AD/Bell 47/102 Main Rotor Blades Box Beam Clips (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 47/102 Main Rotor Blades Box Beam Clips 8/2009 DM

Applicability:

Model 47, 47B, 47B3, 47D, 47D1, 47E, 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, 47G-5A,
47H-1, 47J, 47J-2, 47J-2A and 47K helicopters, with a main rotor blade part number and serial number listed below, installed:

Blade Part Number                  Blade Serial Number

047-110-250-021                   A-303, A-304, A-312 or A-316

047-110-250-023                   A-298, A-301 or A-305

Requirement:

Visually inspect the entire length of each main rotor blade from the main rotor blade tip to the root in accordance with Part II of the Accomplishment Instructions, paragraphs 1. through 8. of Bell Helicopter Textron Inc. Alert Service Bulletin (ASB) No. 47-08-25, 26 May 2008, or later FAA approved revision; and referring to the depictions in Figures 1 and 2 of ASB No. 47-08-25, and Figure 1 of this Directive for correct installation.

Figure 1 - Correct Installation of Clip for Box Beam

If a main rotor blade is found with an incorrectly installed clip, before further flight, replace that unserviceable main rotor blade with a serviceable main rotor blade that has a clip that is installed correctly.

Special flight permits may be issued to operate the helicopter to a location where the requirements of this Directive can be accomplished, provided the one-time ferry flight does not exceed 5 hours time in service.

Note 1:  Figure 3 of the Requirement document depicts a clip installed incorrectly.

Note 2:  FAA AD 2009-12-01 Amdt 39-15924 refers.

Compliance:

Within 10 hours time in service after 29 June 2009, unless already accomplished.

This Airworthiness Directive becomes effective on 29 June 2009.

Background:

The FAA received a report of a main rotor blade with an incorrectly installed clip.  The actions required by this Directive are intended to prevent a main rotor blade spar crack as a result of an incorrectly installed clip, loss of a main rotor blade, and subsequent loss of control of the helicopter.

David Villiers
Delegate of the Civil Aviation Safety Authority

18 June 2009