It was a complete new original design by Roland. When manufacturing the Albatross B.II and C.I under license, Roland engineers were concerned about the high amount of drag created by the amount of bracing wires present in those designs. Roland engineers sought for a way to reduce it and to increase speed employing only the same engines currently in service. Priority was also given to the observer, as he had to have a wide field of fire. This design work, eventually led to the Roland C.II Walfisch (German word for 'Whale').
The Roland C.II was designed mostly by Prof. Ludwig Prandtl at the Göttingen University's wind tunnel. The C.II combined new construction techniques with superior aerodynamics to achieve the desired increase in performance. For this aircraft Roland engineers employed the Wickelrumpf technology which was about combining layers of veneer strips wrapped diagonally around a mold at an angle to each other and glued and reinforced with fabric. This method resulted in a robust and streamlined fuselage which could carry the structural loads.
The first prototype was flight-tested on 24th or 25th October 1915 and was powered by a single Mercedes D.III engine which could yield 160 hp of power. Unfortunately, the engine failed short after take-off, damaging the prototype, which had to be repaired. During speed trials it shown a considerable speed advantage of around 30 km/h (19 mph) faster over contemporary German two-seaters, so the Fliegertruppen (Imperial German Army Air Corps) placed a production order for 50 aircraft on 23rd December 1915.
Further testing made in February 1916, showed that the wing cellule was not strong enough, so an additional drag wire had to be installed. This setback delayed the initial production run until 7th March 1916, when the first five production aircraft left the Luft-Fahrzeug-Gesellschaft (LFG) factory, which was the firm granted with the mass-production license of the type.
The production version of the C.II arrived at the frontlines in March 1916, and was very liked by pilots and crews, and it served until June 1917. It was the smallest and fastest German two-seater which, thanks to its aerodynamic shape and the Mercedes D.III engine, had an excellent performance for the time. It could match the French Nieuport 17 and the British Sopwith Pup fighters in speed, making it an effective combat aircraft. This speed forced the C.II to operate together in groups of other Roland C.IIs to avoid being slowed down by their slower contemporaries.
However, speed, as important it may be, it is not everything in aerial warfare and the Roland C.II's flight characteristics needed improvement. The most important setback for the C.II was the limited forward and downward visibility the pilot had, making it hard and tricky to land, for which roll bars were added in the pilot's cockpit.
Anyway, although landing accidents were very common in World War I aircraft, in comparison, the C.II proportionately much less than its contemporaries.
Anyway, although landing accidents were very common in World War I aircraft, in comparison, the C.II proportionately much less than its contemporaries.
In order to improve combat effectiveness, a fixed and synchronised forward-firing machine gun was included for the pilot in the second production batch. This inclusion forced a redesign of the roll-over structure to accommodate the Maschinengewehr 08 machine gun. Additional changes were also made on-the-way during third production batch's manufacturing process to improve flight characteristics. These included moving the interplane I-struts inboard and reducing slightly the wing span, in order to strengthen the wing. This modified variant was called "Roland C.IIa" and it was static-tested in later April and early May 1916. This variant reached the frontlines in the summer of 1916.
The C.IIa also featured an enlarged vertical tail to improve flight stability and control. This feature was made common to the fourth and last batch of 40 aircraft, ordered in June 1916.
This improvement was much needed for the C.II and it should've been made before the C.II was produced en masse.
The German firm Linke-Hoffman was granted a manufacturing license in July 1916 and another one of 40 in September. These machines were denominated as Roland C.IIa(Li). The type tests of this new batch took place in November 1916 and they reached the frontlines in early 1917. However, by that time, new and better German and Allied aircraft were present at the frontlines and the C.II had lost its performance advantage, cutting short its operational history. After being withdrawn from the frontlines, the C.II served with various flight schools until 1918.
Sources:
1st Aeronaut Books - Great War Aviation Centennial 9 - Roland Aircraft of WWI
2nd https://en.wikipedia.org/wiki/LFG_Roland_C.II
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