COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Bell Helicopter Textron 47 (All Variants) Series Helicopters
AD/BELL 47/62
Amdt 2
Centre Fuselage Frame Assembly 5/87
Applicability: All model 47D, 47G and 47J Series.
Requirement: Inspect the following fuselage frame assembly tubes for internal corrosion using radiographic technique, DCA/NDI/R/3A or other technique approved by the Secretary:
(a) Sections of the three main side tube LH and RH which meet at the engine basket pick-up junction, top and bottom.
(b) The centre of the lower longerons LH and RH.
(c) A section of the upper longeron LH and RH, adjacent to the engine pick-up basket.
(d) For “D” and “G” models inspect the tubes described in (a), (n) and (c) plus the first cross tube in the tail boom structure and the forward ends of the upper tail boom longerons LH & RH.
Note: The length of the tube inspected at each location should be not less than 25.4 cm (10 inches). Where a tube is found to contain corrosion, the entire length of that tube and sample lengths of adjacent tubes must be inspected to ascertain the extent of the corrosion.
Compliance: Unless already accomplished in accordance with earlier issues of this Directive, within 5 years from date of manufacture and thereafter at intervals not exceeding six years.
Background: A survey of radiographic results and defect reports has indicated that the tube corrosion problem is well under control and therefore the periodicity of the inspection may be relaxed.