Dornier in the USSR
<…> When the decision to cancel the Junkers concession finally matured in late 1925, the USSR decided to buy Dornier seaplanes. A special memorandum explained:
We are extremely lacking in the sphere of hydroaviation. We not only are in need of aircraft (we have a miserly number of seaplanes) but also, and to a much larger extent, we need:
a) theoretical research (we have done next to nothing on hydrodynamics and hydroaviation, and have not published much in this area);
b) design experience in seaplane construction (very few flying boats have been built);
c) materials for underwater parts of wooden seaplanes (water-resistant adhesives, water-resistant plywood, varnishes, lacquers, and paints);
d) production skills;
e) production capacities (in plants and hydrodromes).
Meanwhile, the seaplane construction problem is very urgent and must be solved. Dornier has enormous experience with metal airplanes, especially seaplanes. Dr. Dornier himself and his closest assistants worked alongside Count Zeppelin, the famous designer of metal airships, and gained extensive experience in duralu-minum and mixed (steel with duraluminum) constructions.
... It would be extremely desirable for Aviatrust if the Dornier firm in one form or another is brought in to fill the gap in the seaplane construction sphere, taking into account that both the Aviatrust plants and the Central Aerohydrodynamic Institute (TsAGI) have achieved something in metal land-based plane construction.
The Dornier Wal seaplane was chosen for purchase. This flying boat, which Dornier designed in 1922, had a strong structure and good operational performance. It was a metal monoplane with two engines installed in tandem above the wing. Its smooth duraluminum skin set it apart from Junkers planes. The aircraft had a maximum take-off weight of 6350 kilograms, a maximum speed of 180 kilometers per hour, and a range of 2000 kilometers. The distinctive feature of this aircraft was two protrusions on each side of the hull (so-called "gills") instead of under-wing floats providing lateral stability. Thanks to its flat bottom, the airplane could if necessary take off from snow or ice. This predetermined R. Amundsen's choice of the Dornier Wal for his 1925 flight to the North Pole.
The USSR planned to employ this seaplane as a long-range reconnaissance aircraft and as a light bomber. The Air Forces leadership through the Soviet Embassy in Berlin requested that Dornier sell 20 flying boats in the summer of 1925. The Germans agreed immediately, submitting detailed information on prices, delivery terms, and aircraft technical specifications.
For a start, the Air Forces Directorate decided to buy two Dornier Wal aircraft and try them out. Both machines (No. 56 and No. 57) flew to Sevastopol' in autumn 1926. At the request of the Soviet military, the seaplanes was fitted with French Lorraine-Dietrich 12Eb 450hp engines each.
The metal seaplanes aroused much interest on the part of Soviet specialists. A group of TsAGI employees that institute director G. A. Ozerov headed went to Sevastopol' from Moscow as did P. D. Samsonov from the Experimental Naval Aircraft Building Department. GAZ-5 Samolet Production Plant personnel represented industry.
The seaplanes underwent considerable testing up to April 1927. A pilot named Rybal'chuk conducted the flights, as did V. K. Lavrov. Chief of Black Sea Naval Aviation. On the whole, test results were good: "Take off. Under normal atmospheric conditions on calm water it is simple and easy to handle. With elevators at the neutral position, it rises on the step. ...After lift-off, it is easy to maintain the required climb angle... In flight under normal conditions, the plane is stable, readily maintains the assigned attitude. A change in rpm has a minor effect on flight attitude. The plane does not yaw. If the load does not exceed 1500 kilograms, the plane can fly level on either engine. ...The landing is simple, easy to make..."
Lavrov's comments in his letter to Air Forces chief Baranov could be added to this: "The airplane has been very carefully made, the manufacture of the metal boat is incomparably better than that of Junkers. All important parts are easy to maintain and observe. Engine access is good. During flight the mechanic is located between them and can even do some repair work."
At the same time, a few shortcomings were noticed. Flight characteristics proved lower than claimed: speed by 10 kilometers per hour, ceiling by 900 meters, rate of climb to an altitude of 1 kilometer by 2 minutes. Perceptible engine vibrations were detected in flight.
A "conditional" decision was made to take delivery of these aircraft and to require the firm to eliminate the defects from the other planes. Dornier managers promised to fulfill this condition.
