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. Despite its wooden construction, it was both overweight and underpowered. At one point in the war, on average 12 LaGG-3s were being completed daily and 6,528 had been built in total when Factory 31 in Tbilisi switched production to the Yak-3 in 1944. The prototype of the LaGG-3 was called the I-301 and was designed by Semyon A. Lavochkin, Vladimir P. Gorbunov and Mikhail I. Gudkov. The prototype was later renamed the LaGG-1 and production aircraft were called the LaGG-3. The prototype was designed and produced by the GAZ-301 factory in Khimki to the North West of Moscow. The design was approved for production in January of 1940 and in the prototype's name the I- prefix stood for istrebitel "destroyer" and the number signified the design bureau responsible (which in this case was the GAZ-301 factory). The I-301 was a single-seat, low-wing monoplane, with a semi-monocoque fuselage, and skinned with birch veneer and plywood. The I-301 airframe was partially made of "delta wood": a material composed of very thin (0.35–0.55 mm) layers of birch or pine wood veneer, and a phenol-formaldehyde resin known as VIAM-B-3, which together were baked at high temperatures and pressures. Delta wood was used for critical parts of the airframe. This novel construction material had tensile strength comparable to that of non-hardened aluminum alloys and only 30% lower than that of precipitation hardened D-1A grade duralumin. It was also incombustible and completely invulnerable to rot, with service life measured in decades in adverse conditions. During production of the prototype, it was discovered that the adhesive used in delta wood caused skin irritation and safety procedures needed to be devised for workers. 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 from two spars. The fuselage was of similar construction to the MiG-1. For details of armament, operational history and variants, click here.
