The word shturmovík (Cyrillic: штурмовик), the generic Russian term for a ground-attack aircraft, became a synecdoche for the Il-2 in English sources, where it is commonly rendered Shturmovik, Stormovik[3] and Sturmovik.

The prototype TsKB-55, which first flew on 2 October 1939,[8] won the government competition against[citation needed] the Sukhoi Su-6 and received the VVS designation BSh-2 (the BSh stood for "Bronirovani Shturmovik" or armoured ground attack).

The BSh-2 was overweight and underpowered, with the original Mikulin AM-35 1,022 kW (1,371 hp) engine designed to give its greatest power outputs at high altitude.

Because of this, it was redesigned as the TsKB-57, a lighter single-seat design with the more powerful 1,254 kW (1,682 hp) Mikulin AM-38 engine, a development of the AM-35 optimised for low-level operation.

[citation needed] Competitive tests were conducted in the spring of 1941 between the MP-6 gun modified to belt-fed and the newly developed, gas-operated Volkov-Yartsev VYa-23, which had otherwise rather similar characteristics.

[14] The Il-2 is a single-engine, propeller-driven, low-wing monoplane of mixed construction with a crew of two (one in early versions), specially designed for assault operations.

[12][15] Production early in the war was slow because after the German invasion the aircraft factories near Moscow and other major cities in western Russia had to be moved east of the Ural Mountains.

Instead of a low horizontal straight approach at 50 metres (160 ft) altitude, the target was usually kept to the pilot's left and a turn and shallow dive of 30 degrees was used, using an echeloned assault by four to twelve aircraft at a time.

The aircraft could fly in low light conditions and carried weapons able to defeat the thick armor of the Panther and Tiger I tanks.

[24] In another report of the action on the same day, a Soviet staff publication states that: Ground forces highly valued the work of aviation on the battlefield.

In fact, total German tank losses in Operation Citadel amounted to 323 destroyed, the vast majority by anti-tank guns and armored fighting vehicles.

[27] In addition, it is difficult to find any first-hand accounts by German panzer crews on the Eastern Front describing anything more than the occasional loss to direct air attack.

The 17th Panzer did not register any abnormal losses due to aircraft in the summer of 1943, and retreated westwards with Army Group South later in the year, still intact.

[citation needed] In the 9 June offensive in the Karelian Isthmus in Finland, Finnish anti-aircraft forces were far too few in number to counter the armadas of Pe-2 and Il-2, but quickly found that the Il-2 attacks generally missed their marks widely, particularly with bombs.

[citation needed] To compensate for the poor accuracy of the Il-2's bombsight, in 1943, the Soviet Command decided to use shaped-charge armor-piercing projectiles against enemy armored vehicles, and the PTAB-2.5-1.5 SCAP aircraft bomb was put into production.

[citation needed] While the fabled 88 mm (3.5 in) calibre gun was formidable, low-flying Il-2s presented too fast-moving a target for the 88's relatively low rate of fire, only occasional hits were scored.

Similarly, Finnish attempts to counter the Il-2 during the summer of 1944 proved ineffective as a result of the low numbers of 20 and 40 mm (0.79 and 1.57 in) AA in the field army.

[32] [page needed] The armored tub, ranging from 5 to 12 mm (0.20 to 0.47 in) in thickness and enveloping the engine and the cockpit, could deflect all small arms fire and glancing blows from larger-caliber ammunition.

[36] The second cockpit and armament increased all-up weight by 170 kg (370 lb) so the flaps were allowed to be deployed at an angle of 17° to avoid an over-long takeoff run.

The Shturmovik rear guns proved to be effective against hostile fighters, and during the service trials alone, gunners shot down seven Bf 109s and repulsed many attacks.

The need to shift the aerodynamic center of the aircraft forwards due to the weight of the added rear gunner and lengthened cockpit was the reason for the swept back outer wings in later Il-2s.

[38] In February 1945, the highest scoring German flying ace to be killed in action, Otto Kittel, was shot down by return fire from an Il-2.

[citation needed] While outclassed by dedicated fighters such as the Messerschmitt Bf 109 and Focke-Wulf Fw 190, in dogfights, the Il-2 could take on other Luftwaffe aircraft with some success.

[40] While the Il-2 was a strong air-to-ground weapon, and even a fairly effective interceptor against slow bombers and transport aircraft, heavy losses resulted from its vulnerability to fighter attack.

[42] One of these awards was the Gold Star of Hero of the Soviet Union that Yegorova had received "posthumously" in late 1944, since she was presumed dead after being shot down.

To his surprise, a German Bf 109 fighter landed near the crash site and the pilot began to investigate the wrecked Il-2, possibly to look for souvenirs.

On his final sortie in Liepāja, Latvia on 14 December 1944, his plane was hit by anti-aircraft fire, and although wounded, he flew his airplane into a German warship.

Soviet sources assert that Stepanyan flew no fewer than 239 combat sorties, sank 53 ships, thirteen of which he did alone, destroyed 80 tanks, 600 armored vehicles, and 27 aircraft.

Performance and handling were much improved from the resulting shift of the Il-2's aerodynamic center rearwards with the revised "arrow wing" planform to correct the earlier problem, and this became the most common version of the Il-2.

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.