AD 96-25-01 Airworthiness Directives; Boeing Model 747 Series Airplanes

Models named: 747 series. Read the applicability below — it usually turns on serial or part numbers too.

Model 747 series airplanes having line positions 1 through 886; equipped with Pratt & Whitney JT9D-3, -7, and -70 series engines, General Electric CF6-45/-50 series engines, or Rolls Royce RB211 series engines; certificated in any category. Note 1: Except as described in Note 2 of this AD, this AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (h) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it. Note 2: This AD does not apply to any airplane on which the strut midspar fittings have been modified in accordance with Boeing Service Bulletin 747-54-2118, which was originally released on July 25, 1986. In addition, this AD does not apply to any airplane on which the strut/wing modification has been accomplished in accordance with the following Boeing service bulletins: 1. Boeing Alert Service Bulletin 747-54A2157, dated January 12, 1995; Revision 1, dated August 3, 1995; or Revision 2, dated November 14, 1996; 2. Boeing Alert Service Bulletin 747-54A2158, dated November 30, 1994; Revision 1, dated August 17, 1995; or Revision 2, dated August 15, 1996; or 3. Boeing Alert Service Bulletin 747-54A2159, dated November 3, 1994; Revision 1, dated June 1, 1995; or Revision 2, dated March 14, 1996.

Required as indicated, unless accomplished previously. To prevent drooping of the strut at the strut-to-wing interface, and consequent separation of the engine and strut from the airplane due to cracking or fracturing of the midspar fitting clevis, accomplish the following: (a) For all airplanes: Prior to the accomplishment of each inspection required by paragraphs (b), (c), (d), and (e) of this AD, perform a visual inspection to detect any broken sealant common to the lower horizontal clevis of the inboard (for all airplanes) and the outboard (for Group 1 airplanes identified in Boeing Alert Service Bulletin 747-54A2179, dated June 27, 1996) midspar fittings, and of the fasteners, in accordance with normal maintenance practices. (1) If no broken sealant is detected, prior to further flight, remove the existing sealant in accordance with normal maintenance practices, and perform the inspections required by paragraph, (b), (c), (d), and/or (e) of this AD, as applicable, at the times specified in the applicable paragraph. Thereafter, prior to further flight following completion of each inspection required by paragraph (b), (c), (d), and/or (e) of this AD; reapply sealant to any area where the existing sealant was removed or disturbed, in accordance with Boeing 747 Maintenance Manual 51-31-01, or apply corrosion inhibitive compound BMS 3-23 in accordance with Boeing 747 BSOP 20- 41-05. (2) If any broken sealant is detected, prior to further flight, remove the existing sealant and perform a visual inspection of the fitting to detect corrosion of the fitting and check for loose fasteners by attempting to rotate them or move them upward with finger pressure. (i) If no corrosion or loose fastener is detected, perform the inspections required by paragraph (b), (c), (d), and/or (e) of this AD, as applicable, at the times specified in the applicable paragraph. Thereafter, prior to further flight following completion of each inspection required by paragraph (b), (c), (d), and/or (e) of this AD: Reapply sealant to any area where the existing sealant was removed or disturbed, in accordance with Boeing 747 Maintenance Manual 51-31-01, or apply corrosion inhibitive compound BMS 3-23 in accordance with Boeing 747 BSOP 20-41-05. (ii) If any corrosion or loose fastener is detected, prior to further flight, repair in accordance with a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. (b) For all airplanes: Perform a detailed visual borescope inspection to detect cracking, corrosion, and fracturing of the lower horizontal clevis of both midspar fittings of the inboard struts, in accordance with Boeing Alert Service Bulletin 747- 54A2179, dated June 27, 1996, at the time specified in paragraph (b)(1), (b)(2), or (b)(3), as applicable. (1) For Groups 1 and 6 airplanes, as identified in the alert service bulletin: Perform the inspection at the time specified in paragraph (b)(1)(i) or (b)(1)(ii), as applicable. (i) Within 150 flight cycles or 60 days after the effective date of this AD, whichever occurs first. Or [[Page 66205]] (ii) If terminating action has been accomplished in accordance with Boeing