Lavochkin La-5FN
Description
Role	Fighter
Crew	one, pilot
First Flight	March 1942 (LaG-5)
Entered Service	September 1942
Manufacturer	Lavochkin
Dimensions
Length	8.60 m	28 ft 2 in
Wingspan	9.80 m	32 ft 1 in
Height	2.540 m	8 ft 4 in
Wing area	17.5 m²	188 ft²
Weights
Empty	2,605 kg	5,731 lb
Loaded	3,265 kg	7,183 lb
Maximum takeoff	3,400 kg	7,480 lb
Powerplant
Engine	Shvetsov ASh-82FN
Power	1,380 kW	1,850 hp
Performance
Maximum speed	648 km/h	405 mph
Range	765 km	478 miles
Service ceiling	11,000 m	36,080 ft
Rate of climb	1,000 m/min	3,280 ft/min
Wing loading	186 kg/m²	38lb/ft²
Power/Mass	0.42 kW/kg	0.26 hp/lb
Avionics
Avionics
Armament
Guns	2x 20 mm ShVAK cannon
Stores	500 kg (1,100 lb) of bombs or up to 8 RS-82 rockets

The Lavochkin La-5 (Лавочкин Ла-5) was a Soviet fighter aircraft of World War II. It was a development and refinement of the LaGG-3 and was one of the Soviet Air Force's most capable types of the war.

The La-5's heritage began even before the outbreak of war, with the LaGG-1, a promising yet badly underpowered aircraft. The LaGG-3 was a modification of that design that attempted to correct this by both lightening the airframe and fitting a more powerful engine. Nevertheless, this was not enough, and the lack of power remained a significant problem.

In early 1942, two of the LaGG-1 and -3's designers, Semyon Lavochkin and Vladimir Gorbunov , attempted to correct this deficiency by experimentally fitting a LaGG-3 with the more powerful Shvetsov ASh-82 radial engine. Since the LaGG-3 was powered by an inline engine, they accomplished this by grafting on the nose section of a Sukhoi Su-2 (which used this engine). By now, the shortcomings of the LaGG-3 had caused Lavochkin to fall out of Stalin's favour, and factories previously assigned to LaGG-3 construction had been turned over to building the rival Yakovlev Yak-1 and Yak-7. 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.

When the prototype took flight in March, the result was extremely pleasing - the fighter finally had a powerplant that allowed it to perform as well in the air as it had been supposed to on paper. After flying, the LaG-5 (the change in name reflecting that one of the original LaGG designers was no longer with the programme), Air Force test pilots declared it superior to the Yak-7, and intensive flight tests began in April. After only a few weeks, the design was modified further, cutting down the rear fuselage to give the pilot better visibility.

By July, Stalin ordered maximum-rate production of the aircraft, now simply known as the La-5 and the conversion of any incomplete LaGG-3 airframes to the new configuration. 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 Eastern Front taking place at altitudes of under 5,000 m (16,400 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 flixed 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 La-7.

A number of La-5s continued in the service of Eastern Bloc nations after the end of the war, including Czechoslovakia.