The Ilyushin Il-2 Sturmovik was a ground-attack aircraft produced by the Soviet Union in large numbers during the Second World War.
The early two-seater prototype proved to be too heavy for the limited power of the early AM-35 engine.
A redesigned single-seat version was soon developed and saw combat, particularly in the early phase of the war in the Soviet Union.
While the Il-2 proved to be a deadly air-to-ground weapon, heavy losses were caused by its vulnerability to fighter attack.
Consequently, in February 1942, the two-seat design was revived.
The Il-2M, with a rear gunner under the stretched canopy, entered service in September 1942 with the surviving single-seaters eventually modified to this standard.
Later changes included an upgrade from 20 mm (0.79 in) to 23 or 37 mm (0.91 or 1.46 in) cannons, aerodynamic improvements, use of wooden outer wing panels instead of metal and increased fuel capacity.
In 1943, the Il-2 Type 3 or Il-2m3 came out with redesigned “arrow-wings” that possessed leading edges that were swept back 15 degrees on the outer panels, and nearly straight trailing edges, resulting in a wing planform somewhat like the AT-6 trainer.
Performance and handling were much improved from the resulting shift of the Il-2’s aerodynamic centre rearwards with the revised “arrow wing” planform to correct the earlier problem, and this became the most common version of the Il-2.
A radial engine powered variant of the Il-2 with the Shvetsov ASh-82 engine was proposed in 1942 to remedy projected shortages in the Mikulin inline engines.
However, the ASh-82 was also used in the new Lavochkin La-5 fighter which effectively secured all available engines to the Lavochkin bureau.
The radial engine Sukhoi Su-2 ground attack aircraft was produced in small quantities but was generally considered unsuitable due to inadequate performance and lack of defensive armament.
Variants
TsKB-55
Two-seat prototype, AM-35 engine, first flight on 2 October 1939.
BSh-2
VVS designation for TsKB-55 prototype.
TsKB-57
Single-seat prototype, AM-38 engine, first flight on 12 October 1940.
Il-2 (TsKB-57P)
Single-seat serial aircraft, AM-38 engine, first flight on 29 December 1940, some delivered to combat units in May–June 1941.
Renamed the Il-2 in April 1941.
Cannons 20 mm ShVAK or 23 mm VYa-23 (depending on which factory the Il-2 was manufactured in).
Il-2 two-seat
Two-seat version, AM-38 engine, first action on 30 October 1942 near Stalingrad.
Maximum bomb load reduced from 600 to 400 kg (1,300 to 880 lb).
Used on edges of flight formations for defence against German fighters.
Quickly replaced by the “Il-2 production of 1943”.
Il-2 production of 1943
Referred in the west as the “Il-2M”.
Powered by an upgraded AM-38F engine.
Delivered to the front units from early 1943. In 1943, the 20 mm ShVAK armed Il-2s faded out, leaving only the 23 mm VYa variant.
Il-2 with NS-37
Referred in the west as the “Il-2 Type 3M”.
Based on the two-seat Il-2, armed with Nudelman-Suranov NS-37 in conformal gun pods under the wings, instead of the 20/23 mm cannons, this version is an attempt to create an anti-tank aircraft, first used in combat during the Battle of Kursk.
However, the combat effectiveness was quite low, and production of the variant was limited to about 3,500.
Moreover, bomb load was decreased from 600 to 200 kg (1,300 to 440 lb). It was replaced by the conventional Il-2 attackers armed with cassettes with cumulative bomblets.
Referred in the West as “Il-2M3” or “Il-2 Type 3”.
As more duralumin became available for the Soviet aviation industry, the Il-2 received a set of all-metal wing panels.
At the same time, the outer wing planform was swept back, with a straight trailing edge, since the centre of gravity was shifted rearwards after the gunner was added.
The wing planform change regained controllability of the two-seat Il-2 back to level of the single-seat Il-2.
Il-2U
Training version, also known as UIl-2.
Il-2T
Torpedo bomber version for the Soviet Navy with the VYa-23 cannons removed to save weight, it was able to carry a single 45 cm (18 in) torpedo.
Evidently, it was only a design as the 23rd Attack Air Regiment of the Black Sea Fleet flew regular Il-2M-3s fitted with torpedo racks as a field modification, and that no such aircraft were ever noted in the battle sortie logs.
Il-2I
Armoured fighter, prototype only.
Concept based on several dogfights between Il-2 and Luftwaffe bombers.
Proved infeasible due to its low speed, which causes it to be able to intercept only older Luftwaffe bombers.
Il-2 with M-82
A backup project prepared while plants producing AM-35/AM-38 were evacuated.
Trials demonstrated that with the fighter engine, low-altitude performance and controllability were unacceptable.
Il-10
The Ilyushin Il-10 was a Soviet ground attack aircraft developed at the end of World War II.
It was also license-built in Czechoslovakia by Avia as the Avia B-33.
Initial production variant
Il-10M
Redesigned production variant
Il-10U
Two-seat operational trainer. Also known as UIl-10.