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/A109/8 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.

Agusta A109 Series Helicopters


AD/A109/8 Amdt 2

Tail Rotor Blades

6/2006
 
Applicability:
All Agusta A109A and A109AII helicopters equipped with tail rotor blades part number 109-0132-02-11, -15, and -121, which have accumulated 400 or more flight hours. Note:  Part number 109-0132-02-125 tail rotor blade is not affected by the requirements of this Directive.
Requirement:
Action in accordance with Agusta Technical Bulletin (TB) 109-110 Revision A, dated 12 December 2005. Note:  ENAC AD 2006-001 refers.
Compliance:
Part I of the Requirement document: Before further flight after 4 November 1999, unless already accomplished in accordance with TB 109-5. Part II of the Requirement document: At each daily inspection. Part III of the Requirement document: At each 100 hour inspection period. The compliance times remain unchanged by this issue of the Directive. The visual inspection required by Part II of the Requirement document may be performed by the pilot in command, in which case certification is to be made by entering AD/A109/8 Amdt 2 against the daily inspection certification of the maintenance release.  A copy of this Airworthiness Directive is to be kept in the aircraft.
 
This Amendment becomes effective on 8 June 2006.
Background:
The manufacturer received a report of a tail rotor blade failure which resulted in the loss of the tail rotor and 90 degree gearbox assembly. Amendment 1 was prompted by another incident of tail rotor and gearbox loss following failure of a tail rotor blade.  The manufacturer is currently developing an improved tail rotor blade which will alleviate the on-going repetitive inspections.
 
 
Amendment 2 is issued in response to a new ENAC AD, which limits tail rotor blade applicability to certain dash numbers and introduces a new improved tail rotor blade that is not affected by the requirements this Directive.
Richard Castles
Delegate of the Civil Aviation Safety Authority 20 April 2006