AD 78-15-01

78-15-01 MCDONNELL DOUGLAS: Amendment 39-3266. Applies to Model DC-8-62, -62F, -63, and -63F airplanes, certificated in all categories.

Compliance required as indicated, unless already accomplished.

To detect cracks and prevent failure of the wing lower forward spar cap, tee doubler, and wing skin, comply with the following:

(a) Within the initial time period specified by column 2 of the compliance period table of paragraph (c), or at the time specified in AD 78-09-01, if that inspection comes due between the effective date of this AD and the time specified by paragraph (c) column 2, whichever occurs sooner, and thereafter, at intervals not to exceed 1,000 landings since the last inspection, perform x-ray and ultrasonic inspections for cracks in lower wing structure at all four pylon attach areas in accordance with the Accomplishment Instructions section of McDonnell Douglas DC-8 Service Bulletin 57-83, Revision 3, dated June 15, 1978.

(b) Within the time period specified by column 3 of the compliance period table of paragraph (c), modify the airplane in accordance with Option 1 of McDonnell Douglas DC-8 Service Bulletin 57-84, dated August 12, 1977.

(c)

(1) Airplane total landings on (2) Initial Inspection (landings) (3) Modification (in landings from effective date of this AD

initial insp. per this AD)

0-6999 Prior to 8000 total 4000 7000-9999 within 1000 4000 10,000-10,999 within 800 3000 11,000-and over within 400 3000

(d) If cracks are found in the wing spar cap and/or wing skin as a result of the inspections of paragraph (a), before further flight repair in accordance with Condition 2 of McDonnell Douglas DC-8 Service Bulletin 57-83, Revision 3, dated June 15, 1978, and inspect thereafter at intervals not to exceed 1,000 landings, per paragraph (a), until the modification per paragraph (b) is accomplished. Cracked pylon tee doublers shall be replaced before further flight if the cracks exceed the limits in McDonnell Douglas DC-8 Service Bulletin 54-58, dated May 15, 1970.

(e) Airplanes modified in accordance with Option 1 of McDonnell Douglas DC-8 Service Bulletin 57-84, dated August 12, 1977 are no longer subject to the inspection requirements of this AD.

(f) Equivalent inspections, repairs and modifications may be used when approved by the Chief, Aircraft Engineering Division, FAA Western Region.

(g) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of inspections required by this AD with prior approval of the Chief, Aircraft Engineering Division, to operate airplanes with a cracked spar to a base for repair and/or modification as required by this AD.

(h) If the number of landings on an aircraft is not known, for the purpose of complying with this AD, subject to acceptance by the assigned FAA maintenance inspector, the number of landings may be determined by dividing the airplane's hours time in service by the operator's fleet average time from takeoff to landing for the airplane type.

This supersedes Amendment 39-3197 (43 FR 19207), AD 78-09-01.

This amendment becomes effective July 24, 1978.