Indeed J-10 is suffering from a relatively higher crash loss rate compared to most of the other military aircrafts in China, ppl are complaining about this issue recently. The single-engine design, together with the poorly engineered modification of AL-31FN together caused this problem. AL-31 was meant for twin-engine jets, their analog control box was first designed to be on the upper frontal portion of the engine housing, in order to be fitted into J-10, it had to be modified that the control box was moved to the lower portion (AL-31FN version). Apparently this has caused reliability issue that the lube oil get unpredictably overheated under certain conditions, this has been the cause to virtually all J-10 crashes due to "Mechanical Failure".
It is not feasible to ask Russians to redesign the whole stuff, so the only cure to this problem is WS-10 turbofan, which to much of our delight, is being tested and fitted to newer J-10 variants.
How do you come to the conclusion J-10 has a higher crash rate compare to most other military aircraft in China? And the fact Russian AL-31FN engine has long history problem of poor quality. Both China and India have long complain of AL-31 engine issue. It can never be design issue. All the time is the engine stop working.
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