Commonwealth legislation

AD/DHC-6/33 Amdt 4 - Elevator Root and Nose Ribs

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Commonwealth

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legislative instrument

Plain English Summary

3/10 complexity

Requires operators of DHC‑6 (Twin Otter) aeroplanes to inspect the elevator root rib for cracking per de Havilland Service Bulletin 6/399 Rev E, to repeat inspections every 600 flight hours until modification 6/1769 is fitted, and to incorporate modification 6/1769 by 1 January 1996 or 15,000 airframe hours, whichever is later (Requirement; Compliance). Issued because cracking has occurred; owners/operators pay inspection and modification costs and approved maintenance organisations carry out the work.

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Direct links to the current provisions in AD/DHC-6/33 Amdt 4 - Elevator Root and Nose Ribs.

AD/DHC-6/33 Amdt 4 - Elevator Root and Nose Ribs

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY

SCHEDULE OF AIRWORTHINESS DIRECTIVES

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DHC-6 (Twin Otter) Series Aeroplanes

AD/DHC-6/33

Amdt 4

Elevator Root and Nose Ribs 4/92

Applicability: Model DHC-6 series.

Requirement: 1. Inspect the elevator root rib for cracks in accordance with de Havilland Service Bulletin 6/399 Revision E.

If cracking is present, incorporate de Havilland modification 6/1769 before further flight.

Incorporate de Havilland modification 6/1769.

Note: Transport Canada AD CF-82-21 R1 refers.

Compliance: 1. At intervals not to exceed 600 hours time in service, until modification 6/1769 is incorporated.

Prior to 1 January 1996 or 15 000 hours airframe time in service, whichever occurs later.

The compliance of the previous issue of this Directive was:

Unless already accomplished, inspect within 200 hours time in service after 31 October 1983, with repeat inspections at intervals not exceeding 600 hours time in service until modification 6/1769 is incorporated.

This Amendment is effective from 2 April 1992.

Background: Cracking has occurred in the elevator root rib. Amendment 4 is issued to align this Directive with a revision of the relevant Country of Origin AD which requires terminating action in lieu of ongoing repetitive inspections.

Source text

Sourced from the Federal Register of Legislation (legislation.gov.au), CC BY 4.0.

1 AD/DHC-6/33 Amdt 4 - Elevator Root and Nose Ribs