Category Danish civilian aviation

Nielsen & Winther

Nielsen & Winther A/S was founded in 1867 as a blacksmith and machine toolshop, specializing in lathes. They later expanded their product portfolio to include machines for the weapons industry as well as aeroplanes. The drawing of the factory from 1917 is very optimistic, but in reality the company was in a crisis, and was bought by Vølund A/S in 1920. Some of the buildings still exists to this day.

 

 

The company produced the Type Aa fighter aircraft, as well as a couple of prototypes. Six were sold to the Danish Army,  but three later crashed, and the remaining planes were then banned from flying.

Rumour has it that the pilots had long been worried about the safety of the construction, but the ban was apparently due to the poor reliability of the Thulin engine used.

 

Although this plane was the first indigenous aircraft in the Danish army, it has come to light that at least some of the drawings were from the Thulin factory in Sweden. In fact, some of the plans I have seen, were marked named the Thulin ‘L’  aircraft.

 

 

Another aircraft type was apparently sold to South America.

 

 

Any photos of the N&W planes, with the exception of the N&W Jager, are most welcome.

Danish Balloons before the Great War

A small hot-air balloon was seen over the roof-tops of Copenhagen on the 27th of December 1783. It was only one year after the brothers Montgolfier had sent up their first balloon in France.

The first Danish balloon flight taking a human being aloft took place on the 1st of October 1806 when  Professor Robertsen from Moscow ascended in his balloon from Rosenborg castle.

The first Dane to fly in a balloon was Studiosus Johan Peter Colding, who on the 23rd of April 1811 asceded in his home-made 40 ft (diameter) balloon. The trip from Blegdam 2, to Brønshøj Bakke took an hour. Colding was well know for his experiments in aeronautics, and he later succeded in sending mail by air across Øresund to Sweden.

The next balloon captain to try his luck was the Italian Joseph Tardini who had been hired by Tivoli.  The balloon crashed into the sea and Mr. Tardini drowned. His passengers, a woman and a child made it to shore.

Tardini’s balloon was later sold for 1085 Rigsdaler, and it was in this balloon that the Swede Granberg was immortalized. Granberg attempted to go aloft in the balloon, on Sunday the 26th of July 1857 from the square in front of the Danish parliament, Christiansborg. The balloon got caught on the roof of the Hofteatret building. To this day, the phrase “Den gik ikke Granberg” (That didn’t work, Granberg), is used in Denmark – Our ridicule of everything Swedish is obviously not new.

Tivoli continued to sponsor balloon flights, and many successful flights took place with paying passengers. The air captain, Lauritz Johansen, had a recordbreaking 117 ballon trips under his belt when he retired.

Jacob Christian Annasti Nees

Mr. Jacob Christian Annasti Nees publishes a book in 1860 called “Om Luftsejlads baseret paa Fugleflugt” (loosely translated as “Flying based on the study of Birds”). In the publication, Mr. Nees explains the “mechanics of flight”. He mentions the forces on a bird in flight, including lift, thrust and drag. He explains the propulsion of a birds wing when it flaps up and down, as well as as prepares and solves equations for the forces acting on the wing.

He argues that a flying machine with moving wings (ornithopter) must be the correct solution to heavier-than-air flight. His machine has a steam-engine in the center of the body. The wings are to move up and down for propulsion, and the tail is for directional control. Nees also discusses the difficulty of take-off, and imagines his airship be placed on a railway car and accelerated until take-off speed.

He estimated that an airship with a wingspan of about 36 feet would be able to carry 9 persons (130 pounds each) and with a 20 “Horses Power” engine. He had though out a steam-engine that would weigh around 25 pounds per horse power, and would cost 32 skilling per HP-hr. The daily wages for a worker was about 25 skilling per day. (1 rigsdaler = 6 mark, 1 = mark 16 skilling , 1 rigsdaler = 96 skilling). The price of an aircraft in 1860’s prices was estimated to 30,000 rigsdaler.

He assumed that regular flights between Copenhagen and Paris would take place with 5 flights a day, and started calculating operating costs and profits. Talking about selling the skin before the bear was shot!

