Flight and tactical characteristics of LPL
Crew: 3 people. // Takeoff weight: 15,000 kg // Flight speed: 100 (~ 200) knots (km / h) // Flight range: 800 km // Ceiling: 2500 m // Number and type of aircraft engines: 3 x AM-34 // Takeoff power: 3 x 1200 hp // Max. add. excitement during takeoff / landing and diving: 4–5 points // Underwater speed: 4–5 knots // Depth of immersion: 45 m // Cruising range under water: 45 miles // Underwater autonomy: 48 hours // Propeller motor power: 10 h.p. // Duration of the dive: 1.5 minutes // Duration of ascent: 1.8 minutes // Armament: • 18-inch. torpedo: 2 pcs. • coaxial machine gun: 2 pcs.
The aircraft detects the enemy from the air and delivers a disorienting strike. Then, moving away from the line of sight, the car sits on the water and in a minute and a half plunges to a depth of several meters. The target is destroyed by a surprise torpedo strike. In case of a miss, the device rises to the surface in two minutes and takes off to repeat the air attack. A bunch of three such vehicles creates an impassable barrier for any enemy ship. This is how the designer Boris Petrovich Ushakov saw his flying submarine
Of course, such a project could not but appear. If there is an amphibious vehicle, why not teach the plane to dive? It all started in the 30s. Second-year cadet at the Higher Naval Engineering School named after V. I. F. E. Dzerzhinsky (Leningrad) Boris Petrovich Ushakov embodied on paper the idea of a flying submarine (LPL), or, rather, an underwater aircraft.
In 1934, he provided a voluminous folder of drawings along with a report to the department of his university. For a long time, the project “walked” through the corridors, departments and offices of the school, and was classified as “secret”; Ushakov more than once refined the submarine's scheme in accordance with the comments received. In 1935, he received three copyright certificates for various units of his design, and in April 1936 the project was sent to the Scientific Research Military Committee (NIVK, later - TsNIIVK) and at the same time to the Naval Academy. An important role was played by the detailed and generally positive report on the work of Ushakov, prepared by the captain of the 1st rank A. P. Surin.
Only in 1937, the project was endorsed by the professor of NIVK, the head of the department of tactics of combat weapons Leonid Yegorovich Goncharov: "It is advisable to continue the development of the project in order to reveal the reality of its implementation," the professor wrote. The document was also studied and approved by the head of the NIVK, military engineer of the 1st rank Karl Leopoldovich Grigaitis. In 1937-1938, the project nevertheless continued to "walk" along the corridors. Nobody believed in his reality. At first, he was included in the work plan of the "B" department of the NIVK, where, after graduating from the school, Ushakov entered the military technician of the 1st rank, then he was again expelled, and the young inventor continued to work on his own.
Winged submarine Donald Reid Commander-2
Developed with the participation of the US Navy in 1964, this submarine, in the form in which it is depicted in the diagram and illustration, never existed in reality.
Aquarium plane
The submarine aircraft gradually acquired its final appearance and "stuffing". Outwardly, the device looked much more like an airplane than a submarine. An all-metal vehicle weighing 15 tons with a crew of three was theoretically supposed to reach speeds of up to 200 km / h and have a flight range of 800 km. Underwater speed - 3-4 knots, diving depth - 45 m, swimming distance - 5-6 km. The aircraft was to be propelled by three 1000-horsepower AM-34 engines designed by Alexander Mikulin. The superchargers allowed the engines to perform short-term boost with an increase in power up to 1200 hp.
It should be noted that at that time the AM-34 were the most promising aircraft engines produced in the USSR. The design of the 12-cylinder piston power unit largely anticipated the development of aircraft engines of the famous Rolls-Royce, Daimler-Benz and Packard companies - only the technical “closeness” of the USSR prevented Mikulin from gaining worldwide fame.
Inside the plane had six pressurized compartments: three for the engines, one living room, one for the battery and one for the 10 hp propeller motor. The living compartment was not a cockpit, but was used only for scuba diving. The cockpit was flooded during the dive, as well as a number of leaky compartments. This made it possible to make part of the fuselage from light materials that were not designed for high pressure. The wings were completely filled with water by gravity through scuppers on the flaps - to equalize the internal and external pressure.
The fuel and oil supply systems were turned off shortly before full immersion. In this case, the pipelines were sealed. The aircraft was covered with anti-corrosion coatings (varnish and paint). The diving took place in four stages: first, the engine compartments were battened down, then the radiator and battery compartments, then the control was switched to underwater, and finally the crew moved to the sealed compartment. The aircraft was armed with two 18-inch torpedoes and two machine guns.
