Aviation of World War II
Torpedo Bombers of the USSR and Germany
Torpedo-carrying aircraft, which appeared during the First World War, quickly established itself as a fairly effective means of combating enemy surface ships. In addition, due to the significant carrying capacity, torpedo bombers could be used as bombers, reconnaissance, minelayers or anti-submarine. I must say that recognizing the torpedo bombers as a very important combat weapon, the designers did not try too hard to improve their flight data. For a long time, the bulk of this class of aircraft was represented by braced biplanes, among which the Soviet twin-engine monoplane TB-1 designed by A.N. Tupolev looked like a beautiful swan among a flock of ducks.
The situation began to change in the mid-30s, when it became clear that with the further improvement of naval artillery and fire control devices, it would be increasingly difficult for destroyers to attack enemy squadrons and convoys with torpedoes at the transition. And although during the years of the Second World War that began soon, British, German and Japanese "destroyers" happened to inflict heavy losses on the enemy with their torpedo salvos, it nevertheless became obvious that destroyers, in football language, were retraining from attackers to defenders. At the same time, there was nothing to fully replace them in this role.
The torpedo boats that existed then could only successfully operate in coastal areas, since they had significant limitations in terms of range and meteorological conditions. Submarines had serious chances of success, but they could not pursue surface ships in the ocean, due to the low surface and underwater speeds. At the same time, the need for quick and effective strikes was not in doubt.
In the prevailing conditions, it became obvious that only aviation could be capable of this. But even here there were a lot of unresolved problems, since, as American experiments with the captured German battleship Ostfriesland showed, bombing even stationary ships from level flight leads to a significant number of misses. It was almost impossible to get into the maneuvering ship. Of course, the idea of creating dive bombers was already in the air, but it was still quite far from its actual implementation. Thus, only torpedo bombers remained.
Almost at the same time, the creation of the base strike aviation of the Soviet navy began, the command of which pinned considerable hopes on the adoption of the Tupolev SB and the DB-3 long-range bomber designed by S.V. into service with the Red Army Air Force. Ilyushin. It should be noted that the creation of the latter took place in conditions of intense competition with the brigade of P.O. Sukhoi, who developed (under the general supervision of A.N. Tupolev) the long-range bomber DB-2. The situation was further aggravated by the fact that both aircraft were designed for the new M-85 two-row star-shaped engines (the licensed Mistral-Major 14Kdrs engine, developed by the French company Gnome-Ron), which developed 850 hp during takeoff.
With a generally identical layout of the fuselages of their future aircraft, due to a single TTZ, both design bureaus solved the problem of achieving a given flight range in completely different ways. A certain conservatism of the head of the "company" - A.N. Tupolev, who considered that the traditional use of a wing with a low specific area load and a large geometric aspect ratio on a heavy aircraft would reduce the inductive drag and increase the range. Capacious gas tanks, which were easily placed in huge consoles, also contributed to its growth.
S.V. Ilyushin believed that the given range could be achieved with a moderate span wing, which had a fairly high area load. At the same time, he proceeded from the fact that the share of inductive drag in the total drag balance depends primarily on the wing lift and decreases at low angles of attack, typical for speeds of 350-400 km/h. True, at the same time, the proportion of profile drag increased, but it was possible to reduce it by using a thin biconvex profile, as well as by a general reduction in the wing area.
As a result, with the same specified armament (three 7.62-mm ShKAS machine guns and 1000 kg of bombs on the in-fuselage suspension) and range (4000 km), the "troika" surpassed the "two" in cruising speed by almost 1.5 times , showing on the route 310-320 km / h against 210-220 km / h. The superiority in maximum speed was also noticeable - 400 km / h versus 340 km / h. By the way, according to this parameter, the DB-3 took an honorable third place among Soviet vehicles after the I-16 and SB! Considering, moreover, that the maximum payload of the Ilyushin bomber was 25% higher than that of the Tupolev bomber (2,500 kg vs. command of the Red Army Air Force and the leadership of the People's Commissariat of the Aviation Industry (NKAP), who decided to launch mass production and adopt the DB-3.
However, there was a price to pay for all these achievements. By and large, there were only two major shortcomings. Firstly, in the bomb bay, squeezed by spars, it was impossible to hang anything larger than "hundredths", which, incidentally, corresponded to the TTZ. However, when the creation of the DB-3T torpedo bomber began in 1937, this drawback became obvious: the aircraft torpedo 45-36AN was lifted only on an external sling, which significantly reduced speed and range. Secondly, the alignment of the new aircraft was 32-33% of the mean aerodynamic chord (MAC), which caused extraordinary control sensitivity and disgusting stability. The car in the full sense "hung on the handle" and the slightest weakening of control over its behavior threatened to stall.