Mr. Nees apparently worked in Sweden from 1849 to 1850, according to this website: carlotta.gotlib.goteborg.se/pls/carlotta/VisaPerson?pin_perMasidn=222160

visat namn: Nees, Jacob Christian Annasti
efternamn: Nees
förnamn: Jacob Christian Annasti
tidspunkt – födelse: 1812-03-07
tidspunkt – död: 1901-10-17
yrke: fotograf
land: sverige
adress: Dahlanders hus [1849-1850]

Mr. Nees apparently tried to find investors for his project, but failed.

J.C.A. Nees was born March 7rd, 1812 in Hjørring. Was educated as “Polyteknik Kandidat” (Engineer). Worked at Mønten (Royal Mint). Was working as Daguerrotypist (Photographer) and as a telegraphist. Died Oct. 10, 1901

Ornithopter
The ornithopter is a machine with flapping wings that  is designed to fly like a bird. The German brothers Gustav and Otto Lilienthal came to the result that a man with two pairs of wings is able to “lose” half his body weight. In other words, humans are too heavy and deliver too few “horse” power to the wings to sustain powered flight – It was necessary to find another means of lift. I have included this page here, as I find the aparatus used for testing so ingenius.

Klampenborg & Danmark

Ritmester Clausen-Kaas had just completed Klampenborg in 1908 and wanted to promote this new horse-race race-track as the ‘happening’ place. He bought a Percal balloon named “Danmark’ and a Voisin Aircraft – both from France. He built a hangar for the aircraft and had a gas-pipe installed from the near-by gas storage facility. He then made an agreement with the newly opened Dansk Aeronautisk Selskab (Danish Aeronautical Society).

This small balloon broke a record on its maiden voyage, by flying for 8 hours and 20 minutes and landed near Posen in Prussia (Now Poznan, Poland), some 430 km away. Danmark’s second voyage took it all the way to the Russian border, 545 km away.  The third balloon voyage was from Aarhus to Upsala, Sweden. The balloon sport gained incredible popularity.

Danmark was involved in many eventful voyages, mainly to Sweden, Norway and Germany, and took part in several ballooning competitions – mostly in Germany.

On the night of 18th of May 1910, earth passed through the trail of Halley’s Comet. Denmark was sent up. Its gondola was filled with scientific equipment and vacuum flasks. It was the Meteorological Institute trying to collect traces of space-dust in earth’s atmosphere.

A new balloon christened “Danmark II” was procured in 1910 when Danmark finally gave in. The photo shows Danmark, during the Skandinavisk Ballonkonkurence (Scandinavian Balloon Contest). A competition that Norway won!

Danmark II flew regularly during the following years, from Tivoli Gardens. It it worth noting that the longest voyage was 740 km, and the fastest was 75.6 km/hr (47 m.p.h).

Skandinavisk Aerodrom A/S

Scandinavia’s first proper Aerodrome was Kløvermarken to the south-east of Copenhagen. This triangular plot of land was rented by Skandinavisk Aerodrom A/S, a company established with the sole purpose of arranging airshows similar to those in Paris. The company raised a tall canvas-covered fence all around the aerodrome, giving an idea of the altitudes achieved during that period.

On this grass-field, flyers practiced and prepared for what had to be the ultimate feat, crossing the small straits to Sweden.

The flyers built their own aircraft, based on french designes. The kids in the neighbourhood soon gave these strange creations nicknames.

FlyerAircraftModel
Nervø, AlfredWampa?
Svendsen, RobertBadeanstalten (The Public Bath)Voisin 1910
Severinsen, SørenKolonihavelysthuset (The Allotment House)Own Construction
Nielsen, PeterOwn Construction
Ellehammer, J.C.H.Græsslåmaskinen (The Lawnmover)Ellehammer Standard
Folmer HansenSandgraveren (The Sand Digger)Farman-Voisin 1909

 

It’s quite obvious from the nicknames, that most of these aircraft spent more time on (or in) the ground than in the air.

