During the Great Patriotic War, the Soviet Il-2 attack aircraft became the most massive combat aircraft in the history of world aviation. More than 36 thousand of these machines were built, and this record has not yet been broken by anyone. Similar results were obtained for several main reasons. First, until a certain time, the Il-2 remained the only model of its class in our Air Force. In addition, it showed fairly high performance and was distinguished by good survivability even in the most difficult conditions.
As you know, the Il-2 aircraft had several unofficial nicknames, and one of the most famous is the "Flying Tank". The reason for its appearance was the unique ratio of firepower and protection of the aircraft. The latter was provided with a number of characteristic design solutions, first of all, a full-fledged armored body that protected vital units and built into the structure of the vehicle. Let's consider the booking of the Il-2 attack aircraft and evaluate its real capabilities.
Experimental aircraft BSh-2
Aircraft protection
Already during the First World War, the need to protect the pilot and vital aircraft components became obvious. Various attempts were made to equip equipment with hinged armored panels, but there was no particular increase in survivability. Later, as the technical characteristics increased, it became possible to install a more powerful reservation. In addition, the search for new solutions continued.
In the thirties, the idea of an armored corps appeared. She proposed to abandon the attachment of armor parts to the power set of the aircraft in favor of a full-fledged metal unit built into the frame. Several aircraft with such equipment were developed and even built in series. By the end of the decade, similar, but modified and improved ideas of this kind were used in a new attack aircraft project from the Soviet Central Design Bureau - BSh-2.
Central Design Bureau under the leadership of S. V. Ilyushin from the beginning of 1938 worked on a promising "armored attack aircraft". According to the main ideas of this project, the aircraft was to be equipped with a streamlined armored body, not just built into the structure, but forming the entire nose of the fuselage. It was proposed to build this unit from AB-1 aviation armor; all of its parts initially had a thickness of 5 mm - according to calculations, this was enough to protect against bullets of small arms of normal caliber and most of the fragments. Inside the hull, it was planned to place an engine and its attachments, gas tanks and two pilots.
IL-2 of the first production model with a single cabin
At the beginning of 1938, a preliminary version of the BSh-2 project was approved, and the staff of the Central Design Bureau began its further development. The engineers had to develop the necessary units corresponding to the technical specifications, and in addition, they had to take into account the peculiarities of mass production. As a result, while retaining its main features, the armored corps changed as it developed. The final appearance of the attack aircraft and its reservation was approved at the beginning of 1939. According to the current version of the project, it was planned to build a prototype.
During the first stages of testing, the armor of the BSh-2 aircraft was almost not finalized. The main attention of the designers at this time was paid to the power plant and auxiliary systems. However, in the spring of 1940, the leadership of the aviation industry recommended replacing the existing AM-35 engine with a newer AM-38. The use of a different motor made it possible to reduce the length of the armored hull, slightly reducing its weight. The weight reserve could be used to install an additional gas tank or reinforce armor.
As you know, in the summer and autumn of 1940, the BSh-2 project faced certain technical problems, due to which a proposal appeared to develop and build a single-seat vehicle with the most similar design. In the fall of the same year, an updated attack aircraft appeared, showing higher flight data. After the start of testing of this machine, on December 9, the project was assigned the IL-2 index.
Diagram of the Il-2 armored corps of the first modification
In the early spring of 1941, the Il-2 passed tests, according to the results of which the Central Design Bureau received a list of necessary improvements. Among other things, the military expressed their wishes in the context of the booking. Soon the fine-tuning was completed, and Soviet enterprises began to master the production of promising equipment. It should be noted that the presence of an armored body significantly complicated the process of building aircraft. For the manufacture of armor and the assembly of hulls, the program had to involve new enterprises that had not previously taken an active part in the construction of aircraft.
Corps evolution
The first in the series was the single-seat version of the Il-2 with an armored hull of the corresponding design. This hull had a characteristic shape and formed the nose of the fuselage with the engine compartment and the cockpit located above the center section of the wing. The body was assembled from sheets of homogeneous armor AB and cemented HD with a thickness of 4 to 12 mm. The parts were connected to each other using duralumin tapes and rivets, as well as bolts and nuts.
