AD 70-07-02

70-07-02 BOEING: Amdt. 39-961. Applies to Model 707 and 720 Series airplanes listed in Boeing Service Bulletin No. 2961, Revision 1, or later FAA-approved revisions.

Compliance required within the next 50 hours' time in service after the effective date of this AD on aircraft having 14,000 or more flights, unless already accomplished. Aircraft having less than 14,000 flights on the effective date of this AD must be inspected after they have accrued 13,000 flights but no later than 50 hours' time in service after they have accrued 14,000 flights, unless already accomplished during this specified interval.

For the purpose of compliance with this AD, the number of flights may be determined by dividing the total flight time on an airplane by the operator's fleet average flight time per flight for the type airplane considered.

To prevent walkway panel failures between body stations 344 and 352:

(a) Inspect the left-hand and right-hand walkway panels on all airplaneslisted in Boeing Service Bulletin 2961, Revision 1, or later FAA-approved revisions. Perform inspections in accordance with Accomplishment Instruction, Part II, unless already accomplished in accordance with Service Bulletin 2961, dated 13 January 1970, or an equivalent inspection approved by the Chief, Aircraft Engineering Division, FAA Western Region.

(b) If no cracks are found, perform:

(1) The preventative modification described in Part II of Boeing Service Bulletin 2961, Revision 1, dated 11 March 1970, or later FAA-approved revisions, or

(2) Reinspections at intervals not to exceed 1500 flights in service (for eddy current or dye penetrant inspection) or 500 flights (for visual inspection) in accordance with Part II of Boeing Service Bulletin 2961, Revision 1, or

(3) An equivalent modification or inspection program approved by the Chief, Aircraft Engineering Division, FAA Western Region.

(c) If cracks are found during any of the inspections, perform the preventative modification in accordance with Part II of Boeing Service Bulletin 2961, Revision 1, 11 March 1970, or later FAA-approved revisions, or an equivalent modification approved by the Chief, Aircraft Engineering Division, FAA Western Region, prior to further flight.

Inspections required by this AD may be discontinued when the approved preventative modification has been accomplished.

This supersedes Amendment 39-932, 35 F.R. 1159, AD 70-02-12.

This amendment becomes effective March 28, 1970.