J.Davilla, A.Soltan French Aircraft of the First World War (Flying Machines)

Societe des Etablissements Donnet-Denhaut

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  In 1912 Denhaut joined forces with Donnet, a Swiss engineer. Donnet evaluated Denham's design and, although he could offer no financial assistance, gave Denhaut a 50-hp Gnome, the resulting aircraft, intended initially for civilian use, was designated the Donnet-Leveque flying boat. The firm of Donnet-Leveque was established in 1912 to produce Denhaut's designs, and it built a racing version of this plane in 1913 powered by a 70-hp Gnome Y engine. A third flying boat was produced with an 80-hp Gnome 7A. Finally, a fourth version was produced in 1913, designated the Donnet-Leveque PD; the PD standing for Paris to Deauville (Deauville was a popular resort and it was Donnet-Leveque's intention to market (he plane as an ideal way to reach that city from Paris). Donnet left the company in 1913, and the firm's name was changed to Hydroplane Leveque. Another racer, produced by the Borel firm and designated the Borel PD, was built in 1913; it was equipped with a 100-hp Anzani 10c engine. Denhaut designed a second aircraft for Borel in the same year, a two-seat sport plane with an 80-hp Gnome and designated the Aeroyacht.
  Denham joined the army as a pilot in 1914. The authorities eventually realized that he could make a more valuable contribution to the French war effort by designing aircraft rather than simply flying them, and he was quickly released from military service.
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Donnet-Leveque Flying Boat Types A, B, C

  The Donnet-Leveque flying boat of 1912 was based on Denhaut's earlier flying boat built for Levasseur. It was a biplane with a crew of two. The upper wing was larger than the lower, and there was a single fin and rudder. The engine was a 50-hp Gnome. Designated the Type A, it had a concave hull with a prominent step and two stabilizing floats at the wing tips. The Type B was fitted with a 70-hp Gnome GN Y and ailerons. The Type C had an 80-hp Gnome 7A and an enlarged wing, enabling it to carry three persons. The Type A won the Belgian Coupe du Roi (King's Cup) for seaplanes in 1912. Although it was never used by the Aviation Maritime, the type did see service, albeit in altered form, during the First World War. The Type A was built under license by F.B.A. (See F.B.A. section.)


Foreign Service

Austro-Hungary
  The Donnet-Leveque flying boat was selected for evaluation by Austro-Hungary. The first to be obtained were Type As and Cs of 1912. Four aircraft were purchased in 1912. These were:
   Serial number 8: Type C purchased 17/12/12 and entered service 1/13.
   Serial number 10: Type A purchased 11/12/12 and entered service 4/1/13.
   Serial number 11: Type A purchased 11/12/12 and entered service 1/13.
   Serial number 12: Type C purchased 17/12/12 and entered service 1/13.
  The Austro-Hungarians were impressed by the aircraft and in 1913 three copies were produced by the Pola naval arsenal. These had Gnome engines, an enlarged fuselage, and longer wing span. Since more fuel could be carried, the endurance was increased from 3 to 4.5 hours. These aircraft were:
   Serial A 22: ordered 18/8/13 and entered service 18/3/14.
   Serial A 23: ordered 9/13.
   Serial A 24: ordered 5/13 and entered service 10/14.
  Aircraft S 26 was another copy built at Pola with a 50-hp Gnome engine. It was ordered on 20 May 1914 and entered service in August. S 2 and S 4 were also copies of Donnet designs and entered service in 1914. S 17 was a copy of the Type C and had an 80-hp Gnome engine; it had a longer fuselage but a shorter span than the Type A. The fates ol these aircraft are as follows: S 2 - unknown; S 4 - damaged April 1914; No.8 - struck off charge 2 September, 1913; No.10 - damaged in a crash 6 December 1913; No.11 - assigned to Pola and damaged 28 March 1913; No. 12 - struck off charge after being damaged in an accident 25 January 1913; S 26 - damaged 11 April 1915 and struck off charge 11 April 1915; S 22 - struck off charge in 1915; A 22 - struck off charge May 1915; A 23 - struck off charge May 1915; A 24 - struck oh charge May 1915.

