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

Rumpler C VII and Rubild

   Development of the highly successful Rumpler C IV resulted eventually in the appearance, in late 1917, of the C VII, with still further improved altitude performance. This aircraft was fitted with the "super compressed" (high-compression) 240 h.p. Maybach engine. Although the actual horsepower rating was lower than that of the 260 h.p. Mercedes, the power fall-off at extreme altitudes was much lower, and it was at such heights that the power ratio was seen to advantage. The intermediate C V was actually a development of the C III, and there appears to be no record of a C VI.
   Two versions of the Rumpler C VII existed; the standard machine was used for long-distance reconnaissance and fitted with radio and normal armament of one fixed and one manually operated machine-gun. A special photo-reconnaissance version was known as the C VII (Rubild) and was fitted with specialised camera equipment for most advantageous use at peak altitudes. This model dispensed with the forward gun and ammunition, and all extraneous equipment was kept to a minimum. It was the Rumpler C VII (Rubild) that was the really high-flying Rumpler which often featured in Allied combat reports, and which proved almost impossible to intercept. Its ceiling was in the region of 24,000 ft., and even at 20,000 ft. a speed of 100 m.p.h. could be maintained a superb performance for the period.
   In construction the C VII was almost identical to the C IV and differed only in detail. It was marginally smaller in overall dimensions than the CIV, but the only certain visual identification was by the exhaust manifold, which exhausted sideways to starboard and not upwards as on the earlier machine. The fuselage, as in the C IV, had a basic structure of timber with steel-tube spacers in the forward half of the fuselage. Nose-entry was not so sleek, as spinners were not fitted to C VIIs, simply a bulbous metal panel immediately behind the airscrew. Tail surfaces were of steel-tube framing and retained the earlier profile with the distinctive "wing-nut" profile horizontal surfaces. The reverse camber was still featured, and plain elevators were fitted instead of balanced as formerly.
   Again the wings were as the C IV, but with a reduction of just over 4 1/4 in. in span, a slight increase in chord, however, gave a net increase in area of 1 sq.ft.! Unbalanced ailerons of steel-tube framing were fitted, and all interplane struts and centre-section cabane were interchangeable with those of the C IV. A slightly longer undercarriage chassis gave an increase in height of about 5 1/4 in., which permitted the fitting of airscrews of increased diameter.
   Instances of the efficient performance of these Rumpler machines are cited in reports by Major J. B. McCudden, V.C., 15th December 1917:
   "I dived on him from 19,800 feet for the Hun was at 19,000 feet. I closed on him and opened fire, but as I had mis-judged my speed and was overshooting, I had to turn to avoid running into him. I caught up with him again, but could not defeat him for the pilot was good and gave his gunner every opportunity, and I had to leave him very soon."
   Again on 23rd December 1917:
   "After 15 minutes I got up to his level at 18,200 feet over Peronne. He now saw me and climbed for a little while trying to outclimb me, but he could not for my machine was still going up well; but had we both been at 19,000 feet he could have done so for the Rumplers at 20,000 feet are extremely efficient with their heavily cambered wing, whereas the S.E. 5 at that height, although it is fast, has not much climb on account of its flat wing section. However I was now up at the Rumpler's height and he tried to run for it.
   "I soon got into position but found he was every bit as fast as I was although I was able to keep up with him because he swerved to allow his gunner to fire at me and lost a certain amount of speed. I fought him down from 18,000 feet to 8,000 feet and he tried hard to save his life but after a final burst from both my machine-guns his right hand wings fell off and I very nearly flew into them."
   As may be seen from the first combat, success did not always attend McCudden, and he again failed to get a Rumpler at 19,500 ft. on 3rd January 1918, reporting:
   "I encountered a Rumpler over Bullecourt and fought him a long way east of his lines, but he was an old hand and saved his height instead of losing it and at last I had to leave him for we were now over Douai at 18,000 feet. Here I turned back, for a lucky shot from him might have disabled my engine and have caused me to come down."
   The general immunity of the Rumplers to attack above 18,000 ft. is reflected in the comment by Major McCudden:
   "I expect some of those Huns got a shock when they came over at 18,000 feet a n d were dived upon by an S.E. from above, for in winter it was an exception to the rule to see an S.E. above 17,000 feet, which was the ceiling of the average 200 h.p. S.E. with its war load. My machine had so many little things done to it that I could always go up t o 20,000 feet whenever I liked, and it was mainly the interest I took in my machine which enabled me to get up so high."

