AD/Bell 47/101 Scissors Assembly and Weld Assembly Scissors Bracket (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.

Bell Helicopter Textron 47 (All Variants) Series Helicopters

AD/BELL 47/101 Scissors Assembly and Weld
Assembly Scissors Bracket 13/2005 DM

Applicability:

Bell Model 47D1, 47G, 47G-2, 47G-2A, 47G-2A-1, 47G-3, 47G-3B, 47G-3B-1, 47G-3B-2, 47G-3B-2A, 47G-4, 47G-4A, 47G-5, and 47G-5A helicopters; and, Coastal Helicopters Inc. OH-13H (Tomcat Mark 5A, 6B, or 6C) helicopters:

Equipped with scissors assembly part numbers 74-150-949-9, or 74-150-949-5, 74-150-249-5M; or,

Equipped with weld assembly scissors bracket part number 74-150-117-13M.

All Model 47 series helicopters not listed above that are equipped with the affected parts that were produced under PMA No. PQ808SW or installed under STC No. SH2772SW;

Requirement:

Determine and record on the service record or equivalent record, the total hours time in service of each affected part.

If the hours time in service cannot be determined, or if the total hours time in service is 5,000 or more hours, before further flight, replace the affected part with a new part or a serviceable part with known hours time in service.

Note 1:  This Directive establishes a life limit of 5,000 hours time in service for each affected PMA-produced scissors assembly and each affected PMA-produced weld assembly scissors bracket.

Note 2:  Texas Helicopter Co., Inc. Service Bulletin No. SB 003 dated 1 December 2002, refers.

Note 3:  FAA AD 2005-21-04 Amdt 39-14342 refers.

Compliance:

Within 60 days after 21 November 2005.

Thereafter, replace each affected part before it accumulates 5,000 hours time in service.

This Airworthiness Directive becomes effective on 9 November 2005.

Background: The FAA has determined the need to establish a life limit on scissors assemblies and weld assembly scissors brackets produced under PMA No. PQ808SW or installed under Supplemental Type Certificate No. SH2772SW.  The actions specified by this Directive are intended to establish a life limit to prevent using a scissors assembly or weld assembly scissors bracket past it’s life limit, which could result in failure of the part and subsequent loss of control of the helicopter.

David Villiers
Delegate of the Civil Aviation Safety Authority

3 November 2005