Service Bulletin 747-54-2118, Revision 1, dated May 21, 1987; Revision 2, dated April 21, 1988; Revision 3, dated September 29, 1988; or Revision 4, dated May 11, 1989; within the last 500 flight cycles prior to the effective date of this AD: Perform the inspection required by this paragraph within 500 flight cycles or 12 months after the effective date of this AD, whichever occur first. (2) For Group 2, 3, and 4 airplanes, as identified in the alert service bulletin: Perform the inspection at the time specified in paragraph (b)(2)(i) or (b)(2)(ii), as applicable. (i) Within 150 flight cycles or 60 days after the effective date of this AD, whichever occurs first. Or (ii) If terminating action has been accomplished in accordance with Boeing Service Bulletin 747-54-2118, Revision 1, dated May 21, 1987; Revision 2, dated April 21, 1988; Revision 3, dated September 29, 1988; or Revision 4, dated May 11, 1989; within the last 1000 flight cycles prior to the effective date of this AD: Perform the inspection within 1000 flight cycles or 12 months after the effective date of this AD, whichever occurs first. (3) For Group 5 airplanes, as identified in the alert service bulletin: Perform the inspection at the time specified in paragraph (b)(3)(i) or (b)(3)(ii), as applicable. (i) Within 150 flight cycles or 60 days after the effective date of this AD, whichever occurs first. Or (ii) If terminating action has been accomplished in accordance with Boeing Service Bulletin 747-54-2118, Revision 1, dated May 21, 1987; Revision 2, dated April 21, 1988; Revision 3, dated September 29, 1988; or Revision 4, dated May 11, 1989; within the last 800 flight cycles prior to the effective date of this AD: Perform the inspection within 800 flight cycles or 12 months after the effective date of this AD, whichever occurs first. (c) For Group 1 airplanes, as identified in Boeing Alert Service Bulletin 747-54A2179: Perform a detailed visual borescope inspection to detect cracking, corrosion, and fracturing of the lower horizontal clevis of both midspar fittings of the outboard struts, in accordance with Boeing Alert Service Bulletin 747-54A2179, dated June 27, 1996, at the time specified in paragraph (c)(1) or (c)(2) of this AD, as applicable. (1) Within 200 flight cycles or 60 days after the effective date of this AD, whichever occurs first. Or (2) If terminating action has been accomplished in accordance with Boeing Service Bulletin 747-54-2118, Revision 1, dated May 21, 1987; Revision 2, dated April 21, 1988; Revision 3, dated September 29, 1988; or Revision 4, dated May 11, 1989; within the last 1,000 flight cycles prior to the effective date of this AD: Perform the inspection within 1,000 flight cycles or 12 months after the effective date of this AD, whichever occurs first. (d) For all airplanes: Repeat the inspections of the inboard struts, as specified in paragraph (b) of this AD, at the time specified in paragraph (d)(1) or (d)(2), as applicable, until the terminating action specified in paragraph (f) or (g) of this AD, as applicable, has been accomplished. (1) For Groups 1 and 6 airplanes: Repeat the inspections at the time specified in either paragraph (d)(1)(i) or (d)(1)(ii) of this AD, as applicable. (i) Inspect thereafter at intervals not to exceed 150 flight cycles or 3 months, whichever occurs first. Or (ii) If the aft two fastener holes have been oversized, an eddy current inspection of the remaining holes has been performed, and fasteners have been installed wet with BMS 5-95 in accordance with Boeing Service Bulletin 747-54-2118, Revision 1, dated May 21, 1987; Revision 2, dated April 21, 1988; Revision 3, dated September 29, 1988; or Revision 4, dated May 11, 1989: Inspect thereafter at intervals not to exceed 150 flight cycles. (2) For Groups 2, 3, 4, and 5 airplanes: Repeat the inspections at the time specified in either paragraph (d)(2)(i) or (d)(2)(ii) of this AD, as applicable. (i) Inspect thereafter at intervals not to exceed 300 flight cycles or 6 months, whichever occurs first. Or (ii) If the aft two fastener holes have been oversized, an eddy current inspection of the remaining holes has been performed, and fasteners have been installed wet with BMS 5-95 in accordance with Boeing Service Bulletin 747-54-2118, Revision 1, dated May 21, 1987; Revision 2, dated April 21, 1988; Revision 3, dated September 29, 1988; or Revision 4, dated May 11, 1989: Inspect thereafter at intervals not to exceed 300 flight cycles. (e) For Group 1 airplanes: Repeat the