For long-range bomber crews, this unpleasant feature of the aircraft was dangerous when returning, when the task was completed and the pilot could relax. Only the appearance in 1942 of the autopilot slightly smoothed out this shortcoming. For torpedo bombers, the main troubles began when they went on the attack. The erratic aircraft roamed its course and altitude, additionally affected by ground turbulence and shell explosions that tossed it like a piece of wood. Very few people managed to carry out aiming under these conditions, and most importantly, to stay in level flight at a height of 30 m at the time the torpedo was dropped. As a result, most of the dropped torpedoes either burrowed into the water or broke from an oblique impact on its surface. In addition, the developed suspension system for the DB-3T, which theoretically ensured that the torpedo entered the water at the right angle, was cumbersome and imperfect. Torpedoes were not always separated from aircraft. All this led to the fact that by the beginning of hostilities, a small number of crews could master low torpedo throwing, and the elimination of technical flaws continued in parts of mine-torpedo aviation throughout the war and after it ended.
The torpedoes themselves were not of high quality, they were not the best copy of the Italian one. Suffice it to say that even after the end of the war, during the tests, the low reliability of torpedoes was noted, up to 20% of which did not meet the declared characteristics (did not pass the established distance) or simply failed (sank at the splashdown point). As for the striking characteristics of domestic torpedoes, they were perhaps the worst, which, apparently, was due to the low quality of the explosives used. Aviation torpedoes were also armed with torpedo boats of the Soviet Navy, which, although less rich, but also not too “pleasant” experience in their use than aviators. For example, on April 16, 1945, the German destroyer "Z-34" received one such "fish", but, despite the explosion, was able to successfully reach the base under its own power (!)
A noticeable step forward could be the long-range bomber Yer-2, which had higher performance compared to the DB-3F. Suffice it to say that four 500-kg bombs (!) were placed in its capacious bomb bay, and this at a significantly greater range (about 5000 km) and speed (up to 475 km / h). A further increase in the payload mass (up to 6000 kg) and the transition to diesel engines would make it possible to create a fairly powerful torpedo bomber. I must say that the structural strength and survivability of the diesel Yer-2 was very high, because kerosene is much less flammable than gasoline. Ermolaev's bomber was more stable and could fly even "with the handle thrown". However, at that time, the possibility of using the Yer-2 in the interests of the fleet "at the top" was not even considered, and therefore the main torpedo bomber in the aviation of the Navy for a long time was the DB-3T and its development Il-4T, only starting from 1943 they were noticeably pressed by the received under the "Lend-Lease" "Boston".
Not everything went well with the creation of torpedo-carrying air units in Germany, whose aviation is generally considered to be the most prepared for the start of World War II. The reasons for this lay in the unimaginable scale of the rivalry between the Luftwaffe and the Kriegsmarine. The command of the latter, in the course of lengthy battles "under the rugs" of the Reich Chancellery, managed to get under operational control the so-called VI Luftwaffe Air Command, which included coastal air groups.
While these units were armed with Do-18 flying boats and He-59 float biplanes (the adoption of the latter as torpedo bombers was entirely the merit of the fleet), the Air Force command was rather calm about this "victory of woodlice from Raeder's headquarters." However, the He-59 was soon superseded by the more modern He-115 hydroplane, which for a fairly short time became the main German torpedo bomber, and that, in turn, became the He-111 and Ju-88 coastal-based vehicles. From that moment on, the main headquarters of the Luftwaffe did not stop trying to take away from the fleet what did not belong to it by its nature - wheeled coastal-based aircraft.
NKAP - Narodnyy komissariat aviatsionnoy proomyshlennosti - People's Commissariat of Aviation Industry
TTD - Taktiko tekhnicheskiye dannyye - Tactical technical data
TTZ - taktiko tekhnicheskoye zadaniye - Tactical terms of reference
VVS KA - Voyenno vozdushnyye sily Krasnoy armii - Air Force of the Red Army
Ил-4 Торпадоносец - IL-4 Torpedo Bomber
* Maximum speed without payload and half fuel.
It is clear that after such a plot, the interest of Goering's department in torpedoes was met with very hostility by the sailors. The headquarters of the leadership of the war at sea, in fact, sought to retain the right to form torpedo-carrying units and therefore very energetically “put a spoke in the wheels” of the Air Force, trying to prevent aviators from getting information about work in the field of torpedo weapons.
