67-10-01 BOEING: Amdt. 39-379 Part 39 Federal Register April 1, 1967. Applies to Model 707-100 Series, 707-200 Series, and 720 Series Airplanes Listed in Boeing Service Bulletin No. 2177(R-2). \n\n\tCompliance required as indicated. \n\n\tIn order to detect and repair cracks in the wing skin and the horizontal legs of the splice angle and chord members at Wing Station 304.93 rear spar upper chord splice, accomplish the following: \n\n\t(a)\tWithin the next 150 hours' time in service after the effective date of this AD, unless already accomplished within the last 200 hours' time in service, and thereafter at intervals not to exceed 350 hours' time in service from the last inspection, inspect Model 720 Series airplanes with 8,200 or more hours' time in service on the effective date of this AD and Model 707 Series airplanes with 15,200 or more hours' time in service on the effective date of this AD in accordance with (d).\n \n\t(b)\tBefore the accumulation of 8,350 hours' time in service, unless already accomplished within the last 350 hours' time in service, and thereafter at intervals not to exceed 350 hours' time in service from the last inspection, inspect Model 720 Series airplanes with less than 8,200 hours' time in service on the effective date of this AD in accordance with (d). \n\n\t(c)\tBefore the accumulation of 13,350 hours, time in service, unless already accomplished within the last 350 hours' time in service, and thereafter at intervals not to exceed 350 hours' time in service from the last inspection, inspect Model 707 Series airplanes with less than 15,200 hours' time in service on the effective date of this AD in accordance with (d). \n\n\t(d)\tVisually inspect for cracks in accordance with the "Visual Inspection Procedure" of Paragraph 3, Part I, Boeing Service Bulletin No. 2177(R-2) or later FAA-approved revision.\n \n\t(e)\tWithin the next 100 hours' time in service after the effective date of this AD, unless already accomplished within the last 600 hours'time in service, and thereafter at intervals not to exceed 700 hours' time in service from the last inspection, inspect Model 720 Series airplanes with 8,600 or more hours' time in service on the effective date of this AD and Model 707 Series airplanes with 15,600 or more hours' time in service on the effective date of this AD in accordance with (h).\n \n\t(f)\tBefore the accumulation of 8,700 hours' time in service, unless already accomplished within the last 700 hours' time in service, and thereafter at intervals not to exceed 700 hours' time in service from the last inspection, inspect Model 720 Series airplanes with less than 8,600 hours' time in service on the effective date of this AD in accordance with (h).\n\n\t(g)\tBefore the accumulation of 15,700 hours' time in service, unless already accomplished within the last 700 hours' time in service, and thereafter at intervals not to exceed 700 hours' time in service from the last inspection, inspect Model 707 Series airplanes with lessthan 15,600 hours' time in service on the effective date of this AD in accordance with (h).\n \n\t(h)\tAccomplish an ultrasonic and x-ray inspection in accordance with Paragraph 3, Part I, Boeing Service Bulletin No. 2177(R-2) or later FAA-approved revision or in accordance with a method approved by the chief, Aircraft Engineering Division, FAA Western Region.\n \n\t(i)\tIf a crack is found during the inspection conducted in accordance with (d) or (h), and that crack does not extend further than 8 inches forward of the seal stop hole centerline, repair or modify the affected parts before further flight (except that the airplane may be flown in accordance with FAR 21.197 to a base where the repair or modification can be performed) by accomplishing one of the repairs of modifications specified in subparagraphs (1) through (6) of this paragraph or in accordance with a method approved by the Chief, Aircraft Engineering Division, FAA Western Region. In the case of a crack extending further than 8 inches forward of the seal stop hole centerline, repair or modify the affected parts before further flight (except that the airplane may be flown in accordance with FAR 21.197 to a base where the repair or modification can be performed) in accordance with a method approved by the Chief, Aircraft Engineering Division, FAA Western Region. \n\n\t\t(1)\tComplete preventive modification applicable to Model 707 and 720 Series airplanes in accordance with the crack length limitations and procedures of Paragraph 3, Part II, "Preventive Modification Data", Boeing Service Bulletin No. 2177(R-3) or later FAA-approved revision.