COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
DHC-6 (Twin Otter) Series Aeroplanes
AD/DHC-6/45
Amdt 1
Fuselage Side Frames Stns 218.125 and 219.525 4/92
Applicability: Model DHC-6 Series with serial numbers 1 through 411 inclusive. Requirement: 1. Action in accordance with de Havilland SB 6/371.
2. Incorporate de Havilland modifications 6/1461 (or 6/1553) and 6/1462.
Note: Transport Canada AD CF-78-17 R1 refers.
Compliance: 1. At intervals as specified in the requirement document, until modified in accordance with Requirement 2.
2. Prior to 1 January 1996.
The compliance of the previous issue of this Directive was as per Requirement Document.
This amendment is effective from 2 April 1992.
Background: Inter-rivet cracking of the fuselage side frame skin flanges at Stations 218.125 and
219.525 has occurred on a number of aircraft in service. Cracks are initiated by stress induced by riveting; side frames of material with improved stress corrosion resistance have been introduced by the manufacturer.
Amendment 1 is issued to align this Directive with a revision of the relevant Country of Origin AD which requires terminating action in lieu of on going repetitive inspections.