By this time, the He-111 was adopted as the main bomber in the Luftwaffe, successfully tested in the blazing sky of Spain. Modifications of the He-111E-3, E-4 and E-5 descended from the assembly lines of several enterprises, which were all-metal twin-engine monoplanes with retractable landing gear, an enclosed cockpit and two bomb bays for 2000 kg of bombs, and, unlike the DB-3, they could accommodate eight 250-kg land mines. Instead of the left bomb bay, the Pyaterka had additional gas tanks with a total capacity of 830 liters, which increased the range from 1500 to 2000 km, and external universal bomb racks. As a power plant, all used 12-cylinder in-line liquid-cooled engines Jumo211A-1, which developed 1000 hp in takeoff mode. s., and at an altitude of 1500 m -960 l. With. Thanks to them, the bomber accelerated at an altitude of 4000 m to 420 km / h. Defensive armament - three 7.92 mm MG15 machine guns.
With a lot of undoubted advantages, the "one hundred and eleventh" early series had one significant drawback - the elliptical wing, which had excellent bearing qualities and low resistance, required significant costs in production, which to a large extent slowed down mass production. New planes with the same characteristics, but having straight edges and therefore more technologically advanced, were tested back in 1936 on the He-111G, but the Technical Directorate was in no hurry to accept the novelty, fearing a decrease in the number of aircraft produced.
It is not known how long this innovation would have lay "under the cloth" if Turkey had not ordered a batch of He111F-1 bombers, which differed from the E-5 modification in new consoles and Jumo 211A-3 engines with a capacity of 1100 hp.
Meanwhile, by the summer of 1938, the long-awaited DB600 engines were finally received, and the Luftwaffe command began to think about creating "its own" torpedo-carrying units. The He-111F-4 was adopted as the basic version for the He111J-0 torpedo bomber, some of which nevertheless ended up in the Luftwaffe at the height of the Munich crisis. The only difference between the “null” was the weight models of two torpedo bridges and torpedoes, moreover, the latter could not even be dropped! Although the plane flew successfully, it was accepted into service as a ... bomber. The lack of necessary documentation forced the abandonment of the production of torpedo bombers, but not for long.
Taking advantage of the "torpedo crisis" that broke out in the spring of 1940, the assertive Goering achieved the transfer of one of the main accused, Dr. Oskar Vera, one of the leading designers of German torpedo weapons, directly from under investigation to his department. This paid off: already in the autumn of the same year, He-111H-4 torpedo bombers began to arrive in service with II / KG26 in small quantities. However, in 1941, the He-111H-6 variant was adopted as standard, which had Jumo211F-1 engines that developed 1400 hp in takeoff mode. With. and 1200 l. With. at an altitude of 5000 m. Two F5b torpedoes on universal PVC ventral holders could easily be replaced with large-caliber bombs. Another 1000 kg could be placed in the right bomb bay. The aircraft carried six to seven MG15 machine guns, and the front one at the navigator and one of the two lower ones (pointing forward) were soon replaced by 20-mm MG FF cannons, designed to suppress anti-aircraft fire. The domestic press has repeatedly pointed out the superiority of the Ilyushin Il-4 over the He-111. However, with the exception of a longer range and comparable speed data, the Soviet bomber in all other indicators (especially in flight) was noticeably inferior to the German car.
However, if it was not difficult to create a modern torpedo bomber, then the torpedo weapons with which Germany entered World War II can hardly be called reliable enough. Hydrostats worked disgustingly, because of which torpedoes did not keep depth well, and non-contact electromagnetic fuses, with the help of which, as it seemed, it would be easy to “break the ridges of British battleships”. On the eve of the outbreak of hostilities, the percentage of failures was estimated at almost 50%, which forced the Italian W torpedo to be adopted at the end of 1941. Later, based on its design, the German F5b torpedo was upgraded, which received another gyroscope, an additional Aubrey device and a cylindrical insert with additional rudders to improve entry into the water. Ultimately, the quality of the weapons returned to normal, and this allowed the German torpedo bombers to achieve impressive success against the Arctic and Mediterranean convoys.
Retrospectively evaluating the level of development of torpedo-carrying aviation on the eve of the Second World War, it becomes obvious that the indisputable leadership in this area of the Land of the Rising Sun, which managed not only to create perfect aircraft and torpedoes, but also to form aviation formations, staffed by flight personnel who underwent good flight training and received combat experience. This achievement is all the more surprising because even ten years ago, the Japanese industry had no experience at all in creating multi-engine all-metal combat aircraft. Western historians explain this phenomenon in different ways. It is widely believed that Japanese aircraft designers were not weighed down by the burden of tradition and did not lack funds. However, these factors did not ensure success. Its reasons lay in the unprecedented independence of the Imperial Navy, which had the full right to order the industry precisely those models of military equipment (including aircraft) that made it possible to carry out the tasks set by politicians to the maximum extent.