Denmark
  The Danish air service obtained two Donnet-Leveque flying boats in 1913. They were initially stationed at the naval base at Klovermarken, where a hangar and slipway were built specifically lor them. A series of flying boats based on the Donnet-Leveque design was built by the Orlogsvaerftet naval dockyard. These aircraft was designed by H.P. Christensen and built by N.K. Nielsen. They were:
Aircraft Designation Number Built Period of Service
F.B.II 8 1914-19
F.B.Ill 10 1915-20
F.B.IV 2 1917-21
F.B.V 3 1918-21
  The Donnet-Leveque flying boats (which were designated F.B.1s) were used until 1915.

Russia
  A 1912 Donnet-Leveque flying boat was purchased by the Russians and delivered to St. Petersburg. It was flight tested in 1913. There are reports that some of the later versions of the craft were delivered to Russia, but these reports cannot be confirmed.

Sweden
  One Donnet-Leveque flying boat was purchased by the Swedish Marinens Flygvasende in 1913. It was assigned serial number S 22. A second aircraft was bought in 1914 and was given serial number S 23. S 22 was struck off charge in 1916; S 23 was given serial number 10 in 1917 and struck off charge in August 1918. Swedish Donnet-Leveque flying boats had these specifications: wing span ol 10.40 m;. length 8.50 m; wing area of 21 sq. m. and maximum speed ol 120 km/h.

United Kingdom
  England acquired a Donnet-Leveque seaplane (probably a Type C) in November 1912; it was the first flying boat to be used by the British armed services. Assigned serial H 7 (later No. 18) it was powered by an 80-hp Gnome. It was initially based at Eastchurch, then sent to the base at Grain in February 1913. It was struck off charge in June of that year, it having been noted that it had poor controls and was difficult to fly.


Type Engine Span Length Wing Area
A Gnome N1 9.0 m 7.80 m 18.00 sq. m
B Gnome Y 10.0 m 8.30 m 20.00 sq. m
C Gnome 7A 10.48 m 8. 30 m 22.00 sq. m

L.Opdyke French Aeroplanes Before the Great War (Schiffer)

H.King Aeromarine Origins (Putnam)

The first 'classic' type of flying boat, with the tail mounted directly on the hull, cannot, in fact, be credited to Curtiss at all, but to Denhaut, who constructed the Donnet-Leveque machine of this type in 1912.

Jane's All The World Aircraft 1913

DONNET-LEVEQUE.

   A 1912. B 1912. C 1912. 1913.
   2-seater 2-seater 3-seater 2-seater
   hydro- hydro- hydro- hydro-
   biplane biplane biplane biplane

Length......feet(m) 26 (7.80) 27 (8.30) 27 (8.30) 34? (10.50)
Span........feet(m) 29? (9) 32? (10) 34? (10.50) 29? (9)
Area....sq.ft.(m?.) 194 (18) 215 (20) 237 (22) 194 (18)
Weight...lbs.(kgs.) 683 (310) 772 (350) 888 (380) 888 (380)
Motor..........h.p. 50 Gnome 70 Gnome 80 Gnome 50 Gnome
Speed...m.p.h.(km.) 69 (110) 75 (120) ... 50 (80)
Endurance......hrs. ... ... ... ...
Number built
   during 1912 ... ... ... ...

Notes.--Lateral control by warping ailerons. Motor in gap just below upper plane: propeller in rear, direct driven. Fabric: "Aviator" Ramie.

Floats.--One large central boat 27 feet (8.20 m.) long--two small ones at each extremity of lower plane.

