COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Fairchild (Swearingen) SA226 and SA227 Series Aeroplanes
AD/SWSA226/27 Wing Main Spar - Inspection for Manufacturing Defects
6/79
Applicability: Merlin III, Model SA226-T; S/N 201, 202, 203, 204, 205, 205E, 206, 207, 208, 209,
210, 211, 212, 213, 214, 216, 217, 218, 219, 220. Merlin IV, Model SA226-AT S/N
AT002, 003, 004, 006, 007, Metro, Model SA226-TC: S/N TC201, 202, 202E.
Requirement: 1. Radiographically inspect the wing main spar lower cap for double-drilled figure- of-eight holes or other defects in the W.S. 99 area in accordance with Swearingen SB 57-015. An alternative of providing access to the area and removing fasteners for visual inspection is acceptable.
2. Inspect the spar lower cap for similar defects in the WS.81 area to a technique approved by the Secretary. It may be necessary to introduce access doors in the side of the nacelle to facilitate the placement of radiographic film.
Note: All radiographic film must be forwarded to the Secretary for review of the operator’s assessment before being forwarded to the manufacturer.
3. If, in the opinion of the Secretary, defective spars are found, re-inspect for the presence of fatigue cracking until a repair scheme acceptable to the Secretary is installed.
Note: Swearingen Drawing 27K 310007, with additional cleaning- up of hole and the use of titanium fasteners where practicable, is endorsed as a suitable repair scheme for WS.99 and could be adapted for WS.81.
Compliance: For Paras. 1 and 2: Within 300 hours time in service after 30 June 1979 unless previously accomplished.
or Para. 3 - At intervals not exceeding 300 hours until repaired, unless otherwise determined by the Secretary.
Background: Manufacturing defects have been found in three Australian and one New Guinea operated Swearingen aircraft.