JASDF scrambling four instead of two fighters each time

The Japan Air Self-Defense Force (JASDF) has switched from scrambling two fighters each time to four aircraft, this is so that the service can better deal with aircraft coming from China.

Yusuke D. [CC BY 2.0], via Wikimedia Commons

This is the first major change in deployment of fighters during a scramble mission since such missions were flown back in 1958.