60-02-01 BOEING: Amdt. 39-803. Part 39 of the Federal Aviation Regulations. Amendment 80 (25 F.R. 336), (AD-60-02-01) as amended by Amendment 39-58 (30 F.R. 5827) 60-02-01 and 39-632 is further amended by Amendment 39-803. Applies to the following 707-100 Series aircraft only: Serial Numbers 17586 through 17591, 17609, 17610, 17628 through 17638, 17640, 17641, 17658 through 17667, and 17696. \n\n\tThe occurrence of cracks in seven wing splice plates on early 707-100 Series aircraft, and the subsequent cracking of two plates in service, one after 1,150 flight hours, has led to further investigations which indicate that the plates used in early production can be expected to crack after certain periods of calendar and/or service time. These plates are installed on wing lower surface at RBL 70.5 and LBL 70.5. Improved plates have been installed on airplanes other than noted above. \n\n\tThe following inspections must be conducted until improved plates are installed at which time these special inspections are no longer required. \n\n\t(a) Unless already accomplished within that last four months or 750 hours' time in service, within the next 200 to 400 hours' time in service: \n\n\t\t(1) Remove left-and right-hand lower wing-body fairings. \n\n\t\t(2) Visually inspect all wing lower splice plates for cracks at RBL 70.5 and LBL 70.5. \n\n\t\t(3) Replace any splice plate found to be cracked, with Boeing redesigned plate in accordance with Boeing installation procedures. \n\n\t(b) For aircraft with less than 12,000 hours' time in service, repeat the inspections of original plates as described in (a) at intervals not to exceed 750 hours' time in service from the last inspection. \n\n\t(c) For aircraft with 12,000 or more hours' time in service, repeat the inspection of original plates as described in paragraph (a) at intervals not to exceed 8000 hours' time in service from the last inspection. \n\n\t(d) Upon request of the operator, an FAA maintenance inspector, subject toprior 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 inspection period of the operator if the request contains substantiating data to justify the increase for such operator. \n\n\t(e) Aircraft which have accumulated 25,000 or more flight hours do not require further inspections under this Airworthiness Directive. \n\n\tThis AD supersedes AD 59-13-05. \n\n\t(Boeing Service Bulletin No. 186 (R-1) covers this same subject.) \n\n\tRevised April 27, 1965. \n\n\tRevised July 25, 1969.