Airworthiness Directive · Amendment 39-14095 · Boeing Model 747-100, -100B, -100B SUD, -200B, -200C, -300, -400, and -400D Series Airplanes; and Model 747SR Series Airplanes
Boeing Model 747-100, -100B, -100B SUD, -200B, -200C, -300, -400, and -400D Series Airplanes; and Model 747SR Series Airplanes
This AD applies to Boeing Model 747-100, -100B, -100B SUD, -200B, -200C, -300, -400, and -400D series airplanes; and Model 747SR series airplanes; having line numbers 1 through 1301 inclusive; certificated in any category.
The FAA is superseding an existing airworthiness directive (AD), which applies to certain Boeing Model 747 series airplanes. That AD currently requires a one-time inspection to determine the material type of the stop support fittings of the main entry doors (MEDs). That AD also currently requires repetitive detailed inspections to detect cracks of certain stop support fittings of the MEDs, and replacement of any cracked stop support fitting with a certain new stop support fitting. This new AD adds new inspections, and replacement if necessary, of the stop support fittings of MED 3, and adds airplanes to the applicability. This AD is prompted by reports of MED 3 having certain stop support fittings that are susceptible to stress corrosion cracking. We are issuing this AD to detect and correct stress corrosion cracking of the stop support fittings of the MEDs, which could result in damage to the adjacent forward edge frame of the door and consequent loss of a MED and rapid decompression of the airplane.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
For Model 747-100, -100B, -100B SUD, -200, -200B, -200C, -300, -400, and 747SR series airplanes having line numbers 1 through 830 inclusive: Within 18 months after January 25, 1999 (the effective date of AD 98-26-13, amendment 39-10954), perform a high frequency eddy current (HFEC) inspection to determine the material type of the stop support fittings of the MEDs, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 747-53-2358, dated August 26, 1993; or Boeing Service Bulletin 747-53-2358, Revision 1, dated April 19, 2001. Perform the inspection only at those locations where the material type of the stop support fittings is unknown, as specified in Figure 3, Table 1, of either service bulletin. As of the effective date of this AD, do the actions in accordance with Boeing Service Bulletin 747-53-2358, Revision 1, dated April 19, 2001.
(1) If the fitting is made from 7075-T73 or 7050-T7451 material, no further action is required by this AD for that fitting; however, the requirements of paragraph (l) of this AD still apply.
(2) If the fitting is not made from 7075-T73 or 7050-T7451 material, before further flight, perform a detailed inspection to detect cracks of the stop support fitting of the MEDs, in accordance with the applicable service bulletin.
Note 1: For the purposes of this AD, a detailed inspection is “an intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirrors magnifying lenses, etc. may be necessary. Surface cleaning and elaborate procedures may be required.”
(i) If no crack is detected, repeat the detailed inspection thereafter at intervals not to exceed 36 months or 2,000 flight cycles, whichever occurs first.
(ii) If any crack is detected, before further flight, replace the fitting with a stop support fitting made from 7075-T73 or 7050-T7451 material, in accordance with the applicable service bulletin.
(g) For Model 747-100, -100B, -100B SUD, -200, -200B, -200C, -300, -400, and 747SR series airplanes having line numbers 1 through 830 inclusive: Replacement of the stop support fitting of the MEDs with a stop support fitting made from 7075-T73 material, in accordance with Boeing Service Bulletin 747-53-2358, dated August 26, 1993; or replacement with a stop support fitting made from 7075-T73 or 7050-T7451 material, in accordance with Boeing Service Bulletin 747-53-2358, Revision 1, dated April 19, 2001; constitutes terminating action for the repetitive inspection requirements of paragraph (f) of this AD for the replaced fitting. As of the effective date of this AD, only Boeing Service Bulletin 747-53-2358, Revision 1, dated April 19, 2001, may be used.
Note 2: Operators are not required to remove foam and inspect/drill drain holes as specified in Paragraph 3.B.1.e. and the Notes of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 747-53-2485, dated January 8, 2004, when doing any inspection required by paragraphs (h), (i), and (k) of this AD.
For Model 747-100, -100B, -100B SUD, -200B, -200C, -300, -400, and -400D series airplanes, and Model 747SR series airplanes, having line numbers 1 through 830 inclusive on which the actions specified in the Accomplishment Instructions of Boeing Service Bulletin 747-53-2358, dated August 26, 1993; or Boeing Service Bulletin 747-53-2358, Revision 1, dated April 19, 2001; have been done: Do the inspection specified in paragraph (h)(1) or (h)(2) of this AD, as applicable, at the time specified.
(1) Except as provided by paragraph (h)(2) of this AD, if any stop support fitting, 2L through 6L and 2R through 6R, of MED 3, was replaced before the effective date of this AD: Perform a one-time HFEC inspection to determine the material type of the stop support fittings of MED 3 that were replaced, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 747-53-2485, dated January 8, 2004, at the later of the times specified in paragraphs (h)(1)(i) and (h)(1)(ii) of this AD.
(i) Within 72 months after the stop support fitting of MED 3 was replaced.
(ii) Within 18 months after the effective date of this AD.
(2) If any stop support fitting, 2L through 6L and 2R through 6R, of MED 3, cannot be determined conclusively by reviewing airplane maintenance records that the fitting was not replaced, within 18 months after the effective date of this AD, perform a one-time HFEC inspection to determine the material type of the stop support fitting, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 747-53-2485, dated January 8, 2004.
(i) For airplanes having line numbers 831 through 1301 inclusive: At the later of the times specified in paragraphs (i)(1) and (i)(2) of this AD, perform a one-time HFEC inspection to determine the material type of the stop support fittings of MED 3 in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 747-53-2485, dated January 8, 2004.
(1) Before 72 months since the date of issuance of the original Airworthiness Certificate or the date of issuance of the original Export Certificate of Airworthiness.
(2) Within 18 months after the effective date of this AD.
If, during any HFEC inspection required by paragraph (h) or (i) of this AD, any fitting is found to be made of 7075-T73 or 7050-T7451 material, no further action is required by this AD for that fitting; however, paragraph (l) of this AD still applies.
If, during any HFEC inspection required by paragraph (h) or (i) of this AD, any fitting is found not to be made of 7075-T73 or 7050-T7451 material, before further flight, perform a detailed inspection for cracks of the fitting in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 747-53-2485, dated January 8, 2004.
(1) If no crack is detected, repeat the detailed inspection specified in paragraph (k) of this AD thereafter at intervals not to exceed 36 months or 2,000 flight cycles, whichever comes first. Doing the replacement specified in paragraph (k)(2) of this AD ends the repetitive inspections for the replaced fitting.
(2) If any crack is detected, before further flight, replace the fitting with a fitting made of 7075-T73 or 7050-T7451 material in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 747-53-2485, dated January 8, 2004. No further action is required by this AD for that fitting; however, paragraph (l) of this AD still applies.
As of the date specified in paragraph (l)(1) or (l)(2) of this AD, as applicable, no person shall install on any airplane a stop support fitting of the MEDs made from either 7079-T651 or 7075-T651 material.
(1) For airplanes having line numbers 1 through 830 inclusive: As of January 25, 1999.
(2) For airplanes having line numbers 831 through 1301 inclusive: As of the effective date of this AD.