TECHNICAL DATA
   Description: Long-range reconnaissance and photo-reconnaissance in Rubild model.
   Manufacturer: Rumpler Flugzeug-Werke G.m.b.H. Johannisthal (Ru.).
   Power Plant: One 240 h.p. Maybach Mb IV 6 cylinder in-line water-cooled engine.
   Dimensions: Span, 12 55 m. (41 ft. 2 1/8 in.). Length, 8.2 m. (26 ft. 10 7/8 in.). Height, 3.39 m. (11 ft. 1 3/8 in.). Area, 33.6 sq.m. (363 sq.ft.).
   Weights: Empty, 1,050 kg. (2,310 lb.). Loaded, 1,485 kg. (3,267 lb.).
   Performance: Climb, 1,000 m. (3,280 ft.) in 2.3 min., speed 175 km.hr. (109.375 m.p.h.); 2,000 m. (6,560 ft.) in 4.3 min.; 3,000 m. (9,840 ft.) in. 8.0 min.; 4,000 m. (13,120 ft.) in 130 min.; 5,000 m. (16,400 ft.) in 21.5 min.; 6,000 m. (19,680 ft.) in 33.0 min, speed 160km.hr. (100 m.p.h.); 7,000 m. (22,960 ft.) in 50.0 min.; Service ceiling 23,944 ft. Duration, ca. 3 1/2 hr.
   Armament: One fixed Spandau machine-gun forward and one manually operated Parabellum machine-gun in rear cockpit. C VII (Rubild) had no forward armament fitted.

   Latest information (Feb. 1970) researched by Peter Grosz from Rumpler documents obtained from the late A. R. Weyl collection would indicate that the Rubild was, in fact, the C VI. There was no outward means of identification.

J.Herris Development of German Warplanes in WWI (A Centennial Perspective on Great War Airplanes 1)

Lichtbildflugzeuge (Specialized PhotoReconnaissance)

   For longer-range, high-altitude reconnaissance the superb Rumpler C.IV was created by installing the powerful 260 hp Mercedes D.IVa into the late-production Rumpler C.III airframe. The C.IV and its many derivatives became the best German high-altitude reconnaissance aircraft. Later models of the Rumpler mounted a variety of over-compressed engines designed to provide more power at high altitude, and these aircraft kept the Rumpler series at the forefront of high-altitude photo-reconnaissance for the rest of the war. Initially categorized as C-types, some of these specialized aircraft were later designated Lichtbildflugzeug (photo aircraft) in acknowledgement of their primary role.
   Regardless of designation, if the pilot maintained maximum altitude the Rumplers were almost impossible to intercept during their missions.
   Lichtbildflugzeug (photographic aircraft) were specialized high-altitude aircraft used for long- range photo-reconnaissance. The only operational types were the Rumpler Rubild and Rubild Mb. Both were based on the Rumpler C.IV airframe equipped with a Messter strip camera and greater fuel capacity. The Rubild, powered by the 260 hp Mercedes D.IVa, was originally designated the Rumpler C.VI. The Rubild Mb was the same aircraft except with the 245 hp Maybach Mb.IVa engine.

J.Herris Rumpler Aircraft of WWI (A Centennial Perspective on Great War Airplanes 11)

Rumpler Aircraft Using the C.IV Airframe
Designation Engine Notes
Rumpler C.VII 245 hp Maybach Mb.IVa
Rubild Mb 245 hp Maybach Mb.IVa Rubild equipped with Maybach engine

M.Dusing German Aviation Industry in WWI. Volume 2 (A Centennial Perspective on Great War Airplanes 85)

Rumpler-Werke A.G. in Berlin-Johannisthal (Ru)

Aircraft Development:

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  Particularly appreciated at the front were the long-range reconnaissance aircraft of Rumpler-Werke (Rubild). These aircraft could quickly gain 6000 to 7000 meters in altitude and effectively enable reconnaissance of the war zone.
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