PLAAF Attrition

Well, that makes 4 major Su-30MKK accidents in a year. Anyone have an analysis on that?
2003/04/15. Su-30MKK, Location: Unconfirmed, Cause: birdstrike during low level high speed flight. Outcome: airframe lost, both crew lost. Confirmation. 70%+ with eye witnesses.
2003/12/26. Su-30MKK, Location: Wuhan, Cause: ground strike during low level high speed flight. Outcome: airframe lost, both crew lost. Confirmation. 80%+ with eye witnesses and possible photo.
2004/02 Su-30MKK, Location: unknown, Cause: engine comperessor blade failure, Outcome: emergency landing, engine bay damaged. Confirmation: 100%, reported in PLA daily
2004/03/16 PLANAF Su-30MKK, Location: (?), Cause: same as 04/15 or double engine failure at low altitude. Outcome: airframe lost, both crew ejected safely. Confirmation: 80%, with some trustworthy source on chinese BBS confirming that. What is going on lately?

P.S. 3/16 accident could be at around DatuoPu AFB, ChangSha