Photos of a Shenyang J-11A taken at Guangzhou Military Region suggests China has upgraded the copy of the Su-27SK with a 360° Missile Approach Warning System (MAWS).
Two protrusions housing the optical sensors can be seen on both sides of the fueslage behind the cockpit.
Another photo also suggest that the cockpit has been modified to find a new display on the right side below the HUD.
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