AD/Bell 222/26 Amdt 1 Main Rotor Grips and Pitch Horns (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/BELL 222/26 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.

Bell Helicopter Textron Canada (BHTC) 222 Series Helicopters

AD/BELL 222/26 Amdt 1 Main Rotor Grips and Pitch Horns 8/2005 DM

Applicability:

BHTC Model 222, 222B, 222U, and 230 helicopters; equipped with Main Rotor Hub Assemblies Part Number 222-011-101- all dash numbers, and Part Number 222-012-101- all dash numbers, with 1,250 or more flight hours time in service.

Requirement:

1.    Check the main rotor grips and pitch horns for cracking in accordance with the Part I instruction contained in BHTC Alert Service Bulletin 222-02-93 Revision A, 222U-02-64 Revision A, or 230-02-26 Revision A, as applicable; or later Transport Canada approved revision(s).

2.    Perform a visual inspection of the main rotor grips and pitch horns in accordance with the Part II instruction contained in BHTC Alert Service Bulletin 222-02-93 Revision A, 222U-02-64 Revision A, or 230-02-26 Revision A, as applicable; or later Transport Canada approved revision(s).

3.    Perform the new 2,500 hour inspection on the main rotor hub assembly as per Chapter 5, Revision 3, or later Transport Canada approved revision of the applicable maintenance manual

If a crack is found, replace the failed part before further flight.  Report finding to Bell Helicopter Textron - Product Support Engineering.

Note:  Transport Canada AD CF-2002-23R1 refers.

Compliance:

1.    Unless the initial inspection has been accomplished, before further flight after 29  June 2005, and thereafter at daily intervals unless Requirement Part 2 or 3 has been conducted on that day.

2.    Within the next 7 days or 10 hours time in service after 29 June 2005, whichever occurs first.  Thereafter at intervals not to exceed 25 hours time in service.

3.    For rotor heads with less than 2,500 flight hours, upon accumulating 2,500 flight hours.

       For rotor heads that have accumulated more than 2,500 flight hours as at the effective date of this Directive, and not previously inspected per the new 2,500 flight hour inspection; within 6 months or 300 flight hours after 29 June 2005.

       Inspect thereafter at intervals not to exceed 2,500 flight hours.

This Directive shall be entered on the Maintenance Release as maintenance required. The Requirement 1 Daily Check may be performed and certified by the Pilot in Command who has been trained to do the inspection by an appropriately qualified person.  In this case, a copy of this Directive and applicable Requirement document is to be carried in the aircraft.

This Amendment becomes effective on 29 June 2005.

Background:

Transport Canada was advised of three occurrences of cracked main rotor grips and three occurrences of cracked pitch horns.  These cracks were found during routine inspection of the rotor head.  There was an immediate need for repeated daily checks and 25 hour visual inspections of the affected parts for cracking while the investigation into the cause of the premature failures and appropriate terminating action was being determined.

Amendment 1 is issued to reflect the requirements of revisions of the related Transport Canada AD and Requirement documents, which introduce a newly developed enhanced inspection on the main rotor hub assembly.

David Villiers
Delegate of the Civil Aviation Safety Authority

23 June 2005