Visitors from abroad also used the Kløvermarken Aerodrome, including famous flyers like Pergoud, Chanteloup, and Chevillard.

Early Scale Modelling

The first scale model event in Denmark was on the 1st of January 1910. Students at “Det Danske Selskabs Skole” (Danish Society’s School) had been making models since the 20th of December, the year before – a total of 10 days. There were models of all the known aircraft of the time, incuding Wright, Bleriot, Latham, Antoinette and Santos Dumont. And the models DID fly. The first prize was won by Bent Rom, one of the volunteers at the Kløvermarken Aerodrome.

Jacob Christian Hansen Ellehammer

Jacob Christian Hansen Ellehammer was educated as a watch-maker, but soon got interested in various mechanical and electrical disciplines. He was a great inventor, and many of his inventions were literally way ahead of his time.

He made his money on a revolutionary water pump, and the got interested in light combustion engines. He soon married the combustion engine to a bicycle frame, and his “Elleham” motorcycle became a huge success.

Around 1903-1904, he started the development of a light aircraft engine. The idea of more than one cylinder was not new, but to save weight, he came up with the idea of mounting all the cylinders in a circle around a common crank case, thereby reducing the weight substantially. This, the worlds first radial engine, had 3 cylinders and produced 9 horse power. By 1906, he had managed to increase the power output by a factor of 2.5, and his model 1906, 3-cylinder engine produced slightly over 20 horse power.

Ellehammer and his brother had played with kites as children, and he knew they could produced enough lift to carry himself, on a windy day. So, he based his first aircraft on a triangular kite design. This was his second stroke of genius. By basing the design on a kite, the weight of the aircraft was drastically reduced, as he did not need heavy wooden wing spars and wing ribs, but could make do with a few metal tubes. The first Ellehammer aircraft were probably what we, today, would call hang-gliders, rather than fixed-wing aircraft. During his experiments, he added a second wing, tied to the first one with ropes. The top wing did not have any metal frames, and was, in fact, acting much like a ships sail. This was his 3rd stroke of genius. In effect, he got twice the lift, but added only 3.5 kg (7 lbs) of weight.

He then turned his attention to stability and control. Again, he came up with a brilliant idea. Longitudinal stability was controlled automatically by a pendulum that always pointed downwards, linked to the elevators. When the nose of the aircraft dipped, the pendulum would swing forward, pulling on the elevators, until the aircraft’s nose went up again. The opposite would obviously happen when the nose went up. Lateral stability was done by shifting the weight from side to side, bending the wings.

So, by 1906, he had all the elements required for powered, controlled, flight; 1) a light but powerful engine, 2) an extremely light aircraft and 3) a system of control.

For his first experiments, he controlled the aircraft from the ground using wires, very much like controlling a kite. When he had all the kinks ironed out, he started the first man-made flights. He performed these with one wing-tip tethered to a pole, making it go around in circles. For this purpose, he had constructed a hangar and a circular cement runway on the island of Lindholm, in the South-East of Denmark. This was another innovation, as this was the world’s first runway.

On the 12th of September 1906, Ellehammer took off in his second aircraft constructed, the Ellehammer II. He flew 42 m (140 ft) at a hight of 50 cm (20 inch). This flight took place a few days before the famous flight by Santos Dumont in Paris.

The next aircraft made by Ellehammer, the Ellehammer III, was able to take off and land on grass. He made more than 200 free andcontrolled flights in this aircraft, without even a single mishap or crash.

It is very interesting to note that Ellehammer had no knowledge of what the Wright Brothers had achieved in the USA, and that he came to the same conclusions as the Wright Brothers, roughly at the same time in history. Also, both the Wright Brothers and Ellehammer shared roughly the same backgrounds, in the bicycle/motorcycle business.

The Ellehammer IV, was the first Ellehammer aircraft with fixed wings, spars, ribs and a “proper” curved wing profile. On the 14th of January 1908, he entered the record books as the first person in Germany to fly, winning an astounding 5000 Mark for his feat. He few 190 meter in 3 meter’s height. The flight took 11 seconds!