J.Forsgren Swedish Military Aircraft 1911-1926 (A Centennial Perspective on Great War Airplanes 68)

Donnet-Leveque

  Originally designed by F Denhaut as a pure flying boat, the airplane very quickly caught the attention of Mrss Donnet and Leveque. Further development resulted in the Donnet-Leveque A, the world’s first amphibian. Further development included the Donnet-Leveque B and C variants, which featured ailerons. After Donnet left in early 1913, the company became known as Hydroaeroplanes Leveque. Soon afterwards, Leveque joined forces with Louis Schreck. The basic Donnet-Leveque airplane proved the stepping stone for the FBA flying boats.
  Using some of the funds raised through the armored ship collection, one Donnet-Leveque amphibian ordered in 1913. The engineless airplane was delivered in October 1913, being transferred to the naval flight school at Oscar- Fredriksborg at Vaxholm, east of Stockholm. The 50 h.p. Gnome engine removed from the Nyrop No:3 was fitted to the Donnet-Leveque. The designation L I was issued to the amphibian, with the serial number S22 being assigned shortly afterwards. Apart from flight training, the amphibian was also based at Marsgarn in the Stockholm archipelago, and used for maritime reconnaissance. Wear and tear saw L I being withdrawn from use in April 1916.
  Prior to the delivery of L I, another Donnet-Leveque had been imported to Sweden. This particular airplane was bought in the summer of 1913 by Carl Cederstrom, who intended to use the amphibian at the state-supported Skandinaviska Aviatik AB flying school. (Although unsubstantiated in contemporary sources, it is believed that L I was originally intended for Cederstrom, but rejected by him as being underpowered.) Named Flygfisken (The Flying Fish), the airplane was flown from Malmen aerodrome, as well as nearby Lake Roxen.
  Although not confirmed, it may have been a Donnet-Leveque Type C, with the upper wing being fitted with ailerons. In late 1913, the amphibian was acquired by the navy for 10,000 kronor, eventually being taken on charge in February 1914. Designated L II and issued with the serial number S23 (later changed to 10), the amphibian was initially based at Marsgarn. It was later based at Gothenburg and Karlskrona respectively, before being struck off charge in August 1918, having accumulated just over 131 hours in the air. The Donnet-Leveque led a quite adventurous existence, being involved in several accidents. On May 14, 1914, Carl-Gustaf Krokstedt attempted to fly to the island of Gotland. Due to a broken oil pipe, Krokstedt was forced down in the Baltic Sea. He spent the next seven hours scooping water from the airplane before being rescued by a ferry. In 1915, the Donnet-Leveque was primarily used for flight training. Apparently, this was not very successful, as the amphibian was very heavy due to having become waterlogged.
  Two major accidents involving L II took place in 1916. On the first occasion, on May 11,1916, the hull ruptured during a heavy take-off, with the amphibian quickly overturning in the swells. The pilot, Arvid Flory, was making his first take-off in the Donnet-Leveque, had a lucky escape when he was thrown clear of the wreck. Being somewhat dazed, Flory nevertheless managed to climb onto the airplane. When the rescue boat arrived, the crew roared with laughter when they saw that the seat was still attached to Flory’s rear end. Flory later wrote of an interesting construction detail; the support wingtip floats were made out of papier mache. Repairs lasted for several months. The next accident, also involving Flory, occured on November 5, 1916, when the airplane overturned on take-off from Karlskrona. The third accident took place on July 26, 1917, when Lieutenant Sandstrom crashed at Nynashamn while taking off in foggy weather.
  This particular Donnet-Leveque has been preserved.

