В.Кондратьев Самолеты первой мировой войны

Румплер C-III / RUMPLER C-III

   Дальнейшим развитием удачной машины стал C-III - самолет с улучшенной аэродинамикой, более мощным мотором, синхронным пулеметом "Шпандау" и бомбовой кассетой в фюзеляже. Это был в самом широком смысле слова универсальный аппарат, способный выступать во всех ролях, от бомбардировщика до перехватчика.
   "Троек" построили довольно мало - всего 75 штук, так как уже в конце 1916-го появился еще более усовершенствованный образец - C-IV.
  
  
ДВИГАТЕЛЬ
  
   "Бенц", 220 л.с.
  
  
ВООРУЖЕНИЕ
  
   1 синхронный "Шпандау" и 1 турельный "Парабелум", а также - до 100 кг бомб.

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

Rumpler C III (6A 5)
   Appearing in 1916, the Rumpler C III differed little from the C IV, into which it was developed. It was chiefly distinguished by the comma rudder and the large angular balances on the ailerons. The decking aft of the rear cockpit had a peculiar compound curvature, but this was later modified to an orthodox decking and the designation 6A 6 allocated. Engine, 220 h.p. Benz Bz IV. Span, 12.66 m. (41 ft. 6 1/2 in.). Weights: Empty 953 kg. (2,097 lb.). Loaded, 1.470 kg. (3,234 lb.).

  
Rumpler C V
   This type was virtually a C III (6A 5) airframe fitted with a 260 h.p Mercedes D IVa engine. Apart from the tail surfaces, construction was identical to the C IV. Armament, one Spandau and one Parabellum machine-guns.

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

Rumpler C.III

   The Rumpler C.III (6A5) was a transitional production type between the better-known and more successful C.I and C.IV two-seaters. The Rumpler C.I, powered by the 160 hp Mercedes D.III engine, entered service in 1915 and was an immediate success. It was kept in production for the remainder of the war, initially as a combat aircraft, later as a trainer due to its excellent handling characteristics. Rumpler C.II was the designation reserved for a production version of the Rumpler 5A3 prototype, which was basically a modified C.I powered by a 180 hp Argus As.III engine. However, only one prototype was built and the C.II did not go into production. Further Rumpler two-seater development through a series of prototypes lead to the Rumpler C.III.
   Whereas the C.I was a general-purpose observation plane, the C.III was intended as a higher performance aircraft for high-altitude photographic reconnaissance. The basic struture of the C.III remained similar to the C.I, being a conventional wood frame covered in fabric. However, the aerodynamic design, wing planform, and airfoil section were all changed to provide better high-altitude performance. Development of the new wing cellule paced the C.III design.
   The C.III was powered by the 200/220 hp Benz Bz.IV engine, providing it with substantially more power than the C.I, again to improve speed, climb, and ceiling. In addition to the more powerful engine, the nose entry was more streamlined for lower drag, and included a large propeller spinner. The prototype featured air intakes under the nose, but these were omitted in the production aircraft.
   Unlike the earlier C.I, which had a fixed fin, unbalanced control surfaces, and good handling qualities, the prototype C.III was built with all control surfaces aerodynamically balanced to reduce control forces. To minimize weight and drag for maximum performance, the prototype C.III omitted a fixed vertical fin, something tried by many German designers. However, few designs without a fixed fin were successful due to inadequate directional stability, and the C.III was no exception. During its production run the C.III was subject to continuing revision to its control surfaces to improve its flying qualities. Like the prototype, all control surfaces on early production C.III aircraft were aerodynamically-balanced, and there was no fixed fin. Mid-production C.III aircraft changed to a fixed fin and unbalanced rudder to improve flying qualities. The ailerons were revised at the same time, when C.III aircraft were fitted with a fixed fin the ailerons were changed to unbalanced. Initially the balanced elevators were retained. The final production C.III aircraft eliminated the elevator balances to further improve flying qualities. There are several photos of crashed early configuration C.III aircraft after control problems, indicating the C.III control changes were necessary.
   The C.III was fitted with the standard C-type armament, a fixed, synchronized gun for the pilot and a flexible gun for the observer. To make the type more versatile, a small bomb bay was built into the starboard side of the observer's cockpit. The prototype C.III had an unusually shaped turtledeck behind the observer's cockpit; this may have obstructed the observer's field of fire and was replaced in production aircraft by a conventional turtledeck.
   The Rumpler C.III first appeared at the front at the end of 1916, and by the end of February 1917 42 were at the front. Although the C.III had better performance than the C.I, its handling characteristics were less pleasant and the control modifications mentioned above had to be introduced on the production line. Within two months the number of C.III aircraft at the front dropped to 22 as the C.III was quickly replaced by the more powerful Rumpler C.IV, and by the Autumn of 1917 the C.III had virtually disappeared from the front. Unlike the viceless C.I, the C.III did not go on to an extensive career as a trainer.

Production and Service

   The Rumpler C.III was built in small numbers. In July 1916 150 aircraft were ordered, but only 49 were built with serials 1863/16 to 1911/16. Serial 1912/16 was the prototype C.IV. The other 100 aircraft from that order may have been changed to the C.IV. From photographic evidence the transition from the early configuration (no fixed fin, all controls balanced) to the final configuration (fixed fin, all control surfaces unbalanced) took place at some point between serials 1869/16 and 1898/16 (although 1903/16 retained the balanced elevators of the mid-production configuration; apparently serial numbers were not always assigned in production order).
   Only one C.III was at the front at the end of 1916, but two months later the inventory had jumped to 42. Thereafter C.III numbers at the front went into rapid decline as the more powerful Rumpler C.IV, which possessed significantly better performance, replaced it. The Rumpler C.IV quickly gained a reputation as the best German long-range reconnaissance aircraft, a reputation the C.IV and its derivatives retained throughout the war. All the Rubild Rumplers used the C.IV airframe, which was essentially the final production C.III airframe with unbalanced control surfaces.

In Retrospect

   Development of the Rumpler C.III, especially the wing cellule, to achieve the best high-altitude performance was challenging. Handling and structural problems plagued production C.III aircraft, requiring a series of revisions to its control surfaces during production. Moreover, a more powerful engine than the 200/220 hp Benz Bz.IV was needed to achieve the airframe's full potential.
   Thus from an operational perspective, the Rumpler C.III was, at best, a marginal success.
   However, from a development perspective, the C.III was a great success. It was the operational testbed for the airframe that, once developed, lead to the legendary C.IV and its related family of aircraft.
   The Rumpler C.III was thus a transitional design between the highly-regarded, easy to fly general-purpose C.I and the high-performance C.IV. Although the C.III served at the front in modest numbers, its most significant role was that it introduced and refined the basic airframe used by the more powerful C.IV and its family of derivatives, which were the best German long-range reconnaissance aircraft of the war.

Rumpler C.III Specifications
Engine: 200/220 hp Benz Bz.IV
Wing: Span 12.66 m
Area 34.8 m2
General: Length 8.20 m
Empty Weight 839 kg
Crew 160 kg
Fuel 105 kg
Military Load 164 kg
Useful Load 520 kg
Loaded Weight 1,264 kg
Maximum Speed (at 2,000 m): 136 kmh
Climb: 2000m 16 min
Service Ceiling: 4000m
Range: 480 km