- Effective
- February 9, 2011
- Published
- January 5, 2011 · 76 FR 426–428
- Issued
- December 22, 2010
- Supersedes
- AD2008-21-03
- Models
- 737-300 Series, 737-400 Series, 737-500 Series
- Data sheet
- TCDSA16WE
- Registered aircraft
- 42 matched by model
- Product
- Aircraft · Large airplane
- ATA chapter
- 54 · Nacelles and pylons
- Amendment
- 39-16566
- Docket
- FAA-2010-0855
- Project
- 2010-NM-066-AD
- Issued as
- Final rule
Unofficial copy from the Federal Register XML, document 2010-33003. Only the govinfo PDF is the legal edition. DRS record last changed May 30, 2024.
Copies of the files this page was built from, with their SHA-256. Retrieved October 18, 2026.
| File | Size | SHA-256 | Original |
|---|---|---|---|
| Official PDF | 159 KB | 507f3052…44585a5 | 2010-33003.pdf on govinfo.gov |
| Federal Register XML | 21 KB | a558a3ab…675fdef | 2010-33003.xml on federalregister.gov |
| FAA DRS HTML attachment | 60 KB | c37b9b8c…6a6f0bd | FAA DRS (API key needed) |
| FAA DRS PDF | 44 KB | 085e975c…5930bd6 | FAA DRS (API key needed) |
On this page
Summary
We are superseding an existing airworthiness directive (AD) for the products listed above. That AD currently requires repetitive inspections for discrepancies of the fuse pins of the inboard and outboard midspar fittings of the nacelle strut, and corrective actions if necessary. This new AD requires replacing the midspar fuse pins with new, improved fuse pins, which would terminate the repetitive inspections. This AD was prompted by a report of corrosion damage of the chrome runout on the head side found on all four midspar fuse pins of the nacelle strut. Additionally, a large portion of the chrome plate was missing from the corroded area of the shank. We are issuing this AD to prevent damage of the fuse pins of the inboard and outboard midspar fittings of the nacelle strut, which could result in reduced structural integrity of the fuse pins, and consequent loss of the strut and separation of the engine from the airplane.
The airworthiness directive
2011-01-12 The Boeing Company: Amendment 39-16566; Docket No. FAA-2010-0855; Directorate Identifier 2010-NM-066-AD.
(a) Effective Date
PDF page 2(a) This airworthiness directive (AD) is effective February 9, 2011.
(b) Affected ADs
PDF page 2(b) This AD supersedes AD 2008-21-03, Amendment 39-15687.
(c) Applicability
PDF page 2(c) This AD applies to all The Boeing Company Model 737-300, -400, and -500 series airplanes, certificated in any category.
(d) Subject
PDF page 2(d) Air Transport Association (ATA) of America Code 54: Nacelles/Pylons.
(e) Unsafe Condition
PDF page 2(e) This AD results from a report of corrosion damage of the chrome runout on the head side found on all four midspar fuse pins of the nacelle strut. Additionally, a large portion of the chrome plate was missing from the corroded area of the shank. The Federal Aviation Administration is issuing this AD to prevent damage of the fuse pins of the inboard and outboard midspar fittings of the nacelle strut, which could result in reduced structural integrity of the fuse pins, and consequent loss of the strut and separation of the engine from the airplane.
(f) Compliance
PDF page 2(f) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
(g) Repetitive Inspections/Corrective Actions, With Revised Service Information
PDF page 2(g) At the applicable time specified in paragraph 1.E., “Compliance” of Boeing Special Attention Service Bulletin 737-54-1044, dated December 10, 2007; except, where that service bulletin specifies a compliance time after the date on that service bulletin, this AD requires compliance within the specified compliance time after November 13, 2008 (the effective date of AD 2008-21-03): Do a detailed inspection for discrepancies of the fuse pins of the inboard and outboard midspar fittings of the nacelle strut by doing all the actions, including all applicable corrective actions, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 737-54-1044, dated December 10, 2007; or Boeing Alert Service Bulletin 737-54A1044, Revision 2, dated January 20, 2010. Do all applicable corrective actions before further flight. Repeat the inspection at the time specified in paragraph 1.E. of Boeing Special Attention Service Bulletin 737-54-1044, dated December 10, 2007. Accomplishing the actions of paragraph (h) of this AD terminates the requirements of this paragraph.
(h) Replacement
PDF page 3(h) Within 120 months after the effective date of this AD, replace all midspar fuse pins having part number (P/N) 311A1092-2 with a midspar fuse pin having P/N 311A1092-3, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 737-54A1044, Revision 2, dated January 20, 2010. Accomplishing the requirements of this paragraph terminates the requirements of paragraph (g) of this AD for that fuse pin.
(i) Actions Accomplished According to Previous Revision of Service Information
PDF page 3(i) Actions done before the effective date of this AD in accordance with Boeing Special Attention Service Bulletin 737-54-1044, Revision 1, dated November 26, 2008, are acceptable for compliance with the corresponding requirements of this AD.
(j) Alternative Methods of Compliance (AMOCs)
PDF page 3(j)(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Alan Pohl, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 917-6450; fax (425) 917-6590. Information may be e-mailed to: 9- ANM-Seattle-ACO-AMOC-Requests@faa.gov.