Donnet-Leveque Technical Data and Performance Characteristics
   Engine: 1 x 50 - 80 h.p. Gnome
   Length: 7,90 m
   Wingspan: 11,60 m
   Height: 2,90 m
   Wing area: 17,00 m2
   Empty weight: n/a
   Maximum weight: 560 kg
   Maximum speed: 108 km/h
   Armament:-


Preservation

Donnet-Leveque

  On September 15, 1919, the last of the two Donnet-Leveque amphibians, serial number 10, was donated to the National Maritime Museum in Stockholm. Along with the Nyrop No:3, the Donnet-Leveque was transferred to the National Museum of Science and Technology. The amphibian remained on public display from 1936 until April 1983, hanging from the ceiling of the museum’s Machine Hall. By 1983, it was in fairly poor condition. Following lengthy negotiations, the Donnet-Leveque was transferred to Flygvapenmuseum ownership in December 1997.
  In 2010, the volunteer Tullinge Group initiated a thorough restoration of the unique amphibian. Following restoration by Tullingegruppen, the Donnet-Leveque was put on display at Flygvapenmuseum on December 10, 2013.

E.Hauke, W.Schroeder, B.Totschinger Die Flugzeuge der k.u.k. Luftfahrtruppe und Seeflieger 1914-1918

Aufstellung der Flugzeuge bei den k.u.k. Seefliegern
8 Donnet-Leveque/F.B.A. Gn 80
10 Donnet-Leveque/F.B.A. Gn 50
11 Donnet-Leveque/F.B.A. Gn 50
12 Donnet-Leveque/F.B.A. Gn 80
A 22 Donnet-Leveque, Mickl/Arsenal Rh 85
A 23 Donnet-Leveque, Mickl/Arsenal Gn 80, Pr 100
A 24 Donnet-Leveque, Mickl/Arsenal Gn 80
S 26 Donnet-Leveque/Arsenal Gn 50
S 27 Donnet-Leveque/Arsenal Gn 80
S 2 Type Donnet-Leveque/Arsenal Neubau FI 85
S 8 Type Donnet-Leveque/Arsenal Neubau Gn 50

Журнал Flight

Flight, August 3, 1912.

BRITISH NOTES OF THE WEEK.

Paris to London in a Hydro-Aeroplane.

   ON the Donnet Leveque hydro-aeroplane Capt. Conneau, better known by his nom de vol of Andre Beaumont, started off from Juvisy on Friday last on a projected trip from Paris to London. He followed the Seine to Bezons, where he came down on the water after covering 36 miles. He intended to continue his journey along the Seine to Havre, cross the Channel, then keep round the English coast and up the Thames to Westminster, but the bad weather of the week-end has intervened and prevented any progress being made with this part of the programme.


Flight, August 17, 1912.

BRITISH NOTES OF THE WEEK.

Disaster Overtakes M. Beaumont.

   AFTER waiting for several days at Berons, a suburb six miles west of Paris, "Beaumont," otherwise Capt. Conneau, was able to make a start for London on the 9th inst. His Donnet-Leveque hydro-aeroplane was wheeled down to the water, and at 4.30 a.m. it rose from the Seine for a trial run. Everything was working in good order, so the pilot did not return but set his course along the Seine for Havre. Passing Meulan, Mantes, Vernon, Gaillon and Caudebec, the machine reached Quillebceuf at 6.40, where a stop was made for replenishments. A quarter of an hour later it was in the air again, and Havre was reached at five minutes to nine, the machine alighting in front of the Casino. The mechanics, hearing of the stop at Quillebceuf, had gone there, so that M. Beaumont had to rely on amateur help at Havre. Some slight damage was done through the machine colliding with the shore, but everything was in order after lunch when at 2 p.m. a re-start was made for Boulogne, to which a non-stop run of 1 hr. and 55 mins., without the slightest incident, ensued.
   At Boulogne the enthusiastic fishermen came out to render what assistance they could, but their zealous but unprofessional efforts only resulted in one of the floats being damaged, so that no further progress could be made that day. Repairs were, however, executed over night and on Saturday afternoon M. Beaumont prepared for the cross-Channel trip. The wind buffetted the machine very considerably and after making a circuit the pilot had to bring his machine down to the water, which was very choppy. Suddenly the biplane was caught by a very strong squall and completely overturned. The pilot was able to swim clear and superintended the towing of the wrecked machine back to the shore. It is to be repaired and M. Beaumont will then make another attempt to fly to London.


