Mercur-Flugzeugbau GmbH, Berlin-Neukolln (Merc)

Foundation:

  The company was founded on April 15, 1915, under the above name by Romeo Wankmuller (owner), Hermann Tradowsky (managing director) and Mr. Tiege. As a subsidiary with foundation date March 7,1917, the “Mercur-Motorenbau GmbH” was established, which was engaged in trials of an engine designed by the company itself.


Aircraft Development:

  In parallel with the orders for new Alb B.II and Alb C.Ib aircraft already mentioned above, the company attempted to bring out a fighter aircraft as its own design as early as the summer of 1917, which made it as far as its test flights, but was not satisfactory overall. As a result of this failure, the company started to design a “Type CL” aircraft, the development of which could not be completed by the end of the war, despite good flight characteristics.
  The experimental department of the Mercur factory was quite active. The following projects were pursued:
  1. Fighter single-seater (Kampf-Einsitzer) KE 2, The aircraft was brought to Johannisthal for flight testing in March 1918. However, necessary modifications prevented successful flight testing.
  2. Aircraft torpedo.The project, detailed designs, and detailed description were submitted to the Idflieg. The fuselage and wings were completed, but the project was not finished.
  3. Light fighter CL.II.The project and complete construction drawings were completed, as was prototype construction. The required supercharged 200 hp Benz Bz.IVu engine had been available since April 1918. It is not known whether flight testing took place.
  4. Fighter single-seater Type D (biplane) Prototype construction was started. Nothing is known about the completion or the beginning of a flight test.
  5. Single-seater KE 3 (monoplane) Such a project was started, but not completed.
  6. Single-seater KE 4 (monoplane with rotary engine). Such a project was in the planning stage.
  7. Giant airplane. This 1918 project of a giant airplane was to be equipped with four 260 hp Mercedes D.IVa engines. Six machine guns and 2,000 bombs were to be carried on board
  8. Tachometer: Mercur Kinergometer
  9. Mercur engine (Mercus-Motorenbau GmbH). This 350 hp stationary engine was about to be tested at the end of the war. As a result of the construction restrictions imposed by the Treaty of Versailles, further development of this powerful engine had to be discontinued after the war. Only the Mercur KE 2 and CL.II projects were realized.
  But there was no time to finish the aircraft, and under surrender conditions the prototype KE 2 and CL 2 fighters were destroyed in May 1920.
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Max Oertz, Jachtwerft, Neuhof-Reiherstieg (Hamburg)
  
Foundation:

  Max Oertz, a builder of high-quality sailing yachts, began designing aircraft in 1909. Later he took over the contract manufacturing of some Wright biplanes for the Berlin company, which in return provided the distribution of the monoplane designed by Oertz.
  Max Oertz designed his first powered aircraft as early as 1909, and the first closed aerodynamic fuselage in 1911. Max Oertz designed several flying boats for the Navy and maintained his own airfield in Schneverdingen for test flights. Most of the known aircraft were flying boats, of which the Oertz W6 Flugschoner was particularly striking, a tandem biplane with an additional conventional tailplane and double rudder. The two Maybach engines were housed in the elegant boat hull and drove the propellers via long-distance shafts. Prince Heinrich of Prussia supported him, and the Reichs-Marine-Amt (RMA) also took over some flying boats.
  But around 1917, the company was incorporated into the “Hansa-Brandenburg” company.


Aircraft Development:

  Max Oertz’ designs also included aircraft and self-stabilizing captive balloons. For the Zeppelin, Oertz designed a so-called spotting basket, which could be roped down from the military airship sailing above the clouds on a long rope to below the cloud cover for observation purposes.
  From “Flugsport 1979”: Above all, the Oertz Works were not laid out as quantity production works but were used to meet the special requirements of yacht construction by scientific investigation into the smallest mechanical details, and to devote an absolutely loving care to workmanship and finish.
  These fundamental facts, which were reflected in all new productions of this scientifically working factory, whether boats or flying machines, could already be noticed in the very first machine built in 1910. This was a land machine, a monoplane with monocoque body, which weighed only 770 lbs., and, fitted with a 70 hp Gnome engine, reached a speed of 80 m.p.h.
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Pfalz Flugzeug-Werke GmbH

Foundation:

  The company was founded in July 12, 1913 by Mr. Alfred Eversbusch. Since the financial means of one individual were not large enough for such an undertaking, not only the whole Eversbusch family participated. That is, in addition to Alfred Eversbusch, his brother Ernst and his brother-in-law Willy Sabersky-Mussigbrodt, there were three other shareholders: the brothers Richard and Eugen Kahn and August Kahn, who was not directly related to the brothers.
  Pfalz Flugzeugwerke GmbH was thus one of the oldest German aircraft manufacturing companies and during World War I became the third largest manufacturer of fighter aircraft in Germany after Fokker and Albatros.
  Apparently for economic reasons, the company was geared up to build under license. Willy Sabersky-Mussigbrodt, who was the only person with technical training in the field of aircraft, had already joined another company as a designer in 1914. In order to obtain a license contract, Alfred Eversbusch turned to the Albatroswerke in Berlin-Johannisthal. But there they were only interested in granting a license if they could acquire a share in the Pfalz-Flugzeugwerke. Therefore, a contract was signed to establish a new company: Pfalz-Flugzeugwerke Licenz Albatros GmbH. But real activities of this new company never took place. For as early as August 5, 1913, Albatros GmbH applied for cancellation of its registration.
  After some legal wrangling, the cancellation of the application was granted in December 1913 and the company was again registered as Pfalz-Flugzeugwerke GmbH.
  Before the war, it had acquired a license from the French company Morane-Saulnier. During the war, it was given the short name "Pfal" by the Flugzeugmeisterei.


