If any of you is searching for a HUD photo which shows a F-15 gets locked by a Su-27, I have one and I can upload it tonight.
http://s18.postimage.org/tpya2h65z/Su27_locked_on_F15.jpg
But it was not a real dog fight, since the eagle was carrying 3 fuel tanks. It was more of a joke during a scheduled formation flight. A flanker locked a eagle from the rear and the eagle tried to get rid of the tailing flanker but failed, because of the heavy payload.
JASDF used to have numerous conflicts against China's airforce. A magazine showed a China's Flanker (From google I was gathering that it's also known as J-12 because Chinese has made some modification), which was maneuvering aggresively against a JASDF eagle, but finally got owned. The translation is as follows:
I was flying calmly as usual, so I didn’t expect that when we met, he was moving offensively. I still had one fuel tank under my fuselage and won't drop it, so I set the engine to maximum thrust to turn and climb abruptly. He tried to follow, but he failed because he lost too much speed, so he descended to accelerate. I could read this from my HUD.
http://s7.postimage.org/uo8lbal49/JASDF_01.png
Ok, one fight alone does not prove much since this might be a special case. China's modification on J-12 may have made the flanker heavier, thus less maneuverable.