The BSI were not carried out in accordance with the approved procedures; HP rotor-drive covers were not refitted after the BSI, and post-inspection, ground idle engine tests were not conducted.

• 孔探检查没有按照批准的程序实施；高压转子驱动盖子孔探检查后没有盖好，工作后检查和地面慢车试车检查没有实施。