Airworthiness Directive · Amendment 39-17710 · CFM International S.A. Turbofan Engines
CFM International S.A. Turbofan Engines
Superseded. A later AD replaced this one: AD 2022-02-03. Comply with the one in force.
This AD applies to CFM International S.A. CFM56-3 series and CFM56-7B series turbofan engines equipped with the following accessory gearbox (AGB) part numbers (P/Ns):
(1) For CFM56-3 engines: 335-300-103-0, 335-300-105-0, 335-300-106-0, 335-300-107-0, 335-300-108-0, 335-300-109-0, or 335-300-110-0.
(2) For CFM56-7B engines (except CFM56-7B27A, CFM56-7B27A/3, and CFM56-7B27AE engines): 340-046-503-0, 340-046-504-0, or 340-046-505-0.
(3) For CFM56-7B27A, CFM56-7B27A/3, and CFM56-7B27AE engines: 340-188-601-0 or 340-188-603-0.
We are adopting a new airworthiness directive (AD) for all CFM International (CFM) S.A. CFM56-3 and CFM56-7B series turbofan engines with certain accessory gearboxes (AGBs) not equipped with a handcranking pad "oil dynamic seal" assembly. This AD was prompted by 42 events of total loss of engine oil from CFM56 series turbofan engines while in flight. This AD requires an independent inspection to verify re-installation of the handcranking pad cover after removal of the pad cover for maintenance until installation of a handcranking pad oil dynamic seal assembly. We are issuing this AD to prevent loss of engine oil while in flight, which could result in engine failure, loss of thrust control, and damage to the airplane.
Unless already done, do the actions in paragraphs (f) or (g) of this AD.
(1) Perform an Independent Inspection to verify re-installation of the AGB handcranking pad cover after any maintenance that involves the removal and re-installation of the AGB handcranking cover, or
(2) Insert an Independent Inspection as a required inspection item in the approved continuous airworthiness maintenance program for the aircraft.
As an optional terminating action to the inspection requirement of paragraph (f) of this AD, install an AGB that is not listed in paragraph (c) of this AD that incorporates the oil dynamic seal assembly.
For the purpose of this AD, an Independent Inspection means a second inspection by a qualified individual who was not involved in the original re-installation of the AGB handcranking pad cover following maintenance to confirm that the cover is installed correctly.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