Experienced aircraft with a gunner's cockpit, providing maximum all-aspect protection
The engine received the least powerful protection. The entire hood, with the exception of the 6 mm so-called screw disk, made of 4-mm sheets of bent shape. The upper entrance to the water radiator tunnel was protected by a 7 mm thick piece; the oil cooler basket under the bottom was assembled from 6 and 8 mm thick sheets. The most serious protection was provided for the cockpit. The pilot's side was covered with 6-mm vertical sheets. The same protection was placed on the sides of the lantern. At the rear, the cockpit was covered with 12-mm panels of cemented armor. One of the gas tanks, covered with 5 mm armor, was located under the cockpit. The total mass of protective equipment reached 780 kg.
The metal armor was complemented by laminated glass. The canopy of the lantern was made of 64 mm glass. A similar detail of a different shape was installed on the rear lamp and provided an overview of the rear hemisphere. Side armored glass was provided next to the 6-mm armor of the sliding part of the lantern.
Since a certain time in the OKB S. V. Ilyushin, work was underway to create a new version of the Il-2 aircraft with two pilots. The experience of combat use has shown that the machine needs an air gunner and, as a result, its design needs to be reworked. After a long search associated with solving difficult design problems, the optimal version of the rear gunner's cabin was found, which has its own reservation. By the beginning of 1943, it was included in the updated armored hull, recommended for launch in the series.
Armor of the serial two-seat attack aircraft
The new cab was located in the place of the rear gas tank in the base body. Directly behind the pilot, a 12-mm armor plate was preserved, which now served as the front wall of the second cockpit. In fact, the shooter's own protection consisted of only one curved rear armored wall 6 mm thick, which occupied a significant part of the fuselage cross-section. Due to technical difficulties, the armored floor, sides and canopy with protection had to be abandoned.
The development of a hull with two cabins was associated with certain difficulties. First of all, it was necessary to do without a significant increase in the mass of the hull. In addition, the appearance of new metal assemblies behind the pilot's cockpit could lead to a change in centering - already causing complaints. However, through correct calculations and a few compromises, these problems were resolved.
Armor and survivability
The Il-2 attack aircraft is well known for its strength and combat survivability. These assessments are based on very specific objective indicators and data collected during the operation of equipment. The available data allow us to imagine the real effectiveness of the armor protection of the Il-2 aircraft and assess how useful the use of the full-size hull was.
Double IL-2 in flight
Perhaps the most complete and comprehensive statistics on damage and survivability of equipment are given in his monograph about the IL-2 by the outstanding Russian historian O. V. Rastrenin. He considered similar aspects of the attack aircraft service on the basis of data on damage to aircraft of the 1st, 2nd and 3rd assault air corps, 211, 230 and 335th assault air divisions, as well as the 6th guards assault regiment for the period from December 1942 to April 1944- th. First of all, the high survivability of the IL-2 is evidenced by the fact that 90% of the damage could be corrected by the forces of field workshops, and only 10% led to the sending of equipment to the rear or to write-off.
According to O. V. Rastrenina, in these compounds, 52% of the damage to the IL-2 was on the wing and tail, as well as their control systems. 20% of the damage was related to the fuselage as a whole. The engine and hoods suffered 4% damage, the radiators 3%, the cab and rear gas tank 3%. In only 6% of cases, the damage forced the pilot to make an emergency landing or led to breakdowns when landing on the airfield.
Bullets and shells did not pose a particular danger to the Il-2 armored hull and most often left only dents on it. Large-caliber bullets or shells from small-caliber guns, in turn, pierced the body of the aircraft and caused damage to its contents. Most often, the most serious damage affected the cockpit and gunner, rear tanks, oil cooler and propeller.
Assembly of attack aircraft at plant number 18 in Kuibyshev
In the book “Sturmovik IL-2. "Flying Tank". "Black Death" also mentions interesting statistics collected on the basis of a survey of decommissioned equipment. From the beginning of 1942 to May 1943, specialists studied 184 armored hulls at the cutting bases. It turned out that 71% of the hits of bullets and shells from fighters fall on the transverse armor elements. In this case, the main part of the shots was carried out from a limited sector of the rear hemisphere - almost clearly in the tail. Less than a third of the hits were on the longitudinal parts of the hull.
