AD/CON/84 Amdt 2 Starter Adapter Assembly (Cth)

AIRWORTHINESS DIRECTIVE

On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/CON/84 Amdt 1 and issues the following 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.

Teledyne Continental Motors Piston Engines

AD/CON/84 Amdt 2 Starter Adapter Assembly 13/2005

Applicability:

Teledyne Continental Motors (TCM) GTSIO-520 series reciprocating engines.

Note 1:  These engines are installed on, but not limited to, Twin Commander (formerly Aero Commander) model 685, Cessna model 404, 411 series, and 421 series, British Aerospace, Aircraft Group, Scottish Division model B.206 series 2 and Aeronautica Macchi, model AM-3 aeroplanes.

Requirement:

1.    For any engine that experiences rough running conditions regardless of time-in-service (TIS), perform the inspection procedures specified in Part 1 and Part 3 of TCM Mandatory Service Bulletin (MSB) No. MSB94-4F dated 5 July 2005 or later FAA approved revisions, and replace components as necessary.

An engine is considered rough-running if there is a sudden increase in the perceived vibration levels that cannot be cleared by adjustment of the engine controls; particularly the fuel mixture setting.  Information on rough running engines can be found in the aircraft manufacturer's Aeroplane Flight Manual, Pilot's Operating Handbook, or Aircraft Owners Manual.

Special flight permits are prohibited for rough-running engines described in this AD.

2.    Perform the inspection procedures specified in Part 2 of TCM MSB No.
MSB94-4F or later FAA approved revisions, and replace components as necessary.

3.    Perform the inspection procedures specified in Part 3 of TCM MSB No.
MSB94-4F or later FAA approved revisions, and replace components as necessary.

4.    Install TCM service kit, part number (P/N) EQ6642 (New) or EQ6642R (Rebuilt).  Use the service kit installation procedures specified in Part 5 of TCM MSB No. MSB94-4F or later FAA approved revisions.

Installation of the service kit does not constitute terminating action for the inspection and component replacements detailed in other requirements of this AD.

5.    If, during an inspection required by Requirement 1, 2 or 3 of this AD, you find needle bearing, P/N 537721, installed in the crankcase, replace it with bushing P/N 654472.  Use the bushing installation procedure specified in Part 4 of TCM (MSB) No. MSB94-4F or later FAA approved revisions.

Note 2:  FAA AD 2005-20-04 Amendment 39-14297 refers.

Compliance:

1.    Before further flight.

2.    At the next 100-hour or annual inspection, whichever occurs first after the effective date of this AD.  Thereafter, at each 100-hour inspection, (plus or minus 10 hours), and annual inspection.

3.    For any starter adapter with 400 hours or more TIS or unknown TIS on the effective date of this AD;  Unless previously accomplished in accordance with TCM Critical Service Bulletin (CSB) No. 94-4 Revision D, E or MSB No.94-4F or MSB94-4G, carry out within 25 hours TIS after the effective date of this AD.  Thereafter at 400-hour TIS intervals, (plus or minus 10 hours).

For any starter adapter with fewer than 400 hours TIS on the effective date of this AD;  Upon accumulation of 400 hours TIS, (plus or minus 10 hours).  Thereafter, at 400-hour TIS intervals, (plus or minus 10 hours).

4.    Unless previously accomplished in accordance with TCM CSB No. 94-4 Revision D, E or MSB No.94-4F or MSB94-4G, carry out at the next engine overhaul or starter adapter replacement after the effective date of this AD, whichever occurs first.

5.    Before reassembling components.

Note 3:  AD/CON/71 Amdt 2 required compliance with TCM CSB No. 94-4 Revision D.  Previous compliance with that AD provides credit for work already done.  Future inspections or work should be carried out in accordance with the later revision detailed in this AD.

This Amendment becomes effective on 22 December 2005.

Background:

This AD results from six service difficulty reports and one fatal accident report received related to failed starter adapter assemblies.  The actions detailed in this AD are intended to prevent failure of the starter adapter assembly and or crankshaft gear, resulting in failure of the engine and possible forced landing.

This AD supersedes AD/CON/71 Amdt 2 and AD/CON84 Amdt 1.  The manufacturer has amended the status of the service bulletin to mandatory.  This AD allows for work carried out in accordance with previous revisions of the service bulletin.

The current amendment of the AD allows compliance with TCM MSB94-4F or later FAA approved revisions.

Amendment 1 became effective on 2 November 2005.

James Coyne
Delegate of the Civil Aviation Safety Authority

10 November 2005