Other easily visible differences to its predecessor were the addition of a third wing fence on each wing, the addition of a ventral fin and a longer and less tapered rear fuselage that added about one meter in length. The MiG-17 shared the same Klimov VK-1 engine, and much of the rest of its construction such as the forward fuselage, landing gear and gun installation was carried over. The first prototype, designated I-330 "SI" by the construction bureau, was flown on the 14 January 1950, piloted by Ivan Ivashchenko.