The "KDA 35mm anti-aircraft gun" developed by the Swiss company Oerlikon was adopted by the Japan Ground Self-Defense Force in 1969. It is an equipment used to shoot down enemy aircraft approaching by penetrating the anti-aircraft missile defense network using a barrage of bullets. The system consists of two twin-mounted guns, a radar and fire control system called "Super Fledermaus," one optical targeting device, and three power supply vehicles, forming one set. The radar has a measuring range of 300m to 50km, with automatic tracking up to 40km. Initially, it was a representative anti-aircraft weapon of the Japan Ground Self-Defense Force with a high hit rate, but it became outdated with the advancement of aircraft speed and performance. Procurement ended in the fiscal year 1981, and the successor equipment selected was the Type 93 short-range surface-to-air missile system, not a gun. The L90 system was gradually decommissioned and completely retired in 2009.