The next aircraft, the Ellehammer V, was a flying boat.

By 1909, he built his “Standard Monoplan”. This aircraft was used by Count Moltke, who tried to cross the Øresund, the straits between Denmark and Sweden. The Count did NOT win the prize. The Standard Monoplan still exists to this day. A replica of it was made by Kramme & Zeuthen, and used by Viggo Sylvest Jensens Flying Circus.

By 1909 Ellehammer had obviously heard of the developments in France, and he lost interest in aircraft. Instead, he turned his attention to the helicopter, and by 1912 he succeeded in taking off in a helicopter of own design. The machine featured a counter-rotating propeller.

 

Berg & Storm I, II and III

Engineer Olaf Berg became manager of Burmeister & Wain’s Paris office in 1908. The office was in charge of marketing and sales of B&W’s centrifuges for homogenizing and pasteurizing milk. A technology invented 50 years earlier. Sales was not going well.

During his stay in Paris, Berg had the opportunity to visit the aerodrome at Issy-les-Moulineaux, where he witnessed the flights of  Henry Farman, Louis Bleriot and Leon Levasseur.

What made Berg think about aeroplane production in Denmark was the slow sales of centrifuges, and the impressive results of the Wright brothers, which he saw, during their visit to France during 1908.

Wilbur’s flights created quite a stir in the aeronautics community, because of the ease of banking their arcraft. Instead of making large turns, the Wright flyer could turn on a dime. Wilbur’s flights in Hunaudieres in August 1908, introduced the “Gauchissement” (Wing warping) control system to the French flyers.

During a short visit back in Denmark, Berg discussed what he had seen with engineer Louis Storm, and they both agreed to start an aircraft production. The main purpose was to demonstrate that aeroplane production was feasible in Denmark, and first and foremost to build a workable aeroplane.

B&W’s director Dessau was not entirely convinced, but he allowed the two gentlemen to use the facilities at B&W for their aeroplane venture. The news leaked, and the press soon brought articles about the aeroplane.

Berg & Storm I

Berg & Storm chose the Bleriot XI as a model for their aeroplane, but used the landing gear of the Antoinette monoplane constructed by Leon Levasseur. Bleriot had just crossed the english channel in a Bleriot XI, and Hubert Latham had performed incredible stunts at the airshow at Blackpool.

The fuselage was constructed during October 1909 from Oregon-Pine, Ash and plywood. The model-makers at B&W did the carpentry.

The wings, as well as elevators and rudders were covered with balloon-fabric (silk covered in rubber). The silk was attached to the wing by clamping it to the wings using wooden stringers on the outside of the wing. The wings were using standard ailerons.

The metal work was constructed by the centrifuge department at B&W.

The engine was a 3-cylinder Anzani, identical to the engine used by Bleriot during his channel crossing. It was able to deliver 30 BHP at 1600 r.p.m. The speed of the engine was very difficult to control. It was either full speed or nothing.

The machine was rigged by Niels Petersen, the machine-shop foreman. He had a keen interest in motor-cars, and his experience with fast engines, made him ideal for the Berg & Storm project.

The aircraft was ready by February 1910, and it was transported to Kløvermarken aerodrome, outside of Copenhagen. The first flight was performed by Knud Thorup, a vine-merchant from Aarhus that had taken flying lessons in France the year before.

The controls were arranged as follows: Rudder by foot pedals, elevator by pulling the joystick backwards and forwards, and wing-warping by twisting a wheel mounted vertically on the stick. This control methods, “DEP-control”, named after its inventor Deperdusin is still in use today.

The initial use of ailerons, as was popular with French aviators, proved hard to control on the Berg & Storm I, and the wing hit the ground during the first take-off attempts. The “Gauchissement” system was quickly adopted.

