp Benz Bz.IV 220 hp Benz Bz.IVa 240 hp Benz Bz.IVu 160 hp Mercedes D.III
Span, Upper 13.60 m 13.0 m 13.0 m -
Span, Lower 12.83 m - - -
Chord, Upper 1.75 m - - -
Chord, Lower 1.60 m - - -
Gap 1.73 m - - -
Wing Area 40.5 m2 34.6 m2 35.7 m2 -
Length 8.07 m 7.45 m 7.0 m -
Height 3.36 m 2.8 m 2.8 m -
Empty Weight 1,009 kg 930 kg 975 kg -
Loaded Weight 1,505 kg 1,309 kg 1,380 kg -
Maximum Speed 170 km/h 170 km/h 165 km/h -
Climb to 1,000 m 3 minutes 4 minutes - -
Climb to 2,000 m 7 minutes 8 minutes - -
Climb to 3,000 m 12.5 minutes 15 minutes - -
Climb to 4,000 m 23.5 minutes 25.0 minutes - -
Climb to 6,000 m - 40.0 minutes - -

J.Herris LVG Aircraft of WWI. Vol.3: Types C.VI-C.XI & Fighters (A Centennial Perspective on Great War Airplanes 36)

LVG C.VIII

  The last LVG design for a two-seater combat aircraft was the LVG C.VIII; the C.XI(Schul) and probably the missing designations were all trainers.
  Clearly developed from the successful LVG C.VI, the C.VIII was powered by a 240 hp Benz Bz.IVu high-altitude engine to provide better speed and climb at higher altitudes and give a higher ceiling. A nose radiator was fitted and to improve maneuverability the C.VIII had ailerons on all wings with actuating struts between the ailerons on upper
and lower wings.
  As the photo on this page shows, the LVG C.VIII was completed in August 1918 and photographed on 30 August. As far as is known, only one C.VIII was built. Apparently development did not progress fast enough for the C.VIII to be ordered into production before the Armistice. The airframe used a conventional structure and aerodynamics proven in the successful C.VI, so perhaps the pacing item was development or production of the high-altitude engine or difficulties with the nose radiator. In any case, the C.VIII was the end LVG combat two-seater development.

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

Luftverkehrsgesellschaft mbH, Berlin-Johannisthal, (LVG)

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  At the suggestion of the Flugzeugmeisterei, the company decided to build a C-airplane LVG C.VI with a 200 hp Benz engine Bz.IIIa, which started its first test flights in mid-1918. In addition to this type, another C-airplane C.VIII with over-compressed Benz engine Bz.IIIau was constructed on the basis of the B.III training machine. However, this development was completed too late to be used.
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