On January 10, 1938, the project was re-examined by the second department of the NIVK. Nevertheless, everyone understood that the project was "crude" and huge funds would be spent on its implementation, and the result could be zero. The years were very dangerous, there were massive repressions and it was possible to get under the hot hand even for an accidentally dropped word or "wrong" surname. The committee put forward a number of serious remarks, expressing doubts about the ability of Ushakov's plane to fly into the sky, catch up with the departing ship under water, etc. As a distraction, it was proposed to make a model and test it in a pool. There is no further mention of the Soviet submarine plane. For many years Ushakov worked in shipbuilding on ekranoplanes and ships on air wings. And only diagrams and drawings remained from the flying boat.
Submarine aircraft Conveir, 1964: This project could have become one of the most successful in the development of winged submarines, if not for the resistance of US Senator Allen Elender, who unexpectedly closed funding
Engine under the hood
A similar project to Ushakov in the United States appeared many years later. As in the USSR, its author was an enthusiast whose work was considered insane and unrealizable. Fanatical designer and inventor, electronic engineer Donald Reid has been developing submarines and creating their models since 1954. At some point, he got the idea to build the world's first flying submarine.
Raid assembled a number of models of flying submarines, and when he was convinced of their performance, he began assembling a full-fledged apparatus. For this, he mainly used parts from decommissioned aircraft. The first copy of the Reid RFS-1 submarine aircraft was assembled by Reid by 1961. It was registered as aircraft number N1740 and was powered by a 65-horsepower 4-cylinder Lycoming aircraft engine. In 1962, the RFS-1, piloted by Donald's son Bruce, flew 23 meters over the surface of the Shrewsbury River in New Jersey. It was not possible to carry out immersion experiments: serious design flaws affected.
To convert the aircraft into a submarine, the pilot had to remove the propeller and close the engine with a rubber cap, working on the principle of a diving bell. The tail housed a 1 hp electric motor. (for moving under water). The cockpit was not pressurized - the pilot had to use scuba gear.
A number of popular science magazines wrote about Reid's project, and in 1964 the US Navy became interested in it. In the same year, the second copy of the boat was built - Commander-2 (the first received the "military" name Commander-1). On July 9, 1964, the plane reached a speed of 100 km / h and made its first dive. In the first model of the aircraft, when submerged, the remaining fuel from the tanks was pumped into the reservoir, and water was pumped into the tanks to make the structure heavier. Thus, the RFS-1 could no longer take off again. The second modification should have lost this drawback, but it did not come to this, since the entire structure would have to be reworked. After all, fuel tanks were also used as diving tanks.
However, the design turned out to be too weak and light to be used for military purposes. Soon the leadership of the Navy lost interest in the project and curtailed funding. Until his death in 1991, Reid tried to "promote" his project, but did not succeed.
In 2004, his son Bruce wrote and published The Flying Submarine: The Story of the Invention of the RFS-1 Raid Flying Submarine. The RFS-1 itself is kept in the Pennsylvania Aviation Museum.
However, some sources claim that Reid's project has developed. The US Navy decided to build the Aeroship, a two-body aircraft capable of submerging under water. Allegedly in 1968, at the World Industrial Exhibition, this aircraft made a spectacular landing on the water, and then dived and ascended. However, the official program of that year's exhibition (held in San Antonio) did not include a demonstration of a submarine aircraft. Further traces of this design are lost under the heading "secret".
The unmanned submarine aircraft The Cormorant, developed by the Skunk Works (USA) and tested as a full-size model in 2006. All details about this project are hidden under the heading "top secret"
1960s underwater rock
In April 1945, a man named Houston Harrington suddenly appeared on the horizon, applying for a patent for "Combining an Airplane and a Submarine." The patent was received on December 25, but the matter did not go further. The Harrington submarine looked very beautiful, but nothing is known about its flight data or its underwater qualities. Subsequently, Harrington became famous in the United States as the owner of the Atomic-H record label.
Another patent for a similar design was obtained in the United States in 1956. It was created by the American Donald Doolittle (together with Reid). This design was repelled rather not from the aircraft, but from the submarine. Traditionally, movement under water was provided by an electric motor, but the flight was carried out using two jet engines.
In 1964, Conveir offered the US Air Force the development of a small submarine aircraft. Documents were presented - drawings, diagrams and even a few fantastic "photographs". Conveir received a technical assignment from the Bureau of Naval Armaments, which included a speed of 280-420 km / h, a diving depth of 460 m, a flight range of 555-955 km, etc. Despite the clearly overstated requirements, the contract was signed.
The project implemented Reid's idea of using fuel tanks as immersion tanks, but the fuel was not drained, but fed into other special tanks - for better distribution of the load under water. The living compartment and the engine compartment were sealed, the rest of the submarine was filled with water. In the manufacture of the submarine, it was planned to use ultra-light and ultra-strong materials, including titanium. The team consisted of two people. Several models were produced and successfully tested.
The denouement came unexpectedly: in 1966, the famous Senator Allen Elender, head of the Senate Arms Committee, openly ridiculed the project and ordered the development to cease. A full-size sample was never produced.
Border under lock and key
Inventors are in no hurry to create vehicles for two environments. The main problem is the high difference in density between air and water. While the aircraft should be as light as possible, the submarine, on the other hand, tends to be heavier for maximum efficiency. It is necessary to create completely different aerodynamic and hydrodynamic concepts for water and air. For example, wings supporting an airplane in the air only get in the way underwater. The strength of the structure also plays an important role and leads to a heavier aircraft boat, since such a unit must withstand very high water pressure.
Developed by Skunk Works, the Cormorant project is an unmanned floating craft powered by two jet engines. Cormorant can be launched from special underwater carriers - Ohio-class submarines. The Cormorant's underwater reserve is very small - only to get to the surface, and then, after completing a surface mission, return to the carrier. The drone's wings are folded under water and do not interfere with movement.
The body of the aircraft is made of titanium, there are no voids in it (they are filled with a material similar to foam), and the geometry of the body resembles a cross between a seagull and a Stealth.
Tests of individual systems of the "Baklan" were carried out, its reduced model was tested, as well as a full-scale model, devoid of some of the structural elements. But since 2007, information about the development of "Baklan" is practically absent, probably falling under the classic stamp of "top secret".
Submarine aircraft carriers
Of course, there were many projects similar in principle to submarine aircraft. The most characteristic - and fully realized - were the so-called "submarine aircraft carriers" - submarines carrying aircraft.
In 1942, the construction of such devices began in Japan, and in 1944, two aircraft carrier submarines I-400 and I-401 were launched. They carried three Seyran M6A specialized fighters. Light aircraft were launched on the surface of the boat using a catapult, the launch was carried out in 30 minutes. The aircraft could independently return to the ground base after the operation. However, there was a modification of the "Seyrans" without a chassis - for kamikaze. Their launch was easier, 14 minutes for everything. But the end of the war was approaching. The construction of the rest of the laid down boats (numbers 402, 403 and 404) was suspended due to the high cost of the project. "Seyrans" were made only 20 pieces. The cockpits of the fighters were pressurized in case they had to launch directly from under the water. In addition, two light submarines, I-13 and I-14, were manufactured to carry one fighter. The first combat "swim" of submarines was planned on August 17, 1945, but they did not reach the target, then it was postponed until August 25, and on September 2, Japan surrendered, and did not allow the ambitious project to come true. However, the Japanese managed to conduct combat tests of the small submarine-aircraft carrier I-25. In September 1942, a seaplane took off from a prototype of a similar boat and dropped two incendiary bombs in the forests of Ohio. The effect was practically nil: the forest fire did not start. But we can say that such designs were still used for combat purposes.
Submarine aircraft carriers were built not only by Japan. Back in 1928, the UK converted the HMS M2 boat for takeoff and landing of light seaplanes. The submarine sank in 1932, and a similar experience was never repeated in England. The only similar French attempt was the Pirate submarine, built in 1930 and sunk in 1942. In the USSR, in the 1930s, the development of special submarines for such purposes was carried out (series 14-bis). The planes for them were developed by I. V. Chetverikov (project SPL-1). A tiny plane could be prepared for take-off in just five minutes, and the container for it was a pipe with a diameter of 2.5 m and a length of 7.5 m. The aircraft was tested and set several international speed records in the small seaplane class, and was successfully demonstrated at the international air show in Milan in 1936. But after work on the carriers for Chetverikov's plane was discontinued (1938), the project lost its relevance.
In Germany, a similar project was developed in the years 1939-1940. The light aircraft Ar.231 V1 and Ar.231 V2 were designed. True, the long assembly time (10 minutes) and the incredibly difficult control of the resulting aircraft brought the project to naught. Another German attempt was the design of the Fa-330 reconnaissance gyroplane for take-off from a confined space, but this unit also performed poorly in tests.
