HIALS:
Some interesting points there.
However, two questions remain:
1) Does anyone really know CAAC's true air safety record. For a considerable time (even beyond the "Great Leap Backwards" era) it was widely accepted that many tragedies went unreported - particularly those that did not involve any foreign casualties.
2) Which CAAC unit did the aircraft belong to that was said to have crashed with Lin Biao on board?