sceptical of the need for the changes. After brief factory trials, the aircraft turned out to be better than the single-seat Yak-1, thanks to the modifications already applied to the UTI as well as a revised undercarriage with bigger tires and wheels, more efficient brakes and revised elevators, among other changes. Yakovlev submitted the Yak-7 to the authorities who approved it immediately. The firing tests at the scientific trials Polygon for aircraft armament (NIPAV) were a success and the armament was found to have no effect on the flight characteristics or the general performances of the new fighter. The aircraft's stability as a firing platform was judged far better than that of the Yak-1, the Lavochkin-Gorbunov-Gudkov LaGG-3 and Mikoyan-Gurevich MiG-3. The GKO and the NKAP issued decrees in August 1941 for the Yak-7 to be produced by Factories N° 301 and N° 153, but Factory N° 301 had to be evacuated to Novosibirsk where it merged with N° 153. So, just 62 aircraft were produced in 1941: 51 in September–October by Factory N° 301 and 11 by N° 153 in December. Test pilot A.N. Lazarev noted the good flight characteristics, how easy it was to get out of a spin, and how well it behaved when diving: characteristics that he considered safer than those of the Yak-1. But the Yak-7 showed some defects: the M-105P engine piping, the landing gear locking system, the tires and the tail wheel were identified. The Yak-7 was introduced into the production line and the first batch of 60 reached operational squadrons by the end of 1941. Another important variant was the Yak-7/M-105PA. On this model, the two ShKAS on the cowling had been replaced by two UBS machine guns with 400 rounds (260 for the left and 160 for the right). It was powered by an M-105PA engine with an axial ShVAK cannon with 120 rounds. Oil and glycol radiators had been widened and refined and slightly tilted downward. The insulation of the airframe was improved, the tail wheel was totally retractable; joints and skin were more carefully made; the panels on the engine cowling fitted better; the propeller reduction gear worked better; an electro-pneumatic reloading system was installed; the canopy frame was reinforced. The Yak-7B made 27 tests flights in January and February 1942. The reports noted that while the aircraft "was not inferior to the LaGG-3 and MiG-3 and to foreign fighters