Commonwealth legislation

AD/DHC-6/71 - Fuselage Station FS 239 Frame

RepealedCTH

This Act has been repealed and is no longer in force. It is retained for historical reference.

Jurisdiction

Commonwealth

Collection

legislative instrument

Plain English Summary

3/10 complexity

If you own or operate a DHC-6 Twin Otter, you must inspect the fuselage frame at Fuselage Station 239 using the procedures in de Havilland Service Bulletin 6/521 within 1,200 flight hours or by October 1996, whichever comes first.

Small cracks within tolerance require repeated inspections per the maintenance manual; cracks beyond tolerance mean grounding and repair before further flight. This follows discovery of cracks on two aircraft and addresses a potential structural safety risk.

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Current sections

Direct links to the current provisions in AD/DHC-6/71 - Fuselage Station FS 239 Frame.

AD/DHC-6/71 - Fuselage Station FS 239 Frame

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-6/71 Fuselage Station FS 239 Frame 11/95

Applicability: All DHC-6 aircraft.

Requirement: Inspect the fuselage frames for cracks by visual methods in accordance with the Accomplishment Instructions described in de Havilland Service Bulletin 6/521.

Note: Transport Canada AD CF-95-12 refers.

Compliance: Within 1200 hours time in service after 12 October 1995 or before 12 October 1996, whichever occurs first.

(a) If crack(s) are found which are within the tolerances specified in paragraph 5, Accomplishment Instructions of SB 6/521, perform repetitive inspections in accordance with de Havilland Inspection Requirement Manual, PSM 1-6-7 Temporary Revision 77, or as detailed in PSM 1-6-7 normal revision No.8, when issued.

(b) If crack(s) are found which exceed the tolerances specified in paragraph 5, Accomplishment Instructions of SB 6/521, repair or replace the subject part area before further flight.

Background: There have been two reported instances of cracking on the skin flange of the machined fuselage frame at fuselage station FS 239.

Source text

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

1 AD/DHC-6/71 - Fuselage Station FS 239 Frame