The project, code-named "Tunguska", was undertaken to improve on the observed shortcomings of the ZSU-23-4 (short range and no early warning) and a counter to new ground attack aircraft in development, such as the A-10 Thunderbolt II, which was designed to be highly resistant to 23 mm cannons. Studies were conducted and demonstrated that a 30 mm cannon would require from a third to a half of the number of shells that the 23 mm cannon of the ZSU-23-4 would need to destroy a given target, and that firing at a MiG-17 (or similarly at, in case of war, NATO's Hawker Hunter or Fiat G.91) flying at 300 m/s, with an identical mass of 30 mm projectiles would result in a kill probability 1.5 times greater than with 23 mm projectiles. An increase in the maximum engagement altitude from 2,000 to 4,000 m and increased effectiveness when engaging lightly armoured ground targets were also cited.