The La-5's heritage began even before the outbreak of war, with the LaGG-1 and LaGG-3 aircraft. LaGG-3 was fitted experimentally with new Shvetsov Ash-82 radial engine in 1942. When the prototype took the ﬁrst ﬂight, the result was very pleasing. After ﬂying the LaG-5, Air Force test pilots declared it superiorto the Yak-7.
Maximum-rate production and the conversion of any incomplete LaGG-3 airframes to the new conﬁguration of the aircraft was ordered by July 1942. While still inferior to the best German ﬁghters at high altitudes, the La-5 proved to be every bit their match closer to the ground.
With most of the air combat over the Eastem Front taking place at altitudes of under 5,000 m (16,404 ft), the La-5 was very much in its element. Further reﬁnement of the aircraft involved a fuel-injected engine, further lightening of the aircraft, and fixed slats to improve all-round performance.
This was designated the La-5FN and would become the deﬁnitive version of the aircraft. Altogether, 9,920 La-5s of all variants were built, including a number of dedicated trainer versions, designated La-5UTI. Further reﬁnements of the aircraft would lead to the Lavochkin La-7.