Junkers Flugzeug-Werke AG

Junkers J.I (2nd series) Unit: Flieger-Abteilung (A) 290 Serial: J.838/17 Courbes, France, August 1918.

Junkers CL.I Unit: Kampfgeschwader Sachsenberg Winter 1918-1919. Sachsenberg was a Navy ace pilot. He was a commander of this unit. His unit was a part of German Voluntary Corps which was created in 1919 of German Occupation troops in Baltic. Note: camouflage spots’ location is probable.

The Junkers Aircraft Company started life not as an aircraft manufacturer, but as a manufacturer of gas water heaters for bathtubs, industrial boilers and temperature gauges. Dr Hugo Junkers was one of the most innovative engineers of his time, and, during his lifetime, was awarded more than 1,000 patents covering an extremely wide variety of fields.

His first real introduction to the world of aviation was in 1909. He was a professor at Aachen Technical High School when a fellow professor invited him to collaborate on an aircraft project. Hugo Junkers had been studying aerodynamics while at the school and built a wind tunnel. He became more and more interested and finally decided to embark on a career in aviation at the age of fifty.

Hugo Junkers had for some years been looking at the concept of producing an all-metal monoplane aircraft, and at the beginning of December 1915 the Junkers J.1, also known as the E.I, appeared. The first test flight, carried out on 12 December by Leutnant Friedrich Mallinckrodt at Döberitz, was a resounding success. The thin sheet-metal covering the aircraft gave rise to the name ‘Tin Donkey’. Powered by a 120-hp Mercedes D.II engine, the J.1 had a top speed of 100 mph, which was somewhat slower than the streamlined appearance indicated. It was this that probably gave the aircraft the additional name of ‘Donkey’.

The J.1 had a wingspan of 42 ft 5½ in, a fuselage length of 24 ft 4½ in and a height of 10 ft 3 in. Only one of the aircraft was built, but it was enough to impress the Flugzeugmeisterei (Air Ministry) who asked Hugo Junkers to produce an armoured biplane.

In the meantime, a second all-metal monoplane was built in 1916, the Junkers J.2, also known as the E.I. Only six of these aircraft were built and they were powered by a 120-hp Mercedes D.II engine, which gave the aircraft a top speed of 90∙mph. The sixth model was fitted with the more powerful 160-hp Mercedes D.III engine, but the performance differential was little. The J.2 had a wingspan of 36 ft 1 in, a fuselage length of 23 ft 11½ in and a height of 10 ft 3 in.

At the end of 1916, together with Professor Madelung, Hugo Junkers designed an armoured biplane that was to be covered in a corrugated metal sheet that was riveted to the duraluminium framework of the Junkers J.1. The factory designation of this aircraft was J.4, but the military designation has always been given as the J.1. This has given rise to confusion in the past when the J.1 has been discussed.

The first J.1 (J.4) models had a hexagonal-shaped fuselage. The nose section, which enclosed the engine and cockpits, was armoured and made of 5-mm chrome-nickel sheet. This section was then joined to the rear fabric-covered part of the fuselage; the tailplane and elevators were of standard construction. Later models of this aircraft had the corrugated metal skin covering the entire fuselage.

The J.1 (J.4) was powered by a six-cylinder, in-line, water-cooled 200-hp Benz Bz.IV engine with a rhino horn-type exhaust, that gave the aircraft a top speed of 96 mph and an endurance of two hours. It was armed with two synchronised forward-firing, fixed Spandau machine guns and One manually operated Parabellum machine gun mounted in the rear cockpit.

The Junkers J.1 (J.4) had an upper wingspan of 52 ft 6 in, a lower wingspan of 38 ft 9 in, a fuselage length of 29 ft 10½ in and a height of 11 ft 1½ in. In total, 227 Junkers J.1s (J.4) were built, the first of them arriving at Flieger-Abteilung (Inf) units at the end of 1917. The crews found the aircraft difficult and extremely cumbersome during landings and take-offs, because of the weight of the armour plating. This, however, was weighed against the extra protection that the armour plating offered, which more than compensated for the other problems. The J.1 (J.4) was used extensively for low-level reconnaissance missions and ammunition and ration supply drops to front-line troops.

Encouraged by the acceptance of his aircraft by aircrews, Hugo Junkers started on perhaps the most ambitious project of his First World War aeronautical career, the Junkers R.I. Powered by four 260-hp Mercedes D.IVa engines that turned two propellers of 16 ft 5 in diameter, the projected speed of the aircraft was 112 mph. Projected is the operative word, as although two models, the R.I and the R-plane project were ordered by Idflieg, none were ever actually constructed.

A great deal of experimentation using wind tunnels was carried out, but the project was so huge that even when the Fokker Company was ordered to merge with Junkers, progress was extremely slow. This was mainly due to the fact that Anthony Fokker was used to making wooden aircraft and in mass production, while Junkers made all-metal aircraft, which for obvious reasons took longer to construct. In addition, the two parties were not personally compatible. The Armistice put paid to any more progress and the parts that had been assembled were destroyed.

While the development work was being carried out on the R.I projects, work continued on producing the smaller J models. The J.3 was scheduled to be the first to be completely covered in the corrugated metal, but for some unknown reason the airframe was never completed. However, several experiments were carried out after a number of misgivings had been expressed regarding the safety of an all-metal cantilever wing. In order to dispel any fears, Junkers had forty-two of their workers stand on an unsupported J.3 wing. The experiment was a complete success and work continued on the production of the wing without any more concerns being expressed.

There was no J.4, J.5 or J.6, but the J.7 was built at the beginning of 1917. The J.7 was the prototype for the J.9 or D.I model that went into production at the beginning of 1918.

Still continuing with the monoplane theme, the J.7 was the subject of a number of variants, some with ailerons, and some without. Powered by a 160-hp Mercedes D.III engine with a car-type radiator at the nose, the J.7 had a top speed of 105 mph.

A matter of months later, the Junkers J.8 appeared. This all-metal aircraft was a two-seat prototype of what was to ultimately be the one of the mainstays of the Schlachtstaffeln, the J.10 (CL.I). It was powered by a 180-hp Mercedes D.IIIa engine, which gave it a top speed of 100 mph and a climb rate of almost 1,000 feet per minute. It had a wingspan of 39 ft 6 in, a fuselage length of 25 ft 11 in, and a height of 7 ft 8½ in. It was armed with twin synchronized fixed Spandau machine guns and One manually operated Parabellum machine gun mounted in the rear cockpit. In total, forty-seven Junkers J.10s were built and all were in action right up until the end of the war.

The German Navy, impressed with the J.10, requested a seaplane version. Three were converted and given the designation J.11 (CLS.I). It was almost identical to the J.10 with the exception of an additional fin fitted on the fuselage in front of the tailplane and, of course, the addition of floats instead of an undercarriage. It was powered by a 200-hp Benz engine, which gave the aircraft a top speed of 112 mph. It had a wingspan of 41 ft 10 in, a fuselage length of 29 ft 4½ in, and a height of 9 ft 8 in. Its armament was the same as that of the J.10.

Although Junkers’ contribution to First World War aviation was not as great as some of the other aircraft manufacturers, they became one of the most prominent elements some years later when the two warring factions were once again at each other’s throats.