AD 2014-24-05 Airworthiness Directives; The Boeing Company Airplanes

Models named: 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-300, 747-400, 747-400D, 747SR series. Read the applicability below — it usually turns on serial or part numbers too.

This AD applies to The Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-300, 747-400, 747-400D, and 747SR series airplanes, certificated in any category, identified as Group 4 airplanes in Boeing Special Attention Service Bulletin 747-53-2460, Revision 2, dated December 22, 2010, except airplanes that have been converted to an all-cargo configuration. Also, the requirements of this AD are applicable when a converted airplane operating in an all-cargo configuration is converted back to a passenger or passenger/cargo configuration.

Comply with this AD within the compliance times specified, unless already done.

For Group 4 airplanes identified in Boeing Special Attention Service Bulletin 747-53-2460, Revision 2, dated December 22, 2010, that have not been previously inspected or changed in accordance with Boeing Special Attention Service Bulletin 747-53-2460, Revision 1, dated February 13, 2007: Before the accumulation of 1,500 total flight cycles, or within 1,000 flight cycles after the effective date of this AD, whichever occurs later, do a material type inspection to determine if the lower forward corner reveal is made from 6061 machined aluminum plate or 356 aluminum casting, in accordance with Part 6 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 747-53-2460, Revision 2, dated December 22, 2010. Doing the inspection specified in this paragraph terminates the inspections required by paragraph (j) of AD 2008-18-07, Amendment 38-15664 (73 FR 56960, October 1, 2008), for that airplane only. (1) If, during any inspection required by paragraph (g) of this AD, any corner reveal is found to be a casting: Before the accumulation of 7,000 total flight cycles; within 2,000 flight cycles after the effective date of this AD; or within 3,000 flight cycles after the most recent inspection of the number 3 MED corner reveal was done in accordance with Boeing Service Bulletin 747-53A2378, Revision 4, dated June 10, 2010; whichever occurs later; do a detailed inspection for cracking of the corner reveal, in accordance with Part 2 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 747-53-2460, Revision 2, dated December 22, 2010. Repeat the inspection for cracking thereafter at intervals not to exceed 3,000 flight cycles until a new two-piece reveal is installed in accordance with the requirements of paragraph (g)(1)(i) of this AD. If any cracking is found, do the actions specified in paragraph (g)(1)(i) or (g)(1)(ii) of this AD. (i) Replace the cast reveal with a new 6061 machined aluminum two-piece corner reveal, before further flight, in accordance with Part 3 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 747-53-2460, Revision 2, dated December 22, 2010. (ii) Repair all cracking, before further flight, in accordance with Part 4 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 747-53-2460, Revision 2, dated December 22, 2010. (2) If, during any inspection required by paragraph (g) of this AD, a corner reveal is found that is not a casting: Before further flight, do a detailed inspection for a sharp edge, in accordance with Part 1 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 747-53-2460, Revision 2, dated December 22, 2010; and do a detailed inspection for cracking of the corner reveal, in accordance with Part 2 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 747-53-2460, Revision 2, dated December 22, 2010. Repeat the inspection for cracking thereafter at intervals not to exceed 6,000 flight cycles until the corner reveal is replaced with a 6061 machined aluminum two-piece corner reveal in accordance with the requirements of paragraph (j) of this AD. (i) If any sharp edge is found during any inspection required by paragraph (g)(2) of this AD, before further flight, rework the corner reveal, in accordance with Part 1 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 747-53-2460, Revision 2, dated December 22, 2010. (ii) If any cracking is found during any inspection required by paragraph (g)(2) of this AD, before further flight, replace the corner reveal with a 6061 machined aluminum two-piece corner reveal, in accordance with Part 3 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 747-53-2460, Revision 2, dated December 22, 2010.

This AD was prompted by a report of a cracked reveal made from a casting found within a group of airplanes that should only have machined reveals made from 6061 aluminum. We are issuing this AD to detect and correct fatigue cracking of the lower forward corner reveal of the number 3 main entry doors (MEDs), which could lead to the door escape slide departing the airplane when the door is opened and the slide is deployed, and consequent injuries to passengers and crew using the door escape slide during an emergency evacuation.

Certain requirements of this AD terminate certain requirements of AD 2008-18-07, Amendment 39-15664 (73 FR 56960, October 1, 2008).