Textron Lycoming 320 and 360 series engines - Service Difficulty Advisory

AV 1998-01
17 April 1998

Crankshaft inspection

The Federal Aviation Administration (FAA) has recently issued Airworthiness Directive (AD) 98-02-08 (effective 30 March 1998) applicable to certain Textron Lycoming 320 and 360 series reciprocating engines with ratings of 160 HP or greater installed with fixed pitch propellers.

This AD requires the inspection of the crankshaft inside diameter for corrosion and cracking using visual inspection, fluorescent penetrant inspection (FPI), and magnetic particle inspection (MPI) methods as specified in Textron Lycoming Mandatory Service Bulletin (MSB) No. 505B dated 1 December 1997. The AD does not specify any certification requirements for personnel performing the FPI and MPI methods. The AD also requires reporting to the FAA all inspection results (whether or not cracks and/or corrosion are found).

The Canadian Aviation Regulations (CARs) Part V, Paragraph 571.02(3) and Schedule 1 in Subpart 71, Aircraft Maintenance Requirements, specify minimum qualifications for personnel performing nondestructive testing (including FPI and MPI methods) on Canadian aircraft. Transport Canada reminds owners/ operators and maintenance personnel that these requirements are applicable for compliance with FAA AD 98-02-08.

The inspection area of concern is the inner diameter bore (approximately two inches) and the FPI method can be performed on wing. Transport Canada recommends that owners/ operators ensure that the FPI procedure specified in the Textron Lycoming MSB be strictly adhered to. The individual performing the FPI should pay particular attention to ensure that all excess penetrant has been removed to prevent any background fluorescence from masking a crack.

For crankshafts that are found with cracks or corrosion, owners/operators and AMEs are required to submit a Service Difficulty Report to Transport Canada, Continuing Airworthiness, Ottawa, in addition to the FAA reporting requirements of the AD.

For the service bulletin crankshafts that are found to be corrosion-free, Transport Canada strongly recommends that the protective coating specified in Textron Lycoming MSB No. 530, be applied.

Compliance with this MSB is terminating action for the repetitive inspections specified in the FAA AD.

For more information, please contact the nearest Transport Canada Centre, or contact directly Mr. Ramon A. Raoux at (613) 952-4365, facsimile (613) 996-9178, or internet e-mail: raouxr@tc.gc.ca.

For Director, National Aircraft Certification

B. Goyaniuk
Acting Chief, Continuing Airworthiness