The Dornier firm and Soviet Joint Stock Company Metalloimport (the "front" for the Red Army Air Forces when buying German metal aircraft) signed a contract on April 22,1927 for deliver}' of 20 Wal flying boats and a set of spare parts for 10 such seaplanes. The Soviets ordered them with BMW VI instead of Lor raine-Dietrich engines because the former were more reliable, more fuel efficient, and delivered higher power as well. The aircraft were to be shipped to the USSR between October 1927 and May 1928. The order cost $875,150.
Since the Versailles Treaty prohibited Germany from building aircraft of the Dornier Wal type, the seaplanes ordered were produced at a
Dornier plant in Marina-di Pisa, Italy. They then went by sea to a Black Sea port. The airplanes came without engines, which were bought separately from BMW. R. L Bartini, at that time an engineer from one of the Black Sea squadrons, participated in the aircraft acceptance and assembly process.
Two squadrons—the 60th and 63rd based in Holland Bay in Sevastopol'— were formed from these airplanes. Two Wals were transferred to Baltic Fleet Aviation as part of the 66th Aviation Detachment located in the Leningrad Rowing Port. Vibrations during flight were significantly reduced thanks to use of new engines and propellers. By agreement with the Dornier firm, the seaplanes were fitted with new bomb racks allowing two 250-kilogram bombs to be suspended below the "gills".
Later, Soviet Russia bought one more consignment of Dornier Wal seaplanes. Beginning in 1930, they were purchased without engines and then fitted with the M-17 engine (domestic version of the BMW VT). According to V. B. Shavrov's data, the Sevastopol' Repair Plant produced six more Wa airplanes using imported components." They were the first domestically produced airplanes skinned with smooth metal.
The Dornier flying boats remained in the Soviet Naval Aviation inventory until the mid-193Os, then were replaced by TB-1P floatplanes and domestic MBR-2 flying boats. Before that, the Dornier Wal was considered the best airplane in Soviet Naval Aviation.
The Dornier Wal was also used for passenger and cargo transportation along Siberian rivers. The machine played a major part in exploration of the Far North of the country, the first Wal appearing there in 1928. The Dobrolet Joint Stock Company had bought it. Named Mossovet, the aircraft flew the Irkutsk-Yakutsk route and carried 135 passengers and 2500 kilograms of mail in the winter of 1928-1929. A G. D. Krasinskiy-led polar expedition used another plane called Sovetskiy Sever in 1928. The plan was to fly via the Northern Maritime Route from Vladivostok to Leningrad but, at the halfway point, the flight had to be interrupted when a sudden storm damaged the anchored boat's power plant. S. V. Obruchev employed a Dornier Wal N-1 on a 1932 geological expedition.
Then, for the first time, a transit flight was made from Krasnoyarsk throughout Siberia, the Amur region, and the Sea of Okhotsk to Vrangel' Island.
Famous polar pilots such as B. G. Chuchnovskiy, V. S. Molokov, and others made reconnaissance flights in Dornier flying boats and showed the way for ships. During the 1929-1930 navigation, Wal fliers managed to pilot more than 50 vessels through polar ice. B. G. Chuchnovskiy wrote at the time: "Judging by experience from the 1929 flights, the two newly-built airplanes with modern improvements are the best among those serving here and abroad for work in the Arctic."
A special "arctic" version of the Dornier Wal was developed in the USSR. At Chuchnovskiy's suggestion, the boat's bottom was strengthened, the fuel pipe design changed, and an emergency fuel jettisoning system developed. This modified version was produced at the Altenrhein Plant in Switzerland based on an order we placed.
Dornier Wal seaplanes were in service with the Northern Fleet and Polar Aviation until the onset of the Great Patriotic War. Thanks to their design features, they were distinguished for their high strength and their "all-terrain" capabilities, if it can be put this way. V. R. Kotel'nikov provides this example: "In summer 1940 M. N. Kaminskiy made a forced landing right in the tundra, failing to make it to water. After minor repairs, having brought the machine up to speed along an oiled wooden platform, the pilot managed to take off."
The designs of some Soviet seaplanes reflected the experience operating Dornier Wal flying boats. The DAR arctic reconnaissance seaplane, built at the State Air Fleet Aircraft Scientific Research Institute in 1935 at the initiative of B. G. Chuchnovskiy, with participation of German engineers W. Fuchs and E. Gra, had such distinctive Dornier aircraft features as the raised wing, flat-bottom hull, and wing-mounted tandem engines. It is also known that research into the special aerodynamic features of the power plant and boat line arrangement was carried out at TsAGI in the early 1930s.
- "The German Imprint on the History of Russian Aviation " /D.A. Sobolev, D.B. Khazanov/