Ad/Dhc-1/15 - Tail Landing Gear and Lower Surface of Tailplane - Inspection and Modification - Cancelled (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/DHC-1/15.

De Havilland DHC-1 (Chipmunk) Series Aeroplanes

AD/DHC-1/15 Tail Landing Gear and Lower Surface of Tailplane - Inspection and Modification 10/2008

Requirement:

CANCELLED.

This AD is cancelled on 25 September 2008.

Background:

This unique Australian AD superseded AD/DHC-1/10 and was raised in 1962 following an accident where the tail landing gear upper shock absorber attachment bolt failed allowing the tail gear to collapse.  Partially sheared bolts were frequently found after heavy landings.  Most operators were aware of the possibility of distortion of the tailplane lower skin and possible fouling of the elevator control rod during the early stages of take-off should a damaged bolt or fitting fail.

The purpose of the AD was to introduce and formalise a procedure of regular inspection, and inspection after heavy landing, which was already well known to experienced operators of this aircraft type at that time.

Compliance was daily and after a heavy landing, and at intervals not exceeding 100 hours TIS and after a heavy landing.

Given the length of time this AD has been promulgated, that no defects have been recorded on the mandatory defect reporting system, and that the type of damage that could occur following a heavy landing is well known to operators, this AD is no longer required.

David Villiers
Delegate of the Civil Aviation Safety Authority

15 August 2008