Airworthiness Directives; The Boeing Company Airplanes

DEPARTMENT OF TRANSPORTATION <SUBAGY>Federal Aviation Administration</SUBAGY> <CFR>14 CFR Part 39</CFR> <DEPDOC>[Docket No. FAA-2024-1301; Project Identifier AD-2024-00035-T]</DEPDOC> <RIN>RIN 2120-AA64</RIN> <SUBJECT>Airworthiness Directives; The Boeing Company Airplanes</SUBJECT> <HD SOURCE="HED">AGENCY:</HD> Federal Aviation Administration (FAA), DOT. <HD SOURCE="HED">ACTION:</HD> Notice of proposed rulemaking (NPRM). <SUM> <HD SOURCE="HED">SUMMARY:</HD> The FAA proposes to adopt a new airworthiness directive (AD) for certain The Boeing Company Model 787-9 and 787-10 airplanes. This proposed AD was prompted by reports that some floor beam side-of-body fittings have been manufactured with an incorrect material type. This proposed AD would require replacing the incorrectly manufactured floor beam side-of-body fittings, inspecting the fuselage frame and fastener holes for damage, and repairing any damage. The FAA is proposing this AD to address the unsafe condition on these products. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> The FAA must receive comments on this proposed AD by July 1, 2024. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods: • <E T="03">Federal eRulemaking Portal:</E> Go to <E T="03">regulations.gov.</E> Follow the instructions for submitting comments. • <E T="03">Fax:</E> 202-493-2251. • <E T="03">Mail:</E> U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590. • <E T="03">Hand Delivery:</E> Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. <E T="03">AD Docket:</E> You may examine the AD docket at <E T="03">regulations.gov</E> under Docket No. FAA-2024-1301; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this NPRM, any comments received, and other information. The street address for Docket Operations is listed above. <E T="03">Material Incorporated by Reference:</E> • For service information, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; telephone 562-797-1717; website <E T="03">myboeingfleet.com</E> . • You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206-231-3195. It is also available at <E T="03">regulations.gov</E> under Docket No. FAA-2024-1301. <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Joseph Hodgin, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3962; email: <E T="03">Joseph.J.Hodgin@faa.gov</E> . </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> <HD SOURCE="HD1">Comments Invited</HD> The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under <E T="02">ADDRESSES</E> . Include “Docket No. FAA-2024-1301; Project Identifier AD-2024-00035-T” at the beginning of your comments. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend this proposal because of those comments. Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to <E T="03">regulations.gov,</E> including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this NPRM. <HD SOURCE="HD1">Confidential Business Information</HD> CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this NPRM contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this NPRM, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as “PROPIN.” The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this NPRM. Submissions containing CBI should be sent to Joseph Hodgin, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3962; email: <E T="03">Joseph.J.Hodgin@faa.gov.</E> Any commentary that the FAA receives that is not specifically designated as CBI will be placed in the public docket for this rulemaking. <HD SOURCE="HD1">Background</HD> The FAA has received reports that some floor beam side-of-body fittings have been manufactured with an incorrect material type between station 1233 and station 1593. The incorrect material type is a grade 1 or 2 commercially pure unalloyed titanium, which has significantly reduced strength, fatigue, and damage-tolerance properties compared to the type design grade 5 Ti-6AI-4V material. The discrepant floor beam side-of-body fitting part numbers are installed on Model 787-9 and -10 airplanes. This condition, if not addressed, could result in failure of the fittings. The failure of multiple adjacent fittings may lead to inability of the surrounding principal structure elements to sustain limit loads and damage to critical systems under the floor; these conditions could cause loss of control of the airplane. Additionally, in the event of an emergency landing or full certified rapid decompression, failure of multiple adjacent fittings could result in the inability of the passenger floor grid to maintain the loads and could result in serious injury or impeded egress for passengers. <HD SOURCE="HD1">FAA's Determination</HD> The FAA is issuing this NPRM after determining that the unsafe condition described previously is likely to exist or develop on other products of the same type design. <HD SOURCE="HD1">Related Service Information Under 1 CFR Part 51</HD> The FAA reviewed Boeing Alert Requirements Bulletin B787-81205-SB530084-00 RB, Issue 001, dated December 8, 2023. This service information specifies performing an X-ray fluorescence spectrometer inspection of the floor beam side-of-body fittings between station 1233 and station 1593 to determine whether the fitting was manufactured with type design grade 5 Ti-6AI-4V material. Alternatively, operators may replace all floor beam side-of-body fittings between station 1233 and station 1593 with fittings made of the correct material without performing an X-ray fluorescence spectrometer inspection. For any floor beam side-of-body fitting that needs replacement, this service information specifies inspecting the fuselage frame and fastener holes for damage, repairing any damage, and installing a floor beam side-of-body fitting made of the correct material. This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in <E T="02">ADDRESSES</E> . <HD SOURCE="HD1">Proposed AD Requirements in This NPRM</HD> This proposed AD would require accomplishing the actions specified in the service information already described, except for any differences identified as exceptions in the regulatory text of this proposed AD. For information on the procedures and compliance times, see this service information at <E T="03">regulations.gov</E> under Docket No. FAA-2024-1301. <HD SOURCE="HD1">Costs of Compliance</HD> The FAA estimates that this AD, if adopted as proposed, would affect 60 airplanes of U.S. registry. The FAA estimates the following costs to comply with this proposed AD: <GPOTABLE COLS="5" OPTS="L2,i1" CDEF="s50,r50,12,12,r50"> <TTITLE>Estimated Costs—Option 1</TTITLE> <CHED H="1">Action</CHED> <CHED H="1">Labor cost</CHED> <CHED H="1">Parts cost</CHED> Cost on U.S. operators </CHED> <ROW> <ENT I="01">X-ray fluorescence spectrometer inspection to determine material type</ENT> <ENT>77 work-hours × $85 per hour = $6,545</ENT> <ENT>$0</ENT> <ENT>$6,545</ENT> <ENT>Up to $392,700.</ENT> </ROW> </GPOTABLE> <GPOTABLE COLS="4" OPTS="L2,i1" CDEF="s50,r50,12,12"> <TTITLE>Estimated Costs—Option 2</TTITLE> <CHED H="1">Action</CHED> <CHED H="1">Labor cost</CHED> <CHED H="1">Parts cost</CHED> <ENT I="01">Replace all affected floor beam side-of-body fittings and inspect for damage</ENT> <ENT>527 work-hours × $85 per hour = $44,795</ENT> <ENT>$218,250</ENT> <ENT>$263,045</ENT> </ROW> </GPOTABLE> The FAA estimates the following costs to do any replacements that would be required based on the results of the proposed inspection. The agency has no way of determining the number of aircraft that might need this replacement: <GPOTABLE COLS="4" OPTS="L2,i1" CDEF="s50,r50,12C,12C"> <TTITLE>On-Condition Costs for Option 1</TTITLE> <CHED H="1">Action</CHED> <CHED H="1">Labor cost</CHED> <CHED H="1">Parts cost</CHED> <ENT I="01">Replace floor beam side-of-body fitting and inspect for damage (per fitting)</ENT> <ENT>18 work-hours × $85 per hour = $1,530</ENT> <ENT>$8,730</ENT> <ENT>$10,260</ENT> </ROW> </GPOTABLE> The extent of damage found during the inspection done when the fittings are replaced could vary significantly from airplane to airplane. The FAA has no way of ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 19k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━