AD/Convair/13 Main Landing Gear Trunnion Fittings (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.

Kelowna Flightcraft (General Dynamics/Convair) Series Aeroplanes

AD/CONVAIR/13 Main Landing Gear Trunnion Fittings 5/2006

Applicability:

Model 340 and 440 aircraft, and all such model aircraft converted to turbopropeller power.

Requirement:

1.    Visually inspect main landing gear trunnion fittings part number 340-8510109 for crack indications in the outboard fitting face and inboard boss area, primarily in the upper area of the fitting above the boss radius, by dye penetrant inspection procedures, in accordance with General Dynamics 640 (340D) Service Bulletin No. 57-4, dated 25 May 1970.

2.    If no cracks are detected, repeat the Requirement 1 inspection procedure.

3.    If cracks are detected during any Requirement 1 inspection, accomplish one of the following:

a.     If trunnion fitting cracking exceeds 2-inches or if a crack is detected in the trunnion boss face, replace the fitting before further flight.

b.    If cracking is in excess of 1-inch in length but less than 2-inches in length, either replace the fitting or stop-drill using a 0.25-inch drill and reinspect daily for crack growth until the fitting is replaced.

c.     If cracking is 1-inch in length or less, either replace the fitting or stop-drill using a 0.25-inch drill and reinspect for crack growth at intervals not to exceed 50 hours time in service.

Note 1:  Where insufficient clearance precludes the use of a 0.25-inch drill, it is permissible to use a 0.1875-inch drill.

4.    Replace stop-drilled fittings.

Any crack progressing beyond a stop-drilled hole may be stop-drilled again if the total crack length is less than 2-inches.  This fitting must be replaced if a crack progresses to 2-inches or more in length.

Note 2:  FAA AD 70-12-05 refers.

Compliance:

1.    Unless the initial inspection is already accomplished, within 50 hours time in service after 11 May 2006 unless accomplished within the last 450 hours time in service.

2.    At intervals not to exceed 500 hours time in service.

3.    Before further flight.

4.    Within 500 hours time in service from initial stop-drilling.

This Airworthiness Directive becomes effective on 11 May 2006.

Background:

The FAA requires inspections to detect cracks and prevent failure of the main landing gear trunnion fittings.

David Villiers
Delegate of the Civil Aviation Safety Authority

29 March 2006