AD/LYC/115 Lycoming Crankshaft Replacement (Cth)

AIRWORTHINESS DIRECTIVE

For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.001(1) of CASR 1998.  The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

Lycoming Piston Engines

AD/LYC/115 Lycoming Crankshaft Replacement 5/2006

Applicability:

Lycoming Engines AEIO-360, IO-360, O-360, LIO-360, and LO-360 series reciprocating engines, manufactured new or rebuilt, overhauled, or that had a crankshaft installed after 1 March 1999.

Requirement:

1.    Check serial number of your engine and crankshaft. If Table 1 of Supplement
No. 1 to Lycoming Mandatory Service Bulletin (MSB) No. 566, dated
30 November 2005, lists your engine serial number (SN), use Table 2 of Supplement No. 1 to verify if your crankshaft SN is listed.

If Table 1 of Supplement No. 1 to MSB 566 does not list your engine SN, use Table 2 of Supplement No. 1 to verify if your crankshaft SN is listed, if an affected crankshaft was installed as a replacement.

2.    If Table 2 of Supplement No. 1 lists your crankshaft SN, replace the crankshaft with a crankshaft that is not listed in Table 2 of Supplement No. 1. to Lycoming MSB 566.

Note 1:  If Lycoming Engines manufactured new, rebuilt, overhauled, or replaced the crankshaft in your engine before 1 March 1999, and you haven't had the crankshaft replaced, no further action is required.

Note 2:  The engine and crankshaft SNs listed in Table 1 and Table 2 of Supplement No.1 to Lycoming MSB 566 are different from the engine and crankshaft SNs affected by Lycoming MSBs No. 552, No. 553 and No. 566; and CASA ADs AD/LYC/107 and AD/LYC/112.

3.    Do not install any crankshaft that has a SN listed in Table 2 of Supplement No. 1 to Lycoming MSB 566 into any engine.

Note 3:  FAA AD 2006-06-16 Amendment 39-14525 refers.

Compliance:

1.    Unless previously accomplished, within 50 hours time-in-service or 6 months after the effective date of this AD, whichever is earlier.

2.    Unless previously accomplished, within 50 hours time-in-service or 6 months after the effective date of this AD, whichever is earlier.

3.    After the effective date of this AD.

This Airworthiness Directive becomes effective on 11 May 2006.
Background:	This AD results from a crankshaft failure in a Lycoming LO-360-A1H6 reciprocating engine.  CASA is issuing this AD to prevent failure of the crankshaft, which could result in total engine power loss, in-flight engine failure, and possible loss of the aircraft.

James Coyne
Delegate of the Civil Aviation Safety Authority

29 March 2006