\n \n\t\tNOTE. - The "Preventive Modification" specified in Paragraph 3, Part II, "Preventive Modification Data", of Revision 2 of Boeing Service Bulletin 2177 is a "Complete Preventive Modification" as used in (i)(1). \n\n\t\t(2)\tComplete preventive modification minus coldworking applicable to Model 720 Series airplanes only in accordance with the crack length limitations andprocedures of Paragraph 3, Part II, "Preventive Modification Data", Boeing Service Bulletin No. 2177(R-4) or later FAA- approved revision. \n\n\t\t(3)\tOptional partial preventive modification applicable to Model 720 Series airplanes only in accordance with the crack length limitations and procedures of Paragraph 3, Part II, "Preventive Modification Data", Boeing Service Bulletin No. 2177(R-3), or later FAA- approved revision. \n\n\t\t(4)\tWing structure improvement program applicable to Model 720 Series airplanes only in accordance with the procedures of Boeing Document 65-12700. \n\n\t\t(5)\tCrack repair applicable to Model 707 and 720 Series airplanes in accordance with the crack length limitations and procedures of Paragraph 3, Part III, "Crack Repair Data", Boeing Service Bulletin No. 2177(R-2) or later FAA-approved revision. \n\n\t\t(6)\tCrack repair minus coldworking applicable to Model 720 Series airplanes only in accordance with the crack length limitations and procedures for Paragraph 3,Part III, "Crack Repair Data", Boeing Service Bulletin No. 2177(R-4) or later FAA-approved revision. \n\n\tUpon the completion of a particular repair or modification specified in subparagraphs (1) through (6) of this paragraph, comply with (n) through (s) as appropriate to the type of repair or modification performed under this paragraph.\n \n\t(j)\tWithin the next 7,000 hours' time in service after December 15, 1966, modify Model 720 Series airplanes with 8,000 or more hours' time in service on December 15, 1966, and Model 707 Series airplanes with 15,000 or more hours' time in service on December 15, 1966, in accordance with (m). \n\n\t(k)\tBefore the accumulation of 15,000 hours' time in service after December 15, 1966, modify Model 720 Series airplanes with less than 8,000 hours' time in service on December 15, 1966, in accordance with (m).\n\n\t(l)\tBefore the accumulation of 22,000 hours' time in service after December 15, 1966, modify Model 707 Series airplanes with less than 15,000 hours' time in service on December 15, 1966, in accordance with (m).\n \n\t(m)\tUnless already accomplished in accordance with (i)(1), (2), (3), (4) or (5) or in accordance with a method approved by the Chief, Aircraft Engineering Division, FAA Western Region, accomplish one of the following:\n \n\t\t(1)\tComplete preventive modification specified in (i)(1); \n\n\t\t(2)\tComplete preventive modification minus coldworking specified in (i)(2). \n\n\t\t(3)\tOptional partial preventive modification specified in (i)(3); or \n\n\t\t(4)\tWing structure improvement program specified in (i)(4). \n\n\tUpon the completion of a particular modification specified in subparagraphs (1) through (4) of this paragraph, comply with (p) through (s) as appropriate to the type of modification performed under this paragraph.\n \n\t(n)\tUpon the completion of the crack repair specified in (i)(5), the repetitive inspections required by (d) through (h) may be discontinued.\n \n\t(o)\tUpon the completion of the crack repair minus coldworking specified in (i)(6), accomplish either the wing structure improvement program specified in (i)(4) or an x-ray inspection specified in (h) (in lieu of the other modifications specified in subparagraphs (1), (2) and (3) of (m)) prior to the accumulation of 10,000 hours' time in service after completion of the repair. If an x-ray inspection is performed under this paragraph, accomplish additional x-ray inspections within each successive period not to exceed 2,000 hours' time in service from the last inspection. The x-ray inspections required by this paragraph may be discontinued when the wing structure improvement program is accomplished.\n \n\t(p)\tUpon completion of the complete preventive modification specified in (i)(1), the repetitive inspections required by (d) and (h) may be discontinued. \n\n\t(q)\tUpon completion of the wing structure improvement program specified in (i)(4), the repetitive inspections required by (d) and (h) may be discontinued. \n\n\t(r)\tUpon completion of the optional partial preventive modification specified in (i)(3), perform an x-ray inspection specified in (h) within 2,000 hours' time in service from the completion of the modification and thereafter within periods not to exceed 2,000 hours' time in service from the last inspection. Prior to the accumulation of 7,000 hours' time in service after the completion of the optional partial preventive modification, accomplish either the complete preventive modification specified in (i)(1) or the wing structure improvement program specified in (i)(4). \n\n\t(s)\tUpon completion of the complete preventive modification minus coldworking specified in (i)(2), accomplish either the wing structure improvement program specified in (i)(4) or an x-ray inspection specified in (h) prior to the accumulation of 10,000 hours' time in service after completion of the modification. If an x-ray inspection is performed under this paragraph, accomplish additional x-ray inspections within each successive period not to exceed 2,000 hours' time in service from the last inspection. The x-ray inspections required by this paragraph may be discontinued when the wing structure improvement program is accomplished. \n\n\t(t)\tUpon request of the operator, an FAA maintenance inspector, subject to prior approval by the Regional Director, FAA Western Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for that operator. \n\n\tThis supersedes AD 66-29-02.\n\n\tThis directive effective April 1, 1967.