inspection of the outboard struts, as required by paragraph (c) of this AD, at the times specified in either paragraph (e)(1) or (e)(2) of this AD, as applicable. (1) Inspect thereafter at intervals not to exceed 300 flight cycles or 6 months, whichever occurs first. Or (2) If the aft two fastener holes have been oversized, an eddy current inspection of the remaining holes has been performed, and fasteners have been installed wet with BMS 5-95 in accordance with Boeing Service Bulletin 747-54-2118, Revision 1, dated May 21, 1987; Revision 2, dated April 21, 1988; Revision 3, dated September 29, 1988; or Revision 4, dated May 11, 1989: Inspect thereafter at intervals not to exceed 300 flight cycles. (f) For all airplanes: If any cracking, corrosion, or fracturing is detected during any inspection required by this AD, and it is outside the limits specified in Boeing Service Bulletin 747-54-2118, Revision 4, dated May 11, 1989: Prior to further flight, accomplish the requirements of either paragraph (f)(1) or (f)(2) of this AD. Following accomplishment of those actions, no further action is required by this AD. (1) Accomplish the strut/wing modification specified in paragraph (f)(1)(i), (f)(1)(ii), or (f)(1)(iii) of this AD, as applicable. (i) For airplanes equipped with Rolls Royce Model RB211 series engines: Accomplish the strut/wing modification in accordance with Boeing Alert Service Bulletin 747-54A2157, Revision 2, dated November 14, 1996. Accomplishment of this paragraph also terminates the requirements of AD 95-13-05, amendment 39-9285. (ii) For airplanes equipped with General Electric Model CF6-45 or -50 series engines or Pratt & Whitney Model JT9D-70 series engines: Accomplish the strut/wing modification in accordance with Boeing Alert Service Bulletin 747-54A2158, Revision 2, dated August 15, 1996. Accomplishment of this paragraph also terminates the requirements of AD 95-13-07, amendment 39-9287. (iii) For airplanes equipped with Pratt & Whitney Model JT9D series engines (excluding Model JT9D-70 engines): Accomplish the strut/wing modification, in accordance with Boeing Alert Service Bulletin 747-54A2159, Revision 2, dated March 14, 1996. Accomplishment of this paragraph also terminates the requirements of AD 95-10-16, amendment 39-9233. (2) Replace the midspar fittings of the strut with new or serviceable fittings in accordance with Boeing Service Bulletin 747- 54-2118, Revision 4, dated May 11, 1989. (g) For all airplanes: If any cracking or corrosion is detected during any inspection required by this AD that is within the limits specified in Boeing Service Bulletin 747-54-2118, Revision 4, dated May 11, 1989: Prior to further flight, accomplish the requirements of either paragraph (g)(1), (g)(2), or (g)(3) of this AD. (1) For Group 2, 3, 4, and 5 airplanes: Rework both the upper and lower horizontal clevis of the midspar fittings of each inboard strut, and for Group 1 airplanes, rework both the upper and lower horizontal clevis of the midspar fittings of each inboard and outboard strut, in accordance with Boeing Service Bulletin 747-54- 2118, Revision 1, dated May 21, 1987; Revision 2, dated April 21, 1988; Revision 3, dated September 29, 1988; or Revision 4, dated May 11, 1989. Accomplishment of the requirements of this paragraph constitute terminating action for the requirements of this AD provided that the actions specified in paragraphs (g)(1)(i), (g)(1)(ii), (g)(1)(iii), and (g)(1)(iv) are also accomplished. (i) The rework shall be accomplished on all holes of the horizontal flanges; (ii) The rework shall include an eddy current inspection of all holes at the horizontal flanges, in accordance with Boeing Non- Destructive Testing (NDT) Manual D6-7170 Part 6, Subject 51-00-00, Figure 19. (iii) All holes of the horizontal flanges shall be oversized and insurance cut an additional 0.0312 inch, in accordance with Boeing Service Bulletin 747-54-2118, Revision 4, dated May 11, 1989. And (iv) One coat of BMS 10-11 Type 1 primer shall be applied to the fastener holes, and the oversized fasteners shall be installed wet with BMS 5-95 sealant, in accordance with Boeing Service Bulletin 747-54-2118, Revision 4, dated May 11, 1989. (2) For Group 2, 3, 4, and 5 airplanes: Rework both the upper and lower horizontal clevis of the midspar fittings of each inboard strut, and for Group 1 airplanes, rework both the upper and lower horizontal clevis of the [[Page 66206]] midspar fittings of each inboard and outboard strut, in accordance with Boeing Service