Abstract: On the basis of the life control methods in common use for aircraft engines and structures,a durability and damage tolerance centered approach is presented for the life control of in-service aircraft engines in consideration of the reality in China.It is pointed out that the focus of interests for the life of non-modular engines should be put on the time between overhaul (TBO) rather than on the total life,with special emphasis on the role of the concept and practical experience of damage tolerance in the analysis.The technical difficulties in assessing durability and damage tolerance are briefly considered.It is expected that this paper will facilitate the application of damage tolerance assessments to the life control of in-service engines.