AD 86-11-06

86-11-06 BOEING: Amendment 39-5327. Applies to Model 707 and 720 series airplanes, certificated in any category, with 15,000 or more landings. To ensure continued structural integrity of the wing front spar upper chord, accomplish the following within 100 landings or 60 days after the effective date of this AD, whichever occurs first, unless previously accomplished within the last 900 landings or 305 days:

A. Perform a close visual inspection of the wing front spar upper chord for cracks and corrosion in accordance with Boeing Service Bulletin 3240, Revision 1, dated November 13, 1981, or later FAA-approved revision. Repeat the inspection at intervals not to exceed 1,000 landings or one year, whichever occurs first.

B. If cracks or corrosion areas are found, repair prior to further flight in accordance with Boeing Service Bulletin 3240, Revision 3, dated October 18, 1985, or later FAA-approved revision.

C. Cracks which have been repaired in accordance with the "stop drilling" procedure described in Part III, Figure 2, of Service Bulletin 3240, Revision 1, dated November 13, 1981, or later FAA-approved revision, must be visually inspected at intervals not exceeding 300 landings, until permanently repaired in accordance with Part III, Figure 2, of Service Bulletin 3240, Revision 3, dated October 18, 1985, or later FAA-approved revision. A permanent repair must be completed within 1,000 landings or one year, whichever occurs first after the effective date of this AD.

D. Cracks greater than 2.0 inches in length, which have been previously repaired in accordance with Boeing Service Bulletin 3240, Revision 2, dated May 3, 1985, or earlier, must be repaired in accordance with Revision 3, dated October 18, 1985, or later FAA-approved revision, within 1,000 landings or one year, whichever occurs first after the effective date of this AD.

E. After each of the above inspections and repairs have been performed, apply BMS-3-23 corrosion inhibitor, or equivalent, to the affected areas.

F. Alternate means of compliance or adjustment of the compliance time, which provide an acceptable level of safety, may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain 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 the inspections and/or modifications required by this AD.

All persons affected by this proposal who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to the Boeing Commercial Airplane Company, P.O. Box 3707, Seattle, Washington 98124. These documents may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington.

This AD supersedes AD 85-08-07, Amendment 39-5044. This amendment becomes effective July 14, 1986.