Semyon A Lavochkin, together with V P Gorbunov and M I Gudkov, established a new design bureau in September 1938, and began work on a single-seat tactical fighter. Initially designated I-22, the fighter was novel in that plastic-impregnated wood known as delta drevesina was used extensively in its construction, with stressed bakelite plywood skinning. Power was provided by a 1,100hp Klimov M-105P engine with a 23mm VYa-23V cannon mounted between the cylinder banks, the remaining armament comprising two 12.7mm UB machine guns in the forward upper decking.
Work began simultaneously on seven prototypes, and a pre-series of 100 fighters was laid down. The first prototype was flown on 30 March 1940, the designation having meanwhile been changed to LaGG-1.
It demonstrated inadequate range, ceiling and manoeuvrability, and potentially dangerous handling characteristics. Time did not permit fundamental redesign of the fighter, and the Lavochkin team therefore initiated a programme aimed at alleviating the more serious of the fighter's defects. Improvements were progressively introduced, while the design was subjected to a thoroughgoing weight analysis. The large calibre machine guns were replaced by 7.62mm ShKAS guns, and the 23mm cannon gave place to one of 20mm. Various remedies for the handling shortcomings were applied, and the first LaGG-1 prototype to introduce these changes was referred to as the I-301 (from the numerical designation of the factory - GAZ-301). This also featured redesigned outer wing panels incorporating additional fuel tanks. The I-301 entered flight test on 14 June 1940, the modified aircraft being assigned the designation LaGG-3 and most pre-series examples of the LaGG-1 being completed to the later standard.
Engine: 1 x 1,100hp Klimov M-105P
Max take-off weight: 3380 kg / 7452 lb
Empty weight: 2968 kg / 6543 lb
Wingspan: 9.80 m / 32 ft 2 in
Length: 8.81 m / 28 ft 11 in
Height: 4.40 m / 14 ft 5 in
Wing area: 17.50 sq.m / 188.37 sq ft
Max. speed: 600 km/h / 373 mph
Range: 660 km / 410 miles