The size and weight of the aircraft gun is not small. It is a burden for the pursuit of light and flexible fighters, and the target of the aircraft gun is too large, which is not conducive to the stealth function of the aircraft. This is also an important reason why China's R&D team did not equip the Jian 20 fighter aircraft with aircraft guns.
As a fifth-generation machine, the flexibility and stealth performance of the Jian 20 fighter is really important. If the aircraft gun is installed, although it can improve the combat capability in a small amount, it greatly affects the comprehensive level. It can be said that it is sesame and lost. Watermelon, so it is not difficult to understand why the Jian 20 fighter is not equipped with aircraft guns.
Moreover, modern air combat is basically a super-horizon warfare. The Jian 20 can launch a missile before the local radar is discovered, and then quickly disengage from the battlefield with its ultra-maneuvering flight, and there is basically no close combat situation. This is like a 6-pack of the large late-type ADC against a short-legged 6-level meat. The level gap is too large, and close combat may be dangerous, but it is difficult to do so.