60-25-01 CURTISS-WRIGHT: Amdt. 230 Part 507 Federal Register December 6, 1960. Applies to all C-46A, D. E. F. and R; C-46/CW20T; Super C-46/CW20T; Super 46; and Super 46C aircraft.
Compliance required as indicated.
Due to fatigue failures found in the outer wing panel attachment bolts, the following must be accomplished:
(a) On aircraft having outer wing panel attachment bolts with 10,000 or more hours' time in service that have accumulated more than 5,000 hours' flight time since the last inspection of such bolts, the outer wing panel attachment bolts must be inspected for cracks, elongation and corrosion prior to the next flight except aircraft may be ferried without a special flight permit one time only, with occupancy limited to the required flight crew, to a base where personnel and facilities for required work are available.
(b) On aircraft having outer wing panel attachment bolts with 10,000 or more hours' time in service that have accumulated less than 5,000 hours' flight time since the last inspection of such bolts, the outer wing panel attachment bolts must be reinspected for cracks, elongation and corrosion within the next 25 hours of flight time.
(c) Outer wing panel attachment bolts found, during the inspections under (a) or (b), to be cracked, elongated or corroded must be replaced with new bolts prior to further flight.
(d) Outer wing panel attachment bolts which are not found, during the inspections under (a) or (b), to have cracks, elongation or corrosion, may be reused for a total time not to exceed 500 hours' flight time after such inspection at which time all such bolts must be replaced with new bolts.
(e) After compliance with the requirements of paragraph (c) and/or (d) all outer wing panel attachment bolts must be replaced at intervals of 10,000 hours' time in service.
(f) New bolts, P/N's SS 157-7-21 or MS 20007-21 or NAS 147-35 (31 per wing) and P/N's SS 157-6-20 or MS 20006-20 or NAS 146-33 (88 per wing) or FAA approved equivalents are acceptable replacements.
This airworthiness directive sent by telegram to all known operators of Curtiss-Wright C- 46 Series aircraft by individual telegrams dated October 25, 1960, and amendment telegram dated October 26, 1960. Effective on date of publication in the Federal Register to all persons not receiving telegrams of October 25 and 26, 1960.