The Lavochkin La-5 was developed from the earlier LaGG-1 and LaGG-3 fighters, which suffered from too-heavy airframes and lack of a suitably-powerful engine. They were among the least popular fighters used by the V-VS during the Great Patriotic War and were known by a play on the aircraft designation which translated as “varnished guaranteed coffin,” which said everything one wanted to know about the deficiencies.

By late 1941, Stalin was commenting negatively on the LaGG-3 and the factories previously committed to the production of the LaGG-3 were turned over to Yakovlev for the production of the Yak-1 and Yak-7 fighters, which were notably superior designs. Motivated by fear of being imprisoned for sabotage by the NKVD for the failure of the LaGG-3, two of the designers - Semyon Lavochkin and Vladimir Gorbunov - decided to make a radical attempt at giving the fighter sufficient power, experimentally fitting a LaGG-3 with the Shvetsov ASh-82A radial engine. The design work required to adapt the LaGG-3 to the new engine and still maintain the aircraft's balance was undertaken by Lavochkin in a small hut beside an airfield over the winter of 1941-1942, all completely unofficially. Ultimately, Lavochkin accomplished his goal by grafting the nose section of a Sukhoi Su-2 to the narrow fuselage of the LaGG-3.

When the prototype took flight in March, 1942, the results were outstanding. The fighter finally had an engine powerful enough to perform well. The LaG-5 - the designation change noting that one of the original designers was no longer involved - was declared superior to the Yak-7, by the initial test pilots. Intensive flight tests began in April, and while the design was still inferior to German fighters at altitudes over 15,000 feet, it was faster than both the Bf-109 and the Fw-190 at altitudes below 15,000 feet and was more maneuverable than either German fighter at low altitude; given that nearly all air combat on the Eastern Front took place at altitudes under 15,000 ft, the new design was very much in its element. With the additional power of the new engine, armament was upgraded to two 20mm Berezin B-20 cannon, making it the most heavily-armed Soviet fighter. With the test results so good, Stalin ordered maximum-rate production in July, 1942. Known as the La-5 after the departure of Gorbunov, production also included conversion of incomplete LaGG-3 airframes to the new design configuration.

Before the La-5 went into production, a modified prototype had flown with a cut-down rear fuselage and an all-round vision canopy, similar to that of the Yak-1b. While the need was so great, the La-5 went immediately into production using the unfinished LaGG-3 airframes. In March 1943, production moved on to the La-5F, which featured the cut-down fuselage, with an ASh-82F (“Forsirovanny” - boosted) engine, which had the same output but gave improved performance at a higher altitude than the earlier Ash-82A. Top speed was 345 mph at sea level and 370 mph at 6,500 ft.; due to airflow limitations, the engine boost system could not be used above 6,500 ft.

The definitive La-5FN (“Forsirovanny Neprosredstvenno” - Directly Boosted) first left the factory on March 23, 1943. It is considered a parallel development of the La-5F rather than a successor, and both continued in simultaneous production through most of the remainder of 1943. The La-5F remained in service throughout the war. 9,920 La-5s of all sub-types were produced between 1943-45. La-5 losses were the highest of all fighters in the V-VS, except the Yak-1, with total losses of 2,591 during the war.

Kyril Yevstigneyev:

Kyril Yevstigneyev was born into a peasant family on February 17, 1917 in the village of Khokhly, Chelyabinsky Uyezd, Orenburg Governorate, in Russia's trans-Urals. He attended the Shumikhin elementary school before moving on to the Chelyabinsk industrial school where he trained as a fitter and on graduation went to work at the Chelyabinsk Tractor Plant where he joined the local aeroclub and got his first taste of flying.

Yevstigneyev joined the Red Army in September 1938 with the aim of becoming a pilot. He graduated from the Bijsk military pilot academy in the far-eastern Amur region in 1941, and was posted as a flying instructor to Serashevo. At the end of 1942 he was reassigned to Moscow, where he came to the attention of I. S. Soldatenko, who arranged for a posting to the front on March 17, 1943.

Yevstigneyev gained his first victories two weeks after his arrival at the front, shooting down a Bf-109 individually with a shared victory over a Ju-88 on March 28, 1943, near the village of Urazovo in Belgorod province, southwest of Moscow. On August 5, 1943 while flying a close air-support sortie in the vicinity of Belgorod, Yestigneyev's eight-aircraft formation engaged opposing German fighters. In the ensuing dogfight he was badly wounded in both feet and sent to a field hospital where he repeatedly argued with the surgeons not to amputate his feet. After nine days, he escaped from the hospital and made his way to the nearest airfield, a 35 kilometer hike on crutches, where he was able to get transport to his unit. While still on crutches, he managed to get back into combat flying; by the end of 1943 he had flown 144 sorties during which he scored 23 individual and three shared victories.

By August 1944 he was a squadron commander in the 240th Fighter Aviation Regiment when he was first awarded the Hero of the Soviet Union on August 2. He was awarded the British OBE in 1943, and a second HSU on February 23, 1945, by which time he was promoted to captain and made a squadron commander in 178th Guards Fighter Aviation Regiment. Yevstigneyev scored his 53rd and last aerial victory on March 26, 1945, a Fw-190 shot down over Budapest. By May 1945 he had been promoted to Major. Between March 1943 and April 1945 he flew 283 combat missions, engaged in 119 dogfights, and scored 53 solo and three shared aerial victories.

Kyril Yevstigneyev remained in the Red Air Force after the war. In 1966, he was promoted to Major General of Aviation, before retiring in 1972. He died in Moscow in 1996.