- Effective
- April 16, 2008
- Published
- March 12, 2008 · 73 FR 13109–13111
- Issued
- February 28, 2008
- Model
- 737-200 Series
- Data sheet
- TCDSA16WE
- Registered aircraft
- 6 matched by model
- Product
- Aircraft · Large airplane
- Amendment
- 39-15421
- Docket
- FAA-2007-0228
- Project
- 2007-NM-107-AD
- Issued as
- Final rule
Unofficial copy from the Federal Register XML, document E8-4674. 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 | 157 KB | 1c022ee7…ec5651f | E8-4674.pdf on govinfo.gov |
| Federal Register XML | 18 KB | e53e13fc…8d18d3e | E8-4674.xml on federalregister.gov |
| FAA DRS HTML attachment | 53 KB | ec7ed261…4a7f9df | FAA DRS (API key needed) |
| FAA DRS PDF | 27 KB | af1707e5…d6b6a38 | FAA DRS (API key needed) |
On this page
Summary
We are adopting a new airworthiness directive (AD) for certain Boeing Model 737-200 series airplanes. This AD requires repetitive inspections to detect cracking of the support fittings of the Krueger flap actuators, and corrective actions if necessary. This AD also requires eventual replacement of any existing aluminum support fitting on each wing with a steel fitting, and modification of the aft attachment of the actuator. Doing these actions terminates the repetitive inspection requirements. This AD results from reports of cracking due to fatigue and stress corrosion of the support fittings of the Krueger flap actuator. We are issuing this AD to prevent cracking of the support fittings, which could result in fracturing of the actuator attach lugs, separation of the actuator from the support fitting, severing of the hydraulic lines, resultant loss of hydraulic fluids, and consequent reduced controllability of the airplane.
The airworthiness directive
2008-06-09 Boeing: Amendment 39-15421. Docket No. FAA-2007-0228; Directorate Identifier 2007-NM-107-AD.
(a) Effective Date
PDF page 2(a) This airworthiness directive (AD) is effective April 16, 2008.
(b) Affected ADs
PDF page 2(b) None.
(c) Applicability
PDF page 2(c) This AD applies to Boeing Model 737-200 series airplanes, line numbers 814 through 826 inclusive, certificated in any category.
(d) Unsafe Condition
PDF page 2(d) This AD results from reports of cracking due to fatigue and stress corrosion of the support fittings of the Krueger flap actuator. We are issuing this AD to prevent cracking of the support fittings, which could result in fracturing of the actuator attach lugs, separation of the actuator from the support fitting, severing of the hydraulic lines, resultant loss of hydraulic fluids, and consequent reduced controllability of the airplane.
(e) Compliance
PDF page 2(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
(f) Repetitive Inspections
PDF page 2(f) Within 12 months after the effective date of this AD, do a high frequency eddy current (HFEC) inspection to detect cracking of the support fittings of the Krueger flap actuator on each wing, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 737-57-1129, Revision 3, dated March 19, 2007.
(1) If no cracking is detected, repeat the inspection thereafter at intervals not to exceed 3,000 flight hours until the terminating action required by paragraph (g) of this AD is accomplished.
(2) If any cracking is detected, before further flight, do the replacement and modification specified in paragraph (g) of this AD.
(g) Terminating Action
PDF page 2(g) Within 60 months after the effective date of this AD: Replace any existing