Flight, November 16, 1912.

THE PARIS AERO SALON.

Donnet-Leveque.

   The hydro-biplane shown on this stand is of rather more interest than usual, for it was one of the first machines of its type to meet with a measure of success, and for the fact that the British Admiralty have bought one of them. The one shown is of quite light build and is arranged as a two-seater, driven by a 50-h.p. Gnome. That supplied to our Navy was of much stronger and heavier build, equipped with an 80-h.p. Gnome and intended more for open sea work than for service on river or lake, or stretches of water where the surface does not get unduly disturbed. So that it may be used for atterrissage as well as amerrissage, it is fitted with a clever type of disappearing chassis which may be hauled up clear of the water by releasing a catch and turning a handle mounted at the rear of pilot's head. Perhaps our sketch will make this point clearer than would be possible by word description. The coque is built throughout of mahogany, which wood also enters into the construction of the tail in those parts which are likely to get splashed with or immersed in water. In front the section of the coque is rectangular, but aft of the main planes it takes on a section represented by a triangle standing on its base. There is a step in the float at a point just below the entering edge of the main planes. At the side of the body it is about 6 inches deep but in the centre it is considerably less, for the bottom of the hydroplane has the peculiarity that it is concave. Naturally there is no tail float in the accepted sense of the term for the coque itself acts in that capacity. There is, however, a small wooden plane, shaped more or less like a penguin's tail, which assists in getting the tail off the water when starting off. Inside, the coque is divided into watertight compartments, to eliminate the chance of it becoming completely flooded should it strike any hard obstacle and become punctured. Small egg-shaped floats are fitted to the tip of the lower planes to steady the machine on water. The engine is mounted in a position about two-thirds up the gap between the main planes, and provision is made so that the pilot may start it without leaving his cockpit.


Flight, February 8, 1913.

BRITISH-BUILT DONNET-LEVEQUE MACHINES.

   THE representatives of the Donnet-Leveque Hydro-aeroplane Company in England, Aeros, Ltd., of St. James's Street, W., are, we learn, forming a company to manufacture these well-known water flying machines over here. On the Continent they have met with a considerable measure of success, as is evident by the fact that, not long since, eight of these machines were ordered by the Austrian Government. One was delivered some few months ago to the British Admiralty. From the number of machines built for water flying that will ultimately be required for the defence of our country's coast we feel inclined to think that the proposed company should enjoy good business in a craft of this nature. When all details have been settled we hear that they intend to commence operations by establishing works and a flying school at Shoreham.
   Our sketch gives an idea of the general arrangement of the Donnet-Leveque hydro-biplane. The float, which supports the machine on the water, is extended right back to the tail, so fulfilling the double purpose of float and fuselage. It is built throughout of mahogany, and, inside it is divided into a number of watertight compartments in order that, should the coque become punctured by coming into contact with any hard obstacle it will not become flooded out with sea water. A peculiarity in the construction of the coque is that the hydroplane surface is concave on the under side, a feature which makes it particularly efficient as a skimmer over smooth water. The planes of the machine are built up cellule fashion and are mounted above the body at about one-third of its length from the nose. High up between them the engine is mounted, driving direct a propeller which, mounted in that position runs no risk of being broken by spray thrown up by the passage of the machine over the water. A special magneto and starting handle are fitted to the motor, so that it may be started by the passenger without any necessity for him to leave his seat in the cockpit. In order that the machine may be capable of landing on land as well as on water a special form of disappearing wheelbase is fitted, which, after the machine has left the ground may be wound up out of action by a handle operating a drum, arranged conveniently within reach of the passenger. Although the machine is strongly constructed, yet it is of quite light weight, for the 50-h.p. model does not weigh more than 682 lbs., while the 80-h.p. machine turns the scale at only 836 lbs.