(2) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your principal maintenance inspector (PMI) or principal avionics inspector (PAI), as appropriate, or lacking a principal inspector, your local Flight Standards District Office. The AMOC approval letter must specifically reference this AD.
(3) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD if it is approved by the Boeing Commercial Airplanes Organization Designation Authorization (ODA) that has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD.
(4) AMOCs approved in accordance with the requirements of AD 2008-21-03 are acceptable for the corresponding requirements of this AD.
(k) Related Information
PDF page 3(k) For more information about this AD, contact Alan Pohl, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 917-6450; fax (425) 917-6590; e-mail: alan.pohl@faa.gov.
(l) Material Incorporated by Reference
PDF page 3(l) You must use Boeing Special Attention Service Bulletin 737-54-1044, dated December 10, 2007; or Boeing Alert Service Bulletin 737-54A1044, Revision 2, dated January 20, 2010; as applicable; to do the actions required by this AD, unless the AD specifies otherwise.
(1) The Director of the Federal Register approved the incorporation by reference of Boeing Alert Service Bulletin 737-54A1044, Revision 2, dated January 20, 2010, under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) The Director of the Federal Register previously approved the incorporation by reference of Boeing Special Attention Service Bulletin 737-54-1044, dated December 10, 2007, on November 13, 2008 (73 FR 59493, October 9, 2008).
(3) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone 206-544-5000, extension 1; fax 206-766-5680; e-mail me.boecom@boeing.com; Internet https://www.myboeingfleet.com.
(4) You may review copies of the service information at the FAA, 1601 Lind Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221.
(5) You may also review copies of the service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at an NARA facility, call 202-741-6030, or go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.
Rule preamble
The FAA’s background, reasoning and cost estimate, published with the AD.
DatesPage 1
This AD is effective February 9, 2011.
The Director of the Federal Register approved the incorporation by reference of a certain publication listed in the AD as of February 9, 2011.
The Director of the Federal Register approved the incorporation by reference of a certain other publication listed in this AD as of November 13, 2008 (73 FR 59493, October 9, 2008).
AddressesPage 1
For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone 206-544-5000, extension 1; fax 206-766-5680; e-mail me.boecom@boeing.com; Internet https://www.myboeingfleet.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221.
For further information contactPage 1
Alan Pohl, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 917-6450; fax (425) 917-6590; e-mail: alan.pohl@faa.gov.
DiscussionPage 1
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede airworthiness directive (AD) 2008-21-03, Amendment 39-15687 (73 FR 59493, October 9, 2008). That AD applies to the specified products. The NPRM published in the Federal Register on September 23, 2010 (75 FR 57882). That NPRM proposed to continue to require repetitive inspections for discrepancies of the fuse pins of the inboard and outboard midspar fittings of the nacelle strut, and corrective actions if necessary. That NPRM also proposed to require replacing the midspar fuse pins with new, improved fuse pins, which would terminate the requirement for repetitive detailed inspections.
CommentsPage 2
We gave the public the opportunity to participate in developing this AD. We have considered the comment received. Boeing supports the NPRM.
ConclusionPage 2
We reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting the AD as proposed.
Costs of CompliancePage 2
There are about 1,961 airplanes of the affected design in the worldwide fleet. The following table provides the estimated costs for U.S. operators to comply with this AD.
| Action | Work hours | Average labor rate per hour | Parts | Cost per airplane | Number of U.S.- registered airplanes | Fleet cost |
|---|---|---|---|---|---|---|
| Repetitive detailed inspections (required by AD 2008-21-03) | 4 | $85 | None | $340, per inspection cycle | 616 | $209,440, per inspection cycle. |
| Midspar fuse pin replacement (new action) | 1 per pin (up to 4 pins per airplane) | 85 | $843 per pin | Up to $3,712 | 616 | Up to $2,286,592. |
Authority for This RulemakingPage 2
Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.
We are issuing this rulemaking under the authority described in subtitle VII, part A, subpart III, section 44701, “General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.
Regulatory findingsPage 2
We have determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.
For the reasons discussed above, I certify that this AD:
(1) Is not a “significant regulatory action” under Executive Order 12866,
(2) Is not a “significant rule” under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979),
(3) Will not affect intrastate aviation in Alaska, and
(4) Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.
Adoption of the amendmentPage 2
Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:
1. The authority citation for part 39 continues to read as follows:
2. The FAA amends § 39.13 by removing airworthiness directive (AD) 2008-21-03, Amendment 39-15687 (73 FR 59493, October 9, 2008), and adding the following new AD:
Affected TCDS · 1
The type certificate data sheets for the models this AD names, matched by model and maker.
Registered aircraft · 42
Registered aircraft whose airframe or engine model this AD names. Matched by model only, so check each against the AD’s applicability.
| 1986 | 2 |
|---|---|
| 1987 | 3 |
| 1989 | 2 |
| 1990 | 1 |
| 1991 | 5 |
| 1992 | 4 |
| 1993 | 4 |
| 1994 | 1 |
| 1995 | 3 |
| 1997 | 2 |
| 1998 | 2 |
| 1999 | 1 |
12 with no year recorded