Summary
We propose to adopt a new airworthiness directive (AD) for certain Airbus Model A319-113, A319-114, A320-211, and A320-212 airplanes. This proposed AD was prompted by a report that the aft mount pylon bolts of the CFM56-5 engines may have been installed using the wrong torque values. This proposed AD would require identification of engines that were installed using the wrong torque values and re-torque of the four aft mount pylon bolts of those engines. We are proposing this AD to detect and correct improper torque of the aft mount pylon bolts, which, if combined with any maintenance damage, could lead to aft engine mount failure, possibly resulting in engine detachment and consequent reduced control of the airplane.