AD 68-22-01

68-22-01 BOEING: Amendment 39-674. Applies to all 707-300, -400, -300B, and -300C Series aircraft listed in Boeing Service Bulletin 1796 (R-3), or later FAA approved revisions.

Compliance required as indicated.

(a) Inspect for cracks in the faying surface around and emanating from the fastener holes in the trailing edge of the upper wing skin at wing stations 211 and 232, as noted in Figure 1 of Boeing Service Bulletin 1796 (Revision 3 or later FAA approved revision), in accordance with eddy current or dye penetrant inspection techniques, at the time specified in (h) or (i). If cracks are found, repair in accordance with (e), (f) or (g), as appropriate. If cracks are not found and unless already accomplished, reinstall fasteners in accordance with step "e" of Part I of Boeing Service Bulletin 1796 (Revision 3 or later FAA approved revision) or equivalent fastener installation approved by the Chief, Aircraft Engineering Division, FAA Western Region.

(b) Unless alreadyaccomplished, conduct a one time inspection at Wing Station 232 for gaps between adjacent layers of structure by removing the two fasteners shown in Figure 1 of Boeing Service Bulletin 1796 (Revision 3) or later FAA approved revision) at the threshold times specified in (h) or (i), as appropriate. Shim as necessary to eliminate these gaps.

(c) On aircraft which do not have the stainless steel straps (Boeing P/N 69-27339-1, P/N 69-27339-1 and -2) installed or have had such straps installed in the field, remove the fasteners shown in Figure 1 of Boeing Service Bulletin 1796 (Revision 3 or later FAA approved revision) and conduct a one time inspection for abrasion on the trailing edge of the wing skin and around the fastener holes at wing stations 211 and 232, in accordance with eddy current or dye penetrant inspection techniques at the threshold times specified in (h) or (i), as appropriate. Surfaces found abraded are to be cleaned up in accordance with, and to the limited noted,in Part II paragraphs b and c of Boeing Service Bulletin 1796 (Revision 3 or later FAA approved revisions) or a method approved by Chief, Aircraft Engineering Division, FAA Western Region.

(d) Unless already accomplished, wings which have been repaired in accordance with Boeing Service Bulletin 1796 (Revision 2) for cracks at wing station 211, must have the internal crack stop plate installed in accordance with Figure 3 of Boeing Service Bulletin 1796 (Revision 3 or later FAA approved revision) or equivalent installation approved by the Chief, Aircraft Engineering Division, FAA Western Region, within 6000 hours time in service after that repair.

(e) Cracks not exceeding 1.25 inches in length measured from the trailing edge of the wing skin may be repaired in accordance with (d), Note 2, or Part I of Boeing Service Bulletin 1796 (Revision 3 or later FAA approved revision) or an equivalent repair approved by Chief, Aircraft Engineering Division, FAA Western Region, and the airplane continued in service for the next 200 hours if inspections utilizing eddy current inspection techniques for crack growth are accomplished prior to each day's operation. If crack growth is found, repair prior to further flight in accordance with (f) or (g), as appropriate. If crack growth is not found, the aircraft must be repaired within the aforementioned 200 hours in accordance with (f).

(f) Cracks not exceeding 3.0 inches in length should be repaired in accordance with Part II of Boeing Service Bulletin 1796 (Revision 3 or later FAA approved revision) or an equivalent repair approved by the Chief, Aircraft Engineering Division, FAA Western Region.

(g) If cracks exceed 3.0 inches in length, accomplish the modification described in Boeing Service Bulletin 2607, or repair in accordance with a method approved by the Chief, Aircraft Engineering Division, FAA Western Region.

(h) For those aircraft having less than 7500 hours time in service on the effective date ofthis AD, prior to the accumulation of 7700 hours time in service and at intervals thereafter not to exceed 100 hours time in service from the last inspection.

(i) For those aircraft having 7500 or more hours time in service on the effective date of this AD, within the next 200 hours time in service and at intervals thereafter not to exceed 100 hours time in service from the last inspection.

(j) Inspections required by this AD may be discontinued when wings have been modified in accordance with:

Boeing Service Bulletin 1796, Part II, Revision 3, or later FAA approved revision Boeing Drawing 65-68328 Boeing Service Bulletin 1796, Part III, Revision 3, or later FAA approved revisions Boeing Service Bulletin 2427, Part X Boeing Service Bulletin 2607 Or another method approved by the Chief, Aircraft Engineering Division, FAA Western Region.

(k) Airplanes having cracks which require rework under this AD may be flown in accordance with FAR 21.197 with the concurrence of the Chief, Aircraft Engineering Division, FAA Western Region, to a base where rework can be accomplished.

(l) Upon request of an operator, an FAA maintenance inspector, subject to prior approval of the Chief, Aircraft Engineering Division, FAA Western Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established period of the operator if the request contains substantiating data to justify the increase for such operator.

This supersedes Amendment 752, Part 507 (29 F.R. 7923), AD 64-14-01.

This amendment becomes effective October 25, 1968.