Aircraft Development:

  Initially, an agreement was reached with the Bavarian Otto-Werke to build its types under license. After delivery of the promised type, production of the first licensed aircraft began immediately by the Pfalz-Flugzeugwerke at the Speyer Festhalle. Alongside this, used Otto biplanes were also repaired.
  By the outbreak of war, the company had produced just three Parasols, with three more Otto biplanes under construction for the Royal Bavarian Flying Forces. From August 1914 to the end of 1916, Parasol two-seaters and Morane-Saulnier single-seaters with 80 and 100 hp (known as Pfalz E.I and E.II), the latter later also with 160 hp (Pfalz E IV) Oberursel Gnome engines were built, following French designs. Parasol were without, the Morane already equipped with one or two turnable machine guns.
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  In the case of the Parasol aircraft, the advantage was the relatively short takeoff and landing distance of about 50 m with a payload of 230 kg, and these aircraft could climb to 2,000 m within 16 to 18 minutes. The 60 Parasol aircraft were delivered without exception to the Bavarian Army Administration (Fea lb, Schleifiheim).
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Rumpler-Werke A.G. in Berlin-Johannisthal (Ru)

  In 1908, a small office and workshop were set up in Berlin on Gitschiner Strasse, where design parts for automobiles and aircraft were built; it was later moved to Reinickendorfer Strasse. In this office, among other things, the basic principles for the aircraft engine Aeolus were developed.
  Rumpler-Werke is the oldest aircraft factory in Germany after Euler-Werke. The first German aircraft factory had been founded a month earlier in October 1908 by August Euler in Frankfurt am Main.
  On November 24,1908, the "B.Z. am Mittag" published the following announcement:
  "Engineer Edmund Rumpler, Berlin SW, Gitschiner Strasse 5, has incorporated an aircraft construction institute (Luftfahrzeugbauanstalt) into his technical office. The company does not intend to manufacture specific types of aircraft, but rather to implement promising ideas in an appropriate manner at moderate prices. Small aircraft models are also to be manufactured there." Thus the company "Edmund Rumpler, Luftfahrzeugbau" was born. At first it was only a small department, which was attached to the already existing engineering office.
  Thus, in the founding period of the company, the main focus was initially on the advisory and expert evaluation of the countless existing ideas and conceptions in aircraft construction. The business idea led quite quickly to success. Engineer Rumpler, who had previously worked in automotive engineering at Daimler and Adler, where he designed the Adler engine and the Adler motor car, quickly made a respected name for himself.
  In 1909, particularly as a result of the heavy workload in the aircraft department, E. Rumpler saw fit to transform the company into a "Rumpler-Luftfahrzeugbau GmbH" with 90,000 Marks in capital and at the same time to move the factory to Lichtenberg. Gradually, the capital was increased to 700,000 Marks.
  In 1910, Rumpler rented a hangar in Johannisthal on the northern border of the airfield to have the opportunity to test flying machines on the airfield.
  In July 1915, Rumpler-Werke was renamed "Rumpler-Werke GmbH". After the GmbH was dissolved in September 1917 and registered as "E. Rumpler Luftfahrzeugbau in Liqu.", Rumpler-Werke transformed into a stock corporation (equity capital: 3.5 million Marks) as of January 1, 1918.


Aircraft Development:

  The origin of the Rumpler-Taube, whose construction period fell between October 1910 and December 1912, can be traced back to the research work of the Hamburg professor Ahlborn. Ahlborn pointed out to Rumpler that the Austrians Weis, Hiner and Etrich were already working on an aircraft project whose wings were being manufactured on the basis of his information concerning the stabilizing properties of the Zanonia seed. Shortly after, Rumpler-Werke signed a license agreement with Etrich. Shortly thereafter, however, it became apparent that, despite the correct basic principle, improvements were needed in many areas. As a result, various "Tauben" were built, powered by 50-70 and 100 hp Gnome, 70, 100 and 120 hp Argus, 70 and 120 hp Austro-Daimler, 70 and 100 hp Daimler-Mercedes, 80 hp Hiero (Werner and Pfleiderer), 70 hp Dixi (Fahrzeugwerk Eisenach), 50 hp Antoinette, 95 hp NAG as well as 70 hp Daimler with hanging cylinders and 50 hp V8 Rumpler-Aeolus engine.
  Although the company began building seaplanes in 1911, it was not until 1913 that it built the seaplane station at Muggelsee in Berlin-Kopenick.
  The outstanding personality from an aviation point of view in the 2nd decade of the 20th century was Rumpler's chief pilot Hellmuth Hirth.
  With Hirth at the top, Rumplers flight school progressed and became one of the most successful institutions in flight training. Hirth achieved lasting fame by flying from Munich to Berlin in June 1911 on a Rumpler-Taube. In 1912, Hirth was the star of almost every large flight competition and with that became the most successful and renowned aviator from Johannisthal. He changed employers in early 1913 and then became the chief technology officer of the Albatros-Works, also at Johannisthal.
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Sablatnig-Flugzeugbau-Gesellschaft m.b.H., Berlin (Sab)

Foundation:

  Josef Sablatnig initially studied mechanical engineering at the Technical University in Graz and electrical engineering at the Technical University in Brno. When the technophile Sablatnig heard about the successful flights of the Wright brothers, he left Europe and went to the USA for some time to study with the Wrights. Before returning to Germany in 1910, Sablatnig bought a Wright airplane that same year. In 1911, he became a naturalized Prussian citizen. In the same year he took up employment with Louis Bleriot and then in Wiener Neustadt with the Autoplan company, where Sablatnig met the Munich engineer Karl Bomhard.
  In May of the same year, Bomhard applied for a patent on a biplane with sweep and V-shape. He was also involved in the development of a monoplane called "Monobiplan". However, he lacked any flying experience. In 1911/12, he had a biplane built at Goetze-Flugzeugwerke. A second biplane was commissioned from Lohner, which was based on the proven model of the Lohner-Pfeil biplane. This Lohner-Bomhard biplane achieved remarkable feats in 1912 - an altitude of 850 meters.
  1912 was also the year in which Bomhard returned to Germany and met Josef Sablatnig. The latter further developed the "Bomhard arrow biplane", which was built by the Berlin coachbuilding company Kuhlstein.
  Sablatnig was a founding member of Union-Flugzeugwerke in 1913, where the first Bomhard biplanes were also mass-produced.
  During the First World War, he was involved in building up the naval air force as a war volunteer in Kiel. On October 5, 1915, Dr. Josef Sablatnig and the banker Josef Mollinger founded their own aircraft design company, the "Sablatnig-Flugzeugbau GmbH", which, among other things, designed and built the types Sablatnig SF 2, SF 5 and SF 6 in small series from 1916 onwards in the premises acquired from the Goetze Flugzeugwerke. Since the small company was overwhelmed by production orders, it was supported in this by Luftfahrzeug-Gesellschaft mbH (LFG, Roland).
  The military abbreviation was "Sab".


Aircraft Development:

  During World War I, as a war volunteer under Prince Heinrich of Prussia in Kiel, he was involved in building up the German naval air force. The first naval aircraft designed by Sablatnig, SF 1, registration 490, was built in Berlin in the workshop of the boat builder Rethel. The necessary steel parts were supplied by the Gotze company. Sablatnig presented this aircraft to the Navy administration in the summer of 1915 and hoped for a positive evaluation, since the performances presented certainly gave cause for acceptance of this aircraft as a new naval aviator type.
  Sablatnig, without having already opened his own aircraft manufacturing company, received an order to build 16 aircraft, a significant number for the Navy at that time. In the absence of his own workshops, Sablatnig agreed with Dr. Gotze to have the naval reconnaissance planes built under the designation SF 2, in the latter's aircraft works. The aircraft were delivered in the summer of 1916.
  When the Reichs-Marine-Amt held out the prospect of a follow-up order for 30 to 40 aircraft, Dr. Sablatnig and banker Moiling set up Sablatnig-Flugzeugbau-Gesellschaft mbH, Berlin, at the beginning of October 1916 by purchasing Department III of the Gotze Company at Schlesische Str. 26.
  Subsequently, they created the Sablatnig SF 2, SF 5, SF 6, and SF 8 types, which were built in small series. Greater success was achieved with the SF 5, a direct development of the SF 2, of which 101 aircraft were delivered. However, since the small company was overwhelmed by production orders, it was supported by Luftfahrzeug-Gesellschaft mbH (LFG) and Luft-Verkehrs-Gesellschaft (LVG) by acting as licensees. Sablatnig built the FF 49c under license for Flugzeugbau Friedrichshafen.
  In 1917, construction of landplanes began after an SF5 was fitted with a wheeled landing gear instead of floats for experimental purposes and successfully tested.

Luftfahrzeugbau Schutte-Lanz, Zeesen (SchuI)

  Johann Schutte (1873-1940). Mr. Geh. Kommerzienrat von Rochling and the well-known agricultural machinery builder Karl Lanz and his wife founded the company Schfitte-Lanz-Luftfahrzeugbau GmbH in Mannheim on June 1,1909 and built the Schutte-Lanz airship for World War I starting in 1911. As the second largest airship manufacturer, the company was Graf Zeppelin's main competitor. Schutte's rigid airship differed from the Zeppelin type in its wooden frame. On October 17, 1911 the first test flight of the airship SL I started in Rheinau.
  At the beginning of the last year of the war in 1918, the company was transformed into a general partnership under the name "Luftfahrzeugbau Schutte-Lanz oHG".
  During the war, it had a second factory built in Zeesen for fear of air raids. Construction of this factory began on October 1, 1915.


Luftfahrzeugbau Schutte-Lanz, Mannheim-Rheinau (Schul)

  Initially, the aircraft company did not have its own factory premises in Mannheim. It was affiliated with the parent company "Heinrich Lanz, Mannheim", which had a total site of around 842,000 m2 and an airfield of just under 650,000 m2.
  The airship company was located in the middle of the Rhine plain, in the southeast of the city of Mannheim, 9 km from Mannheim's main train station, near the Mannheim-Karlsruhe railroad line. A branch fine Rheinau-Ketsch branched off from the Rheinau station of this railroad fine, which could also be reached from Mannheim by electric streetcar in about 30 minutes, and its first station, "Luftschiffwerft", was located on the factory premises.
  The company was originally engaged in the construction of Schutte-Lanz type airships and later moved on to supplying aircraft spare parts specifically for DFW and AGO as well as repairing aircraft. New aircraft construction, especially in Zeesen, was not started until 1917. From the beginning of 1918, the Mannheim plant supplied apparatus for engine installations and bombing.


Aircraft development:

  The Mannheim plant did not carry out its own aeronautical development, as all development work was transferred to the Zeesen plant. As mentioned, in Mannheim-Rheinau, they were busy with the production of spare parts for airplanes and occasional repairs of airplanes. The Schutte-Lanz factory, manufactured:
   18 airships;
   1 experimental aircraft, C-Typ;
   2.300 valves for balloons;
   9,000 sets of radiator valves for aircraft.
  Luftfahrzeugbau Schutte-Lanz in Mannheim-Rheinau repaired: 5.271 aircraft and 113 engines.

Luftfahrzeugbau Schutte-Lanz, Zeesen (SchuI)

  Johann Schutte (1873-1940). Mr. Geh. Kommerzienrat von Rochling and the well-known agricultural machinery builder Karl Lanz and his wife founded the company Schfitte-Lanz-Luftfahrzeugbau GmbH in Mannheim on June 1,1909 and built the Schutte-Lanz airship for World War I starting in 1911. As the second largest airship manufacturer, the company was Graf Zeppelin's main competitor. Schutte's rigid airship differed from the Zeppelin type in its wooden frame. On October 17, 1911 the first test flight of the airship SL I started in Rheinau.
  At the beginning of the last year of the war in 1918, the company was transformed into a general partnership under the name "Luftfahrzeugbau Schutte-Lanz oHG".
  During the war, it had a second factory built in Zeesen for fear of air raids. Construction of this factory began on October 1, 1915.


Luftfahrzeugbau Schutte-Lanz, Werk Zeesen/Konigs Wusterhausen i. Mark

Aircraft Development:

  Shortly before the war, Schutte-Lanz had already been engaged in the construction of airplanes. In the course of 1915, the G airplane with two engines arranged on the wings was completed. During a test flight, however, this prototype suffered a total loss. Since at that time the military authorities still gave priority to the airship, they showed no interest in such a large aircraft. As a result, further developments were initially discontinued. In the meantime, work began on October 1, 1915 on the construction of a new shipyard in Zeesen near Konigs Wusterhausen. Construction of the first airship manufactured in Zeesen could begin here as early as the early summer of 1916. In order to achieve an effective utilization of the shipyard, the board of Schutte-Lanz AG decided to locate the experimental aircraft construction in Zeesen as well. Thus, in addition to the airship hangar, various workshops for aircraft construction were built at the shipyard.
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Siemens-Schuckert-Werke, Abt. Flugzeugbau, Siemensstadt b. Berlin (SSW)

Foundation and Start of Aircraft Production:

  Before the war, Siemens-Schuckert-Werke (SSW) manufactured mainly electrical machines and electrical equipment at several locations in Germany. In the course of the war, it also engaged in aviation.
  Siemens-Schuckert-Werke had begun building a semi-rigid airship in 1907 when the commander of the Prussian Airship Battalion, Major Groll, presented it with a design he had worked out together with Chief Engineer Basenach and Captain Sperling. This military airship had a gas capacity of 1800 m3, was 40 m long, and had a 25 hp engine. After several successful voyages in the winter of 1908/9, the larger airship M I with a gas capacity of 5,000 m3 followed. SSW then started to build its own airship, designed by Dr. Kreil and Dipl.-Ing. Alexander Dietzius. With a gas capacity of 13,000 m3 and a length of 118 m, it was the largest semi-rigid airship and was powered by 4 x 125 hp Daimler engines. The first voyage took place on January 23, 1911, and it was later stationed in the newly built revolving hangar in Biesdorf, east of Berlin. A total of 72 trips were made, and while the airship proved to be quite fast, its dimensions proved too large for an impact airship. Airship construction was subsequently abandoned at SSW.
  Parallel to these airship tests, aircraft construction was also carried out from 1909 onwards, under the direction of Mr. Burkhardt, who with a further 2 occupants undertook tests with a biplane manufactured by SSW, but crashed with this aircraft in 1911, with the flying machine suffering a total loss.
  The Siemens-Schuckert-Werke in Nuremberg, a branch of the Siemens-Schuckert-Werke, Siemensstadt, started aircraft construction in January 1916 and incorporated it into the transformer plant.


Aircraft Development:

Siemensstadt:

  The practical implementation of aircraft construction began in 1909 in a small workshop on the Bornstedter Feld near Potsdam, where engineer Burkhardt designed a biplane.
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Siemens-Schuckert-Werke, Abt. Flugzeugbau, Siemensstadt b. Berlin (SSW)

Aircraft Development:

Siemensstadt:

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  Siemens-Schuckert-Werke achieved its first major successes with the development of a single-seater based on the Nieuport model - the SSW D.I with a 110 hp Siemens- Halske Sh.I rotary engine. This type was accepted by Idflieg in August 1916 and an order was placed for the delivery of 150 + 250 aircraft, of which, however, only 95 were realized, as the Army administration wanted the development of an aircraft with improved performance using a 160 hp Siemens- Halske engine (Sh.III).
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Transformatorenwerk Nuremberg

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  In October 1916, an order for the production of 6 Nieuport-type "D.I" biplanes was placed on a test basis by the Inspectorate of Aviation Troops (Idflieg), and the monthly output was increased somewhat. Towards the end of 1916, another order was placed, initially for the accelerated completion of 150 units with Siemens rotary engines. Parallel to this, as already mentioned, the factory premises were expanded by May 1917.
  In the meantime, the series production of the D airplanes, which had been developed in the rooms of the transformer plant during the months of January to the end of April 1917 and which amounted to 15 units per month, and which was brought to the required level of 50 airplanes per month in June, had to be aborted suddenly, since the type had been classified as obsolete in the meantime. The biplane, now in series production, met the same fate. The existing contract for the delivery of 100 aircraft and the current order were cancelled, so that only the parts already manufactured could be accepted.
  As compensation for the cancelled contracts, Idflieg offered Siemens-Schuckert Werke in Nuremberg to turn its attention to aircraft repair. The monthly output was set at 30 to 40 B- or C-type Albatros or LVG aircraft. Although an average of 25 repair orders were still received at the plant between June and July 1917, it soon became apparent that the existing workshop capacity was underutilized. In September, only 18 repair aircraft were delivered, and in October through December 1917, an average of only 5 to 6 aircraft were delivered. For this reason, Idflieg, in order to again keep the plant fully occupied, placed a new series order on Alb C.IIIs and additionally contracted the company to repair SSW aircraft built at the parent company.
  Although the Transformatorenwerk was able to absorb a large part of the workforce of the aircraft construction department as a result of the constantly changing order situation, it could not be avoided that a large part of the employees of the aircraft construction department had to be furloughed or laid off for several weeks.

Zeppelin-Werke Lindau GmbH (ZWL), (Do)

Aircraft Development:

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  Luftschiffbau Zeppelin GmbH, a part of the Zeppelin Gesellschaft, also received the request. There, it had long been recognized that the time of the great war airships was over and the company was intensively engaged in aircraft construction. The Lindau plant saw the development of the fast C-airplane as a great opportunity to establish itself in aircraft construction. One of the best and most experienced engineers of the Zeppelin Gesellschaft - Paul Jaray - was appointed to head the project.
  Coming from airship construction, where he had been responsible for the aerodynamic design of all Zeppelins, Paul Jaray was now given the task of developing such an aircraft in the shortest possible time.
  To achieve a higher speed, there were several ways:
   1. as powerful an engine as possible,
   2. the lowest possible empty mass,
   3. a good aerodynamic design and thus low drag,
   4. as small dimensions as possible.
  Paul Jaray knew the Maybach Mb VIa engines used in airship construction very well. In contrast to the BMW BMW.IIIa and Daimler D.IIIa or Oberursel UR.IIa usually used, which ranged in output from 150 to 175 hp, the Maybach Mb.IVa produced 240 hp. It was a water-cooled standing six-cylinder in-line engine with a displacement of 23.1 liters, a compression ratio of 6.08:1, an output of 240 hp (176.5 kW) at 1,800 rpm and an average consumption of 67 liters/hour. The engine was very reliable. Its only disadvantage was the high weight of 400 kg. If the Maybach was to be used, weight had to be saved elsewhere, because the empty mass of the aircraft was not to exceed one ton. This meant, however, that a metal construction or a mixed construction of metal and wood, which Jaray had in mind, was out of the question. The new airplane had to be made entirely of wood and canvas to meet the one-ton requirement. Only the engine had to be partially clad in light metal because of heat generation. By August 1917, the design was completed and submitted for review to the Idflieg (Inspectorate of Air Forces) Commanding General of the Air Forces (Kogenluft). In order not to lose any time, the Zeppelin Company decided to start building two machines immediately, without an official order from the Idflieg.
  The C.I was a two-seat biplane with normal tailplane and fixed slip-spur landing gear of wooden construction. The fuselage with an oval cross-section consisted of wooden frames and longitudinal chords and was wrapped with plywood. This construction method made the fuselage very robust and allowed for an aerodynamically favorable design. The forward fuselage accommodated the large Maybach engine, which protruded significantly above the fuselage contour. To reduce frontal drag, it was carefully clad in light metal sheeting. A sheet steel firewall separated the engine area from the rest of the fuselage. Since the radiator was centered under the upper wing, an appropriate connecting pipe had to be used between the engine and the radiator, which contained the supply and exhaust lines made of copper tubing. The engine directly drove a fixed two-bladed wooden propeller model Heine. Directly behind the fire bulkhead was the fuel tank with a volume of 220 liters.
  The two crew members were accommodated in two separate round-cut fuselage sections, one behind the other. The pilot's cockpit had no wind protection of any kind. The pilot sat low in the fuselage, able to look straight across the long fuselage structure, with the protruding voluminous engine cowling and the connecting tube from the engine to the radiator further limiting visibility. The observer sat on a turntable, so he could operate his various devices, such as camera, later FT-device, as well as in case of attack by enemy aircraft, the swiveling 7.92 mm Spandau machine gun. The ammunition supply for this was 500 rounds. Light bombs were also to be carried, with three mounts for 10 kg bombs attached to each side of the fuselage at the level of the observer's seat.
  By means of two N-struts made of aerodynamically shaped steel tube, it was firmly connected to the corresponding fuselage frames. In addition, there was a bracing to the fuselage. Two further V-posts, one on each side, also made of steel tubing, went from the fuselage at 45 degrees to the wing and were connected there to the longitudinal spars. Directly above the fuselage on the underside of the upper wing was the radiator, designed as a finned radiator. The upper and lower wings were connected on each side by a V-stem of formed steel tubing and were also cross-braced with steel cables running from the bottom of the fuselage to the V-stem connections. The tailplane resembled a rounded triangle and was also a fabric-covered wooden structure, with both spars passing through the rear of the fuselage and also forming a solid box with the spars. This connection was so strong that it could be cantilevered, which was unusual at the time.
  In September 1917, the first machine was completed in Lindau and could be tested. The aircraft generally showed good flight characteristics, only a few minor modifications were necessary, for example the aircraft was slightly top-heavy, caused by the heavy Maybach Mb IVa. This was remedied by slightly lengthening the tail of the fuselage. One complaint was the very poor visibility for the pilot, which was sought to be improved by a higher seating position. By early 1918, the second machine was also completed and had flown by mid-February. Both machines were transferred to Adlershof for the C-type competition, where they were thoroughly tested and found to be good by the frontline pilots acting as test pilots, prompting a series order from Idflieg for 200 units to Luftschiffbau Zeppelin GmbH Friedrichshafen. However, some modifications were required, as well as the substitution of various wartime bottleneck materials and equipment. The most important changes were that the ailerons, elevators and rudders were now made of fabric-covered metal structures, since the wooden frames could not withstand the stresses. The fuel tank was also moved under the pilot's seat and designed to be jettisonable for emergencies to reduce the risk of fire. The design was given the designation C.II and series production began in June 1918.
  Difficulties were encountered in supplying the Maybach engines needed for various models, including the Zeppelin-Staaken giant aircraft, as production did not keep up. By the time the armistice negotiations began on November 8, 1918, only 19 examples of the Zeppelin C.II had been completed.
  By order of the Allied Control Commission, these were to be scrapped. In a night and fog operation, however, the Swiss Air Force acquired all 19 machines, where they were then successfully used as reconnaissance aircraft until 1928.
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Zeppelin-Werke Lindau GmbH (ZWL), (Do)

  Dipl. Ing. Claude Dornier, born in Kempten on May 14, 1884, joined the Zeppelin Luftschiffbau as early as 1910 and carried out preliminary work for a large steel airship. After the outbreak of war in 1914, Count Zeppelin decided to take up aircraft construction as well, founded a new shipyard in Seemoos and commissioned C. Dornier to develop giant flying boats here. In 1916, factory buildings were added in Reutin near Lindau and Zech on the Bavarian-Austrian border. In 1917, these facilities were transformed into the independent company "Zeppelinwerke Lindau GmbH" (ZWL) and continued to be run by Dornier as managing director. A number of giant flying boats were built in Seemoos, the first of their kind, designed in all-metal construction by Dr. C. Dornier, which today are generally attributed to the Dornier plant, although they were built by the Luftschiffbau Group and Claude Dornier did not build aircraft on his own account in Friedrichshafen until after the First World War.
  Around the time Flugzeugbau-Friedrichshafen GmbH was founded as a new subsidiary of Luftschiffbau for the construction of seaplanes, the decision matured at Zeppelin to find another company - Zeppelin-Werke, Lindau, GmbH.
  The seaplanes developed by Claude Dornier at the Seemoos and Reutin factories bore the military abbreviation "Do".


Aircraft Development:

  The influence of the Lindau developments on wartime events can be considered extremely small. Apart from a few frontline missions of the Rs.III, no Dornier aircraft took part in any significant combat missions. However, the technological advancement of metal aircraft construction by Claude Dornier and his engineers is even more noteworthy. The achievements of the early flying boats had a significant influence on the design of seaplanes of the postwar period and beyond.
  Zeppelinwerke Lindau GmbH was one of the oldest companies on the continent, which for many years considered metal aircraft construction to be its sole task, avoiding the tubular constructions and welding of any kind that were otherwise generally used.
  Large funds provided by the late Count Zeppelin to the head of the company, his long-time employee in airship construction, Mr. Dornier, enabled the company to work on the methodical development of the metal aircraft for over six years as a purely experimental company.
  The experience gained during this time was extremely valuable and became fundamental for metal airplane construction.
  From the very beginning, only high-quality steel and duralumin were used as construction materials. While highly stressed parts, such as spars, engine mounts, spars and the like, were preferably made of hardened steel, duralumin was mainly used for hulls, boats, floats, and spars. The development of, particularly favorable cross-sectional shapes of profiles made of steel and light metal was one of the company's main tasks for many years.
  Extensive load tests with spars, struts, complete wings, and airplanes created the necessary documentation for calculating the aircraft. Hand in hand with this work went the testing of the aircraft in the air.
  The company's field of activity was seaplanes and landplanes of all types and dimensions. From the very beginning, special attention was paid to the construction of monoplanes and aircraft without bracing.
  The factory built and designed airplanes from 160 to 2400 HP and, thanks to its unique experience, was able to meet even the most demanding requirements. The company was particularly involved in the construction of flying boats.
  While the first Dornier flying boat Rs.l, built in 1914/15, still had the usual support floats, the second type Do Rs.II was already an inherently stable hull.
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Zeppelin Companies
  
  Ferdinand Graf Zeppelin was born on July 8, 1838 in Constance on Lake Constance and died on March 8, 1917 in Berlin-Charlottenburg. After completing his school education, he began his officer career in the Imperial Army. In 1863, by now in the rank of lieutenant, von Zeppelin was given leave of absence from the army to participate as a military observer in the American War of Secession joining the forces of the Northern States. In his capacity as observer, the Count took part in a reconnaissance flight in a balloon on August 19, 1863. Possibly because of this experience, he subsequently pursued the idea of building aircraft.
  After Graf von Zeppelin's discharge from military service, he became intensively involved with the question of building guided balloons, later referred to as airships. In 1894, Zeppelin presented a concept for a rigid airship to a council of experts, but it found no supporters. Undeterred, the count continued to work on his vision and one year later filed a patent for his idea of an airship.
  In 1898, Zeppelin succeeded in founding the "Gesellschaft zur Forderung der Luftschiffahrt" (Society for the Promotion of Aerostation). More than half of the capital stock of 800,000 marks came from the count's private assets.
  Construction of the first airship, LZ 1, began in 1899, and the first ascent took place a year later, on July 2,1900. The airships LZ 2 and LZ 3 followed in 1906. The fire catastrophe of the LZ 4 in Echterdingen on June 20, 1908, did not mark the beginning of the ruin of the Zeppelin Society, but, thanks to the support of the German people in 1909, the upswing of airship construction in Germany.
  From the proceeds of the national Zeppelin donation, a total of over 6 million marks were collected, Count von Zeppelin founded the "Luftschiffbau-Zeppelin-GmbH" (LZ) with a capital of one million marks. With the remaining donation money, Zeppelin established the "Zeppelin Foundation", which still exists today and is based in Friedrichshafen. The LZ was owned by the Zeppelin Foundation.
  The parent company of all subsequent Zeppelin companies was "Luftschiffbau Zeppelin GmbH", which had initially been founded by Count Zeppelin exclusively for the construction of rigid airships. The company's factory, where the first Zeppelin airship, LZ 1, was built in 1900, was located in Manzell on the northern shore of Lake Constance, seven kilometers west of Friedrichshafen.
  In 1910, Graf Zeppelin succeeded in founding the Delag Luftschiffahrt Gesellschaft (Deutsche Luftschiffahrt A. G.).
  Right at the beginning of the war (August 1914) he gave simultaneously:
   a) to his engineer Claude Dornier from Friedrichshafen the order to build huge metal seaplanes and
   b) to Professor Baumann from Stuttgart the order to build huge land planes.
  New companies were founded for these purposes:
   (a) Zeppelin-Werke GmbH, Lindau, which bought the then Reutin automobile workshops as a factory.
   (b) For the construction of the giant airplanes, the "Versuchsbau Gotha Ost GmbH" was initially founded with capital from Zeppelin and Bosch, whose workshops were housed in the premises of the Gothaer Waggonfabrik in Gotha. It was there that Professor Baumann built his first "R" aircraft, the "VGO".
   (c) Around this time, a new subsidiary of Luftschiffbau, Flugzeugbau-Friedrichshafen GmbH, was founded for the construction of seaplanes. Zeppelin Luftschiffbau (LZ) left its workshops in Manzell to it as a factory. The Flugzeugmeisterei gave it the abbreviated designation "Fdh".
   (d) Since it had to reckon with air raids due to its proximity to the border, it set up new workshops in its airship harbor in Staaken in 1916 near the two large airship hangars that the German government had just built. After the premises in Gotha were no longer sufficient, the operating facilities were also relocated to Staaken, which
   (e) led to the founding of the "Flugzeug-Werft Staaken GmbH".
  In 1917, Flugzeugbau-Friedrichshafen GmbH established an assembly and testing station for seaplanes in Warnemunde, which was named "Flugzeugbau-Friedrichshafen Werft Warnemunde".
  From 1915, Luftschiffbau GmbH used hangars and workshops in Wildpark near Potsdam, a former military hangar in Lowenthal near Friedrichshafen (until 1916), in addition to its factory in Friedrichshafen to increase its production capacity.
  When the demand for airships dwindled, Flugzeug-Werft, Staaken GmbH decided to take over the work carried out in Gotha by Versuchsbau Gotha-Ost GmbH. It adopted a new name: Zeppelin-Werke Staaken GmbH (for the construction of airships and giant aircraft in Staaken).
  In summary, the situation of the Zeppelin companies at the end of World War I was as follows:
   (a) Zeppelin Luftschiffbau GmbH ("LZ"), for the construction of rigid airships. Plants in: Friedrichshafen and Lowenthal.
   (b) Zeppelin-Werke Staaken GmbH ("Staak"), for the construction of rigid airships and giant aircraft. Factory in Staaken.
   (c) Zeppelin-Werke Lindau GmbH ("Do"), for the construction of giant metal seaplanes. Plants in: Reutin and Seemoos.
   (d) Flugzeugbau-Friedrichshafen GmbH (Fdh), for the construction of seaplanes. Plants in: Manzell and Warnemunde.
   (e) Deutsche Luftschiffahrt AG ("Delag")" for the operation of civil air transport companies.
   (f) Zeppelin Gebaude Gesellschaft mbH, for the construction of airship hangars. Headquarters in Berlin, Kurfurstendamm, 13.
   (g) Ballonhullen-Gesellschaft mbH, for the manufacture of balloons, in Berlin-Tempelhof.
   (h) Maybach Motorenbau AG, for the construction of engines for airships and aircraft. Factory in Friedrichshafen.


Zeppelin-Werke GmbH, Staaken near Spandau (Berlin) (Staak)

  In 1913, Hellmuth Hirth, a well-known German aviator, and Gustav Klein, a Bosch director, planned a giant airplane with which they would cross the Atlantic Ocean to America two years later. Count Zeppelin became aware of this. He was very interested, since he was pursuing the same goal, albeit by other means. Count Zeppelin saw no competition in the project, which led to the foundation of the "Versuchsbau GmbH Gotha-Ost" (VGO) in 1914 with Zeppelin's support and participation.
  The workshops provided by the Gothaer Waggonfabrik were soon no longer sufficient to achieve the goals set. This led to R-aircraft construction being transferred to Staaken near Spandau/Berlin, where a shipyard belonging to Luftschiffbau Zeppelin GmbH had already been set up in 1915. From 1915 onward, Luftschiffbau GmbH used hangars and workshops in Wildpark near Potsdam and a former military hangar in Lowenthal near Friedrichshafen (until 1916) to increase its production capacity, in addition to its factory in Friedrichshafen.
  Since the sites on Lake Constance had to expect air raids due to their proximity to the border, Luftschiffbau GmbH set up new workshops in its Staaken airship port in 1916 near the two large airship hangars that the German government had just built. The Flugzeugmeisterei gave it the short name "Staak."
  On January 25, 1918, the Staaken-based plants Luftschiffbau Zeppelin GmbH (Plant I) and Flugzeugwerft Staaken GmbH (Plant II) were merged.The founders of this new company were the same shareholders who had owned the predecessor companies, namely Generaldirektion Luftschiffbau Zeppelin, Friedrichshafen am Bodensee.
  Nevertheless, the parent company of the Zeppelin companies was "Zeppelin Luftschiffbau-GmbH", which had been founded by Count Zeppelin for the construction of rigid airships. The company's factory was located in Manzell on the northern shore of Lake Constance, seven kilometers west of Friedrichshafen.


Aircraft Development:

  Right at the beginning of the war (August 1914), Count Zeppelin commissioned his engineer Dornier from Friedrichshafen to build huge metal seaplanes. Professor Baumann from Stuttgart, on the other hand, was commissioned to build giant land planes.
  To build the giant aircraft, the Versuchsbau Gotha Ost GmbH (VGO) was initially founded with capital from Zeppelin and Bosch, and its workshops were housed in the premises of the Gothaer Waggonfabrik in Gotha. It was there that Professor Baumann built his first "R" aircraft.
  The VGO project was a three-engine biplane with one pulling and two pushing propellers. One engine was located in the fuselage nose section and two in carefully profiled nacelles, "suspended" between planes on the biplane box legs. Such a layout allowed to dispense with a relatively short landing gear struts when using large-diameter propellers. Machine gun turrets were installed at the front end of the engine nacelles, with gunners serving simultaneously as engine mechanics, operating in flight the wing motors. The aircraft was powered by six-cylinder single-row liquid-cooled Maybach engines, similar to those used on Zeppelin airships. For their time they were quite powerful engines, producing up to 245 hp in takeoff mode. However, the reliability of their operation, as they say, left much to be desired, so the crew had to include three engine crew members. The total number of the crew reached 8 people. The construction of the first prototype designated by the index VGO.I was completed surprisingly quickly. Already in April 1915 it took off.
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