Bulletin 747-54-2118, dated July 25, 1986. Accomplishment of the requirements of this paragraph constitute terminating action for the requirements of this AD. (3) Accomplish the rework (removal of cracking and corrosion) specified in Boeing Service Bulletin 747-54-2118, Revision 4, dated May 11, 1989, with the exception that eddy current inspections specified in that service bulletin must be accomplished in accordance with Boeing Non-Destructive Testing (NDT) Manual D6-7170 Part 6, Subject 51-00-00, Figure 19. Thereafter, repeat the inspections specified in paragraph (d) or (e) of this AD, as applicable, at the time required by the applicable paragraph. (h) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Seattle ACO. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO. Note 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO. (i) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. (j) Certain actions shall be done in accordance with the Boeing Alert Service Bulletins listed in the following table. The incorporation by reference of those documents was approved previously by the Director of the Federal Register, in accordance with 5 U.S.C. 552(a) and 1 CFR part 51, as of the dates specified in the table below: ---------------------------------------------------------------------------------------------------------------- Referenced service bulletin and date Approval date and Federal Register citation ---------------------------------------------------------------------------------------------------------------- 747-54A2157, January 12, 1995........... July 28, 1995 (60 FR 33333, June 28, 1995). 747-54A2158, November 30, 1994.......... July 28, 1995 (60 FR 33336, July 28, 1995). 747-54A2159, November 3, 1994........... June 21, 1995 (60 FR 27008, May 22, 1995). ---------------------------------------------------------------------------------------------------------------- Certain other actions shall be done in accordance with the following Boeing service bulletins, which contain the specified effective pages: ---------------------------------------------------------------------------------------------------------------- Revision Service bulletin referenced and date Page No. level shown Date shown on page on page ---------------------------------------------------------------------------------------------------------------- Alert 747-54A2179, June 27, 1996...... 1-34................... (\1\) June 27, 1996. 747-54A2157, Revision 1, August 3, 1-901.................. 1 August 3, 1995. 1995. 747-54A2157, Revision 2, November 14, 1-961.................. 2 November 14, 1996. 1996. 747-54A2158, Revision 1, August 17, 1-1,052................ 1 August 17, 1995. 1995. 747-54A2158, Revision 2, August 15, 1-1,080D2.............. August 15, 1996. 1996. 747-54A2159, Revision 1, June 1, 1995. 1-1,240................ 1 June 1, 1995. 747-54A2159, Revision 2, March 14, 1-1,298................ 2 March 14, 1996. 1996. 747-54-2118, July 25, 1986............ 1-172.................. (\1\) July 25, 1986. Notice of Status Change, 747-54-2118 1...................... (\1\) October 5, 1986. NSC 1, October 5, 1986. 747-54-2118, Revision 1, May 21, 1987. 1-175.................. 1 May 21, 1987. 747-54-2118, Revision 2, April 21, 1-5, 7-13, 17-21, 24, 2 April 21, 1988. 1988. 30, 31, 38, 39, 48-51, 58, 59, 61, 69-72, 84, 101, 117, 134, 151, 170. 6, 14-16, 22, 23, 26- 1 May 21, 1987. 29, 32-37, 40-47, 52- 57, 60, 62-68, 73-83, 85-100, 102-116, 118- 133, 135-150, 152-169, 171-175. 25..................... (\1\) July 25, 1986. 747-54-2118, Revision 3, September 29, 1-6, 9, 10, 12, 21, 22. 3 September 29, 1988. 1988. 7, 8, 13-20, 23, 24, 26- 1 May 21, 1987. 175. 11..................... 2 April 21, 1988. 25..................... (\1\) July 25, 1986. 747-54-2118, Revision 4, May 11, 1989. 1-12, 16, 17, 21-170, 4 May 11, 1989. 173, 174. 13, 18-20.............. 2 April 21, 1988. 14, 15................. 1 May 21, 1987. 171, 172, 175, 176..... \1\ July 25, 1986. ---------------------------------------------------------------------------------------------------------------- \1\ Original. The incorporation by reference of those documents was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124- 2207. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. (k) This amendment becomes effective on January 2, 1997. Issued in Renton, Washington, on November 25, 1996. Darrell M. Pederson, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 96-30685 Filed 12-16-96; 8:45 am] BILLING CODE 4910-13-U