AD/EC 225/4 Amdt 1 Main Rotor Hub Dome Fairing Attachment Screws (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/EC 225/4 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.

Eurocopter EC 225 Series Helicopters

AD/EC 225/4 Amdt 1 Main Rotor Hub Dome Fairing
Attachment Screws 4/2009

Applicability:

Model EC 225 LP helicopters, all serial numbers, except those that have been modified during production with MOD 0743718 or in-service with Eurocopter EC225 Service Bulletin (SB) No. 62-007 original issue, or later EASA approved revision.

Requirement:

1.    Check that there is no crack in the dome fairing support and readjust the tightening torque of the screws which secure the dome fairing support to the dome fairing, in accordance with instructions specified in paragraph 2.B.2 of EUROCOPTER EC 225 Alert Service Bulletin (ASB) No. 05A005 Revision 1, or later EASA approved revision.

2.    Readjust the tightening torque of the dome fairing support attachment screws on the dome fairing, in accordance with the instructions specified in paragraph 2.B.3 of ASB No. 05A005 Revision 1, or later EASA approved revision.

Checks and corrective actions accomplished before the effective date of this Directive in accordance with ASB No.05A005 at original issue are acceptable compliance with the initial requirements of Requirements 1 and 2 of this Directive.  After the effective date of this Directive, repetitive checks and corrective actions as required by Requirement 2 of this Directive must be accomplished in accordance with ASB
No. 05A005 at Revision 1.

If, during any check required by this Directive, a crack is found in the dome fairing support at the dome fairing attachment points, before further flight, remove and replace the dome fairing support and the associated coning stop support assembly in accordance with the instructions of SB No. 62-007 original issue, or later EASA approved revision.

Replacement of parts in accordance with the instructions of SB No. 62-007 original issue, or later EASA approved revision, constitutes terminating action for the repetitive checks required by Requirement 2 of this Directive.

Note:  EASA AD 2009-0023 refers.

Compliance:

1.    Unless the initial check is already accomplished, before further flight after
9 April 2009.

2.    At intervals not to exceed 165 flight hours; until compliance with SB No. 62-007 original issue, or later EASA approved revision.

This Amendment becomes effective on 9 April 2009.

Background:

This Emergency Airworthiness Directive was issued following the discovery of two cracks in the dome fairing attachment on the dome fairing support.  These fatigue cracks were due to the loss of tightening torque of the screws which secure this assembly.  These cracks, in time, can lead to the loss of the dome fairing in flight.

Amendment 1 is issued in response to a new EASA AD, which introduces the latest revision of the Requirement document, and modification 0743718 (and associated SB No. 62-007) which constitutes terminating action for the repetitive checks required by this Directive.

David Villiers
Delegate of the Civil Aviation Safety Authority

25 February 2009