Sunday, March 13, 2011

Lavochkin-Gorbunov-Gudkov LaGG-3

LaGG-3
A Series 35 LaGG-3 (Finnish markings).
Role fighter
Manufacturer Lavochkin-Gorbunov-Gudkov
First flight March 30, 1940
Introduced early 1941
Primary user Soviet Union
Produced 1941-1942
Number built 6,258
Variants Lavochkin La-5
Lavochkin La-7
The Lavochkin-Gorbunov-Gudkov LaGG-3 (Лавочкин-Горбунов-Гудков ЛаГГ-3) was a Soviet fighter aircraft of World War II. It was a refinement of the earlier LaGG-1, and was one of the most modern aircraft available to the Soviet Air Force at the time of Germany's invasion in 1941.

Contents

  • 1 Design and development
  • 2 Operational history
  • 3 Variants
  • 4 Operators
  • 5 Specifications LaGG-3 (data for LaGG-3 series 66)

Design and development

The prototype of the LaGG-3, I-301, was designed by Semyon A. Lavochkin, Vladimir P. Gorbunov and Mikhail I. Gudkov. It was designated LaGG-3 in serial production. Its airframe was almost completely made of timber, with crucial parts processed with Bakelite lacquer. This novel wood-laminate construction was more durable than regular timber, incombustible, and didn’t rot. It was, however, much heavier and pilots joked that rather than being an acronym of the designers' names (Lavochkin, Gorbunov, and Goudkov) "LaGG" stood for lakirovanny garantirovanny grob ("(the) varnished guaranteed coffin" - лакированный гарантированный гроб). The full wooden wing (with plywood surfaces) was analogous to that of the Yak-1. The only difference was that the LaGG’s wings were built in two sections. The fuselage was the same as the MiG-3’s.[1] But the LaGG-3’s armament was considered formidable. It consisted of a large-calibre BK machine gun, which was installed between the "V" of the cylinders of the engine and two synchronized ShKAS machine guns. Consequently the weight of fire was 2.65 kg/s, making the LaGG superior to all serial Soviet fighters, as well as the 1941 version of the Messerschmitt Bf 109.[2]

Operational history

The LaGG-3 rapidly replaced the LaGG-1 although the new fighter was too heavy for its engine. In fact, Lavochkin, Gorbunov and Gudkov had originally designed their prototype for the powerful Klimov M-106 engine. But it proved to be unreliable. So they were obliged to install the relatively weak Klimov M-105P. As a result, the LaGG was slow; its top speed was just 474 km/h, while its rate of climb at ground level was as slow as 8.5 meters/second. The LaGG-3 proved to be somewhat hard to control as it reacted sluggishly to stick forces. In particular, it was difficult to pull out of a dive, and if the joystick was pulled too hard, it tended to fall into a spin. As a consequence, sharp turns were difficult to perform.[2] A more powerful engine was installed, but the improvement was little so, the only solution was to lighten the airframe. The LaGG team re-examined the design and pared down the structure as much as possible. Fixed slats were added to the wings to improve climb and manoeuvrability and further weight was saved by installing lighter armament. But the improvement was slight and without an alternative powerplant thus, when the LaGG-3 was first committed to combat in July 1941, it was completely outclassed by the Messerschmitt Bf 109.[2]
Later in 1941, the LaGG-3 appeared with new armament options, an internally balanced rudder, retractable ski landing gear for the winter, retractable tailwheel and wing pipes for drop tanks.[3] The result was still not good enough. Even with the lighter airframe and supercharged engine, the LaGG-3 was underpowered.
The LaGG-3 proved immensely unpopular with pilots. Some aircraft supplied to the front line were up to 40 km/h (25 mph) slower than they should have been and some were not airworthy. In combat, the LaGG-3's main advantage was its strong airframe. Although the laminated wood did not burn it shattered when hit by high explosive rounds.
The LaGG-3 was improved during production, resulting in 66 minor variants in the 6,258 that were built. Experiments with fitting a Shvetsov M-82 radial engine to the LaGG-3 airframe finally solved the power problem, and led to the superb Lavochkin La-5[4]
Soviet pilots generally disliked this aircraft. Pilot Viktor M. Sinaisky recalled: "It was an unpleasant client! Preparing the LaGG-3 for flight demanded more time in comparison with other planes. All cylinders were supposed to be synchronized: God forbid you from shifting the gas distribution! We were strictly forbidden to touch the engine! But there were constant problems with water-cooled engines in winter: especially as there was no antifreeze liquid. You couldn't keep the engine running all night long, so you had to pour hot water into the cooling system in the morning. Furthermore, pilots didn't like flying the LaGG-3 - a heavy beast with a weak M-105 engine - but they got used to it. Even so, we had higher losses on LaGG-3 than on I-16s."[5]
Even with its limitations, some Soviet pilots managed to reach the status of ace flying the LaGG-3. G.I. Grigor'yev, from 178.IAP, was credited of at least 11 air victories plus two shared. But pictures of his LaGG-3 "Yellow 6", in November-December 1941, show 15 "stars", so his score was probably higher.[6]
.[6]

Variants

  • Gorbunov 105 - A lightened LaGG-3 with improved performance and improved rear vision with cut down rear decking, overtaken by newer aircraft such as the La-5.
  • LaGG-3IT - LaGG-3 66 series with a NS-37 Cannon

Operators

 Finland
 Germany
  • Luftwaffe operated captured examples for tests. One captured example was used for a propaganda movie in 1943.[8]
 Japan
 Soviet Union

Specifications LaGG-3 (data for LaGG-3 series 66)

Data from Jane’s Fighting Aircraft of World War II[10]
General characteristics
  • Crew: One
  • Length: 8.81 m (28 ft 11 in)
  • Wingspan: 9.80 m (32 ft 1.75 in)
  • Height: 2.54 m (8 ft 4 in)
  • Wing area: 17.4 m² (188 ft²)
  • Empty weight: 2,205 kg (4,851 lb)
  • Loaded weight: 2,620 kg (5,764 lb)
  • Max takeoff weight: 3,190 kg (7,018 lb)
  • Powerplant:Klimov M-105PF liquid-cooled V-12, 924 kW (1,260 hp)
Performance
Armament

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