AD/At 600/7 Horizontal Stabiliser Brace Tube Assembly (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.

Airtractor 600 Series Aeroplanes

AD/AT 600/7 Horizontal Stabiliser Brace Tube Assembly 7/2007

Applicability:

Model AT-602 aircraft, with serial numbers up to and including 602-0695, fitted with a part number 30012-7 horizontal stabiliser brace tube assembly.

Requirement:

1.    In accordance with Snow Engineering Co. Service Letter No. 235, dated
25 August 2004, revised 24 October 2006, or later FAA approved revision, accomplish the following:

a.     Install access holes for visual inspection of the part number 30012-7 horizontal stabiliser brace tube assembly (tube assembly).

b.    Conduct a detailed visual inspection for cracks in the part number 30012-7 tube assembly.

2.    Replace the part number 30012-7 tube assembly with a new design part number 30766-1 tube assembly in accordance with Snow Engineering Co. Service Letter No. 129A, dated 7 August 2004, revised 15 November 2005; Service Letter
No. 235, dated 25 August 2004, revised 24 October 2006; and Drill Template -602, Drawing No. SL129-602, dated 2 August 2004.

3.    A part number 30012-7 tube assembly shall not be installed on any aircraft.

Note 1:  Replacement of the part number 30012-7 tube assembly with a new design part number 30766-1 tube assembly is terminating action for the repetitive inspection requirement of this Directive.

Note 2:  FAA AD 2007-10-01 Amdt 39-15042 refers.

Compliance:

1.    Upon accumulating 2,000 hours time in service or within 60 days after 5 July 2007, whichever occurs later.  Inspect thereafter at intervals not to exceed 100 hours time in service; until a part number 30766-1 tube assembly is installed.

2.    Before further flight after any Requirement 1 inspection where cracks are found.

3.    As of 5 July 2007.

This Airworthiness Directive becomes effective on 5 July 2007.

Background: The FAA received two reports of Model AT-602 aircraft with cracked horizontal stabiliser brace tube assemblies.  Undetected cracks could result in failure of the horizontal stabiliser, and could affect the ability to control pitch with consequent loss of control.

David Punshon
Delegate of the Civil Aviation Safety Authority

16 May 2007