In the summer of 1942, tests were carried out to shell parts of the Il-2 hull from the German MG151 heavy machine gun. It was found that this weapon cannot penetrate the rear and side hull plates at distances of more than 100 m and at angles of more than 30 ° from the longitudinal axis of the aircraft. At angles less than 20 °, the side plates did not provide protection even when firing from 400 m. Interesting results were obtained with 12-mm cemented HD armor plates. Such a detail could withstand an armor-piercing bullet hit from a distance of 400 m, but only with a direct shot at it. If the bullet passed through the aircraft structure, oval-shaped gaps remained in the armor: after hitting the skin and internal parts, the bullet began to tumble and hit the slab sideways, which caused increased loads and neutralized the advantages of cementation.
The available data demonstrate an interesting feature of the IL-2 aircraft survivability over the battlefield. Only one fifth of all damage to the attack aircraft fell on the fuselage; the proportion of damage to the armored hull was even lower. To ensure the destruction of the vehicle by damaging the power plant, at least one or two precise hits of a small-caliber gun into the hood of the hull were required. In the case of the cockpit, even one well-aimed shot could be enough. Nevertheless, the likelihood of such a development of events was extremely small.
Spring 1945: IL-2 over Berlin
The specificity of combat use, design features and other factors led to the fact that the fuselage and armored hull received not the greatest amount of damage, being inferior in these indicators to planes. However, this fact does not mean that an armored hull is unnecessary. It is easy to understand that in the absence of it, the statistics of damage - including fatal ones - would look different. It should have been affected by the successful hits of anti-aircraft gunners and fighters in the unprotected engine and cockpit, immediately leading to the destruction of the attack aircraft.
In general, the Il-2 aircraft showed good combat survivability and maintainability. According to O. V. Rastrenin, in the 1st assault air corps from December 1942 to April 1944, 106 sorties accounted for each irrecoverable loss of an attack aircraft. Taking into account return losses, this parameter was reduced by more than half - to 40-45 sorties. Among other things, this shows how actively the restoration of damaged equipment was carried out with its subsequent return to service. However, the number of sorties per combat loss for different formations in different periods was seriously different. In the most difficult periods and in the most difficult sectors of the front, it did not exceed 10-15.
Armored deposit
It should be noted that the overall combat effectiveness of the Il-2 attack aircraft was based not only on armor and the achieved level of protection. The aircraft carried cannon and machine-gun armament, rockets and bombs, which made it a convenient and effective means of destroying enemy ground targets, including those on the front line of defense. Thanks to this, the IL-2 first became an addition to the existing bombers, and then took the place of the main strike vehicles of the Red Army Air Force.
IL-2 after restoration
From 1941 to 1945, several domestic factories built more than 36 thousand of these machines in total. During the Great Patriotic War, for various reasons, about 11, 5 thousand attack aircraft were lost. At the time of the victory over Germany, the troops had almost 3, 5 thousand aircraft, suitable for operation or capable of continuing service after repair. By the middle of the war, the Il-2 had become the most important element of the air force. Their share in the total fleet of combat equipment reached 30% and subsequently remained almost unchanged.
Unfortunately, the assault units constantly suffered losses. The pace of production and active combat use affected their size. During the war years, our country lost 11.5 thousand Il-2 aircraft. The combat losses among the pilots exceeded 7,800 people - more than 28% of all combat losses of the Air Force personnel. Nevertheless, before their death, the plane and the pilot managed to inflict significant damage on the enemy and make their contribution to the future victory.
In general, the Il-2 showed itself in the best way and significantly brought the victory in the war closer. The achievement of such results was facilitated by both the skill of the personnel and the perfection of the material part. The attack aircraft carried a variety of weapons, and in addition, it had unique protection against bullets and shrapnel. The armored hulls of the original design fully justified themselves and helped to defeat the enemy.
