The Lavochkin La-5 aircraft was a re-working on the Lavochkin-Gorbunov-Goudkov group's previous fighter, the LaGG-3. It would eventually lead to the development of the La-7, one of the most capable Soviet fighters of the war.
The LaGG-3 was an unpopular design among its pilots. Attempts to fix the power problem of the LaGG-3 were somewhat successful, but eventually Lavochkin would fall into disfavor with Stalin, and many of the factories dedicated to production of Lavochkin machines were turned over to the competing Yakevlov group.
Semyon Lavochkin and Vladmir Gorbunov continued to work on the LaGG design in an unofficial capacity, working out of little more than a hut with an airfield next to it. The eventual product of the work was a modified LaGG-3 housing a 1,510hp ASh-82A radial engine. The prototype first flew in March of 1942, and after some persuasion by the test pilots, Stalin immediately ordered full production of the new aircraft. The first La-5's off the production line, however, ran into some workmanship problems. Many were up to 30mph slower than the prototype had been, and difficulties with the laminated wood airframe remained. Eventually these quality control issues were sorted out, though, and when it was finished the plane achieved a top speed of 375mph at an altitude of 21,000ft. The new La-5s were fitted with two 20mm guns with 200 rounds each, and they outperformed the principle German foes, the Bf-109 and FW-190, at the generally low altitudes involved in much of the Russia/Germany conflict. And all in time for the Battle of Stalingrad.
Improvements instituted over the winter of 1942 involved the installation of a fuel injected ASh-82FN engine. It was rated at 1,700hp, and would eventually be improved to 1,850hp. The more powerful engine and the use of some additional metal parts resulted in a new top speed for the newly-designated La-5FN of 403mph. Further refinements in the craft's aerodynamics would result in the pinnacle of Soviet fighter technology during the war -- the Lavochkin La-7. 9,920 La-5s were produced, including the FN and some training models.
Powerplant: 1380kW (1850hp) M-82FN (ASh-82FN) 14-cylinder radial engine
Max Speed: 647km/h (402mph) at 5,000m (16,404ft)
Ceiling: 11,000m (36,089ft)
Max Range: 765km (475 miles)
Armament: 2x 20mm ShVak nose cannons (200 rounds per gun)
8x 8.2cm (3.23in) RS-82 rockets, or
150kg of bombs.
Wing Span: 9.8m (32ft 2in)
Length: 8.67m (28ft 4in)
Height: 2.84m (9ft 3in)
Empty Weight: 2,605kg (5,743lb)
Max Weight: 3,402kg (7,500lb)
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