The Berg & Storm I flew for the firs time on the 4. Juli 1910 at 20:30. The wing incidence was 6 degrees, but it should probably have been 12, resulting in the aircraft flying nose-down, with the propeller having 6 degrees of down-thrust. Engineer Berg was extremely excited, and a young lady handed Thorup a rose as a toke of her appreciation. Flights followed almost daily, including many with a new engine designed by Niels Petersen, until Septembed 1910, where the plane crashed with the unexperienced Berg at the controls.

Specification B&S I

Wingspan: 8 m
Wing area: 15 sq. m
Length: –
Speed: 70 km/h
Weight: 190 kg
Engine: Anzani 30 hp.
Petrol Tank: 30 l
Propeller efficiency: 0.65.

Berg & Storm II

The Berg & Storm II aeroplane was a new construction. The fuselage was triangular in cross-section, something copied from the Antoinette aeroplane. The wing-profile was identical to that used on the Berg & Storm I. The fuselage was much slimmer than the B&S I fuselage, and constructed entirely out of wood and covered in plywood.

The triangular shape made control difficult. All controls were arranged on the stearing column, with the exception of the control for the engine oil, that was controlled by a foot-pedal.

The Berg & Storm II was constructed at a new hangar at Kløvermarken, bought by Berg & Storm during 1910. The hangar had the letters “B&S” written in large black lettering over the hangar doors.

Storm got a job in Norway during 1911 and it was Berg and Niels Petersen that finished the B&S II. The new machine was ready by April 1911.

The first flight was by Niels Petersen, that “just” had to learn how to fly first. He got his certificate on the B&S II, after about two months of training. The aeroplane proved a good flyer and Niels Petersen made several figure-8 flights and several landings.

Berg was now confident that they had a solid product, and he planned a large tour during 1911 – the so called “Danmarksflyvning” (Denmark-Flight). The trip would start at Skagen, and they would then perform all the way down throught Jylland, across Fyn ending back in Copenhagen.

Many records were broken on this trip, including height-records (500 meter) and duration (27 minutes), both from Sohngaardsholm Castle  in Aalborg. The 27 minute record flight would also be the last Berg & Storm II flight, as Peter Nielsen ran out of fuel and had to crash-land outside the airstrip at Sohngaardsholm parklands.

B&S II Specification

Wing span: 9,5 m
Wing area: 17 sq. m
Length: –
Weight: 270 kg
Engine: Niels Petersen 3-cylinder 50 HP

Berg & Storm III

A new aircraft, the Berg & Storm III was soon ready. It was similar to the Berg & Storm II, but it was designed as a trainer, and had two seats in tandem. The new aeroplane had the same wing-span as the Berg & Storm II, but it had a different airfoil – the “Eiffel 14”. The wing area had been reduced to 14.5 sq. m. resulting in a much faster landing speed, and a more difficult take-off.

The student was supposed to sit behind the pilot and watch his movements during flight, but the engine was still a Peter Nielsen 50 HP engine, and take-off proved difficult when a passenger was onboard.

The Berg & Storm III took flight during December 1911. The aeroplane was immediately sold to General Grut, who established a flying school for army personel from December 1911, with Peter Nielsen as instructor, until 1912, where General Grut donated the aeroplane to the Army.

This was to be the beginning of the Army Flying School, which was located on Kløvermarken, just outside Copenhagen. The Berg & Storm III was decomissioned two years later, in 1914. The aircraft today resided in Danmarks Flymuseum in Stauning, Danmark.
Berg & Storm III Specifications

Construction: Wood and Canvas
Engine: 3-cylinder, Nielsen
Controls: wing-warping
Wing-span: 8.8 m
Length: 8.34m
Height: 2.10 m
Weigth: –
Speed: 95 km/h
Range: –
Duration: 27 mins

Viking Aeroplan & Motor Co.

Viking Aeroplan & Motor Co. was established during WWI by Erik Hildesheim. Its location was Toldbodgade 2, Copenhagen. It quoted the Royal Danish Army for several aircraft, based on a French design, but none were built. The company did not own any toolshop and the airplanes were to be built at “Københavns Værft og Flydedok” (Copenhagen Shipyard). They did however manage to design a 220HP, 6 cylinder engine that was built by “Maskinfabrikken Atlas”. It was sent to the Naval Shipyard that constructed the OV-series of flying boats for testing, but the company had folded before the engine tests were completed.

Director, Erik Hildesheim, later joined the German company “Rohrbach Metal Aeroplan A/S” – a German company that circumvented the Versailles treaty by building airplanes outside of Germany.

Dansk Luftexpres

Herr Sablatnig, the well-known German aircraft constructor, and the owner of Sablatnig Flugzeugbau GmbH, visited Kløvermarken in 1919. He brought several small machines with him. These machines were originally build for night bombing, and had been re-fitted as passenger aircraft, after the Treaty of Versailles had banned all military aircraft production in Germany.

One of these aircraft, the Sablatnig P.I was especially impressive, as it could carry four passengers in an enclosed cabin. This was the first closed-cabin aircraft to visit Denmark. The machine was small, cramped, uncomfortable, and basically consisted of a “lid” over some upholstered pillows. The pilot was sitting in an open cockpit behind the passenger cabin. Access to the cabin was through the “lid”. However, it was nevertheless a closed-cabin machine.

Dansk Luftekspress was incorporated in 1919 based on these Sablatnig PI machines. The company started carrying passengers around the Danish provinces with two Germans as pilots. The company was not very active, and was eventually dissolved.

WANTED – Photos of the Danish Sablatnig P.I.


Dansk Luft Rederi

Starting the company

Denmark was visited by many German pilots and aircraft constructors immediately after 1918, including Hermann Goring and Anthony Fokker, as well as a couple of English and French aviators.

A Mr. Henrik Tholstrup, bought several containers of old German planes and spares, which arrived during the summer of 1919. The company started in September 1919, with three L.V.G.s, two Fokker D.VII, and later also two Rumpler C.Is.

Dansk Luft Rederi was a pioneer in Danish aviation and their constant promotion of aviation had a great impact on flying in Denmark.

Marketing

A borrowed French Goliath aircraft was used to take paying passengers up, and the company’s German mechanic performed wing-walking as well as hanging in a rope-ladder suspended from a L.V.G.’s landing gear. Aerobatics were performed with a Fokker D.VII. Surely a magnificent sight.

Dansk Luft Rederi flew from Lundtofte aerodrom, which was owned by the Danish Army. Danish Army pilots were then trained on the L.V.G. machines before being sent to France to take the pilot’s certificates. The training of the Army pilots by Dansk Luft Rederi was part of the payment for borrowing the Lundtofte Aerodrom.

A movie called “Gudebilledet” was made with the Swedish Heart-Throb Gösta Ekman (Senior) in the leading role. An aerial dog-fight between the company’s L.V.G. and their Fokker D.VII was filmed.

The company also flew on new year’s eve 1919-1920 with a giant banner painted with the word “Politiken” attached to the lower wings  (Politiken is a Danish newspaper).

Flying

The actual passenger flying started in ernest in spring 1920, between their base in Lundtofte, and many provincial towns. The route between Lundtofte and the North-Sealand beaches were a favourite route.

Lundtofte Flyveplads

A hangar fire on 18th of June 1949 triggered the closure of the Lundtofte Aerodrome. Danmarks Tekniske Universitet was built on the site. Here is a map from Google Earth. No prize for guessing where the runway was. If you click on the photo to enlarge it, you can see a red box showing the location of the administration and training building and the two hangars. The blue line is the highway, the blue box the entrance and the green box the airfield.


Nordisk Luft Trafik

The “Nordisk Luft Trafik” company was started by Mr. Bendt Rom on the 6th of December 1919 and was situated at the aerodrome in Glostrup. The company’s only machine was the D.F.W. brought to Denmark by Hauptmann Hermann Göring during his visit to the Scandinavian Airoplane Exhibition (Skandinavisk Flyveudstilling) in 1919.

The company started arranging passenger transport around the country, but only managed to get a single flight. The poor result was contributed to the pilot who disappeared for 14 days on his way to Rødby. The machine was parked in Rødby until it fell apart.

WANTED – Photos of anything Nordisk Luft Trafik.


Dansk Luft-Transport

Dansk Luft Transport was founded in 1925 as a direct competitor to the state-owned Det Danske Luftfartsselskab. It was sponsored by the German aircraft manufacturer Junkers, who tried to standardize on a single aircraft for the entire Europe. The company had two Junkers F13 aircrafts and flew daily on the route Copenhagen-Berlin-Dresden.

Through a state-concession, Dansk Luft-Transport was furthermore obliged to service the competitors machines at the DDL run airport. It was not surprising that Dansk Luft-Transport was constantly struggling to get the necessary flying documents and certificates, and the company folded in late 1926.

The picture here shows the Junkers F-13 machine T-DBOT behind the actors Henrik Bentzon and Betty Nansen.

A Junkers F-13 was used in the silent movie “Vester-Vov-Vov” by Fyrtaanet & Bivognen  (Pat & Patachon / Long & Short / Telefonstolpen og Tilhengeren).

Junkers F-13

Rohrbach Metal Aeroplan Co. A/S

Adolf Rohrbach was born in 1889 and got a job at the Blohm & Voss shipyard right after he graduated as engineer. He then moved to Luftshiffbau Zeppelin in Friederichshafen, near Lake Bodensee. As an aside, Claude Dornier, also worked at Zeppelin at the time. A few years later Rohrbach was transferred to the Zeppelin works in Staaken near Berlin where he worked on the giant Zeppelin bombers. Rohrbach soon became the main design engineer.

After WWI, the company started the design of a civilian airliner called the Zeppelin-Staaken E4/20. The airliner was of revolutionary design. It was the first metal stressed-skin design in the world. It had a capacity of 12-18 passengers in an enclosed cabin. It even had an on-board toilet. The airplane first flew during November 1920 with an average speed of 225 km/h. Because of the advanced construction principles, the Allied Control Commission responsible for monitoring Germany’s compliance with the Versailles treaty had the aircraft destroyed, and the Zeppelin company at Staaken closed down during 1921.

The stressed-skin design was so advanced, that foreign aircraft manufacturers were lining up to study the design methods (It is worth nothing that it remains the preferred method of aircraft construction to this day!). The huge level of interest prompted Adolf Rohrbach to set up the Rohrbach Metall-Flugzeugbau G.m.b.H. in Berlin in 1922.

The Japanese were then building up its design capabilities, and the first order came from Mitsubishi, for two flyingboats using the Rohrbach metal construction techniques.

To circumvent the limitations imposed on Germany by the Versailles treaty, Rohrbach set up the Rohrback Metal Aeroplan Co., A/S subsiduary company in Denmark, in 1922, to manufacture the aircraft. The aircraft was designed in the Rohrbach main office in Berlin.

The company’s Danish offices were located at Øresundsvej 142 in Copenhagen, just 100 meters from the sea. The Rohrbach company tore down their unused factory in Germany and re-built in in Denmark using German labour. The company also constructed a hangar at Kastrup Lufthavn (Kastrup Airport), a few miles south of Copenhagen.

Rohrbach primarily designed large flyingboats, and the first, the Rohrbach Ro-II, was test-flown near Kastrup Airport in Copenhagen during the month of  November 1923. The fuselage was constructed using sheet-metal formers and a duraluminium skin. The sheet-metal formers separated the flying boat’s hull into several waterproof compartments, making the Ro-II “unsinkable”. The two 360 bhp Rolls-Royce Eagle IX engines were situated on struts above the wings, with an adjustable rudder that could be rotated, to trim out the aircraft, should an engine drop out. The main wing was constructed using a huge box-spar, with the leading and trailing edges riveted to the wing box. Additional safety features included dual controls and the inclusion of two telescopic masts with schooner-like sails.

The narrow wings resulted is reduced drag, and in turn comparatively high take-off and landing speeds. The second Ro-II prototype set a world speed record on the 24th of September 1924, for 500 and 1000 km distances with a cargo load of 500 kg. The speed was 159 km/h, a 50% improvement of the record.

Test flight of the Ro-II resulted in the improved Ro-III flying boat. While the wings were identical, the fuselage was completely redesigned, with a new, more ship-like, bow and a step-keel, to better get out of the water during take-off. Incidentally, the modifications were designed by the young engineer Kurt Tank, who later became chief designer at Focke-Wulf. Several (possibly four) Ro-III aircraft were exported to Japan, who used them to study the new stressed-skin design technology.

An additional two (Ro-IIIa – with Dietrich engines) were delivered to Turkey during 1926. The Ro-III was also called the Rodra for ROhrbach DRei A. These were in active service until 1930.

The British were very keen on getting their hands on the new technology, and acquired, through the Beardmore company, a license to build the Ro-IV aircraft. The Ro-IV was very similar to the Ro-III, but used Napier Lion engines. To prevent the British public from knowing that the aircraft was in fact German, it was renamed the Beardmore Inverness flying boat. Beardmore never really mastered the stressed-skin technology and took five years to complete their first stressed-skin aircraft – the Bearmore Inflexible. Their recommendation to the Royal Aircraft Establishment was that biplanes were safer, and that all-metal aircraft were too heavy to be of any use.

The next design from the Rohrbach company was the Ro-V “Rocco” flying boat. This aircraft was designed in Berlin and manufactured in Copenhagen. However, since some of the restrictions of the Versailles treaty were lifted in 1926, more and more of the production took place in Berlin. The Ro-V Rocco had its maiden flight in 1927 in Copenhagen.

The construction of the Ro-VII “Robbe” was completed before the Ro-V “Rocco” and was a 6-seater flying boat. The aircraft had tapered wings and driven by two engines in a pusher configuration. A modified Robbe II was completed during 1927 and was to be used by Ernst Udet on his attempt at setting an Atlantic-crossing record. He crashed during a test flight, and the east-west Atlantic crossing was cancelled.

The Ro-VIII was a tri-motor aircraft. It was not a seaplane, and a total of 18 were designed and built in Germany.

The Turks, who were the only airforce actually using their Rohrbach aircraft, as opposed to using them to study stressed-skin construction, were very happy with the Ro-III’s and ordered 50 Rohrbach fighter aircraft. The fighter aircraft were named the Ro-IX Rofix. It was of a very advanced design, with a strutless parasol wing, armed with two 8mm machine guns, and powered by a 450 bhp BMW engine. The Ro-IX Rofix first flew during 1926, but the prototype crashed during a test-flight in January 1927. The second prototype crashed in June 1927, and the turks never took delivery of the aircrafts.

The Danish subsidiary company was shut down during 1927-1928. The buildings at Øresundsvej were torn down quite recently to make way to the new Øresund Metro station. After 1928, the Rohrbach company in Germany continued on its own, and went on to design and build the Rohrbach Ro-XI Rosta. It was a development of the Ro-II, and only a single unit was built.

During 1928-1929 Rohrbach was busy designing and building three Ro-X Romar prototypes. These large aircraft were designed for trans-atlantic passenger flight and sold to Lufthansa. They had to be taken out of service soon after they were put into service, after several serious accidents. The French ordered a single Ro-X Romar, most likely to study the stressed-skin construction methods pioneered by Rohrbach.

The German state had been subsidizing the German aircraft industry for years, and the company had to close during 1931/1932, as a direct result of the economic crisis in the country. The French Ro-X was Rohrbach company’s last order.

Hermann Göring visited Denmark

Hauptmann Hermann Göring (later Reichsmarschall Hermann Göring, head of the Deutsche Luftwaffe during WWII) visited Denmark twice after the Great War.

First time in a Fokker D.VII and later with a D.F.W. He was involved in an accident while in Denmark. A seagull flew into, and destroyed, the propeller on his D.F.W. after which he had to emergency land.

The D.F.W. he brought to Denmark was sold the the company “Nordisk Lufttrafik”.

Was Hermann Görings machine a DFW C.V? If you have more information (or a photo) of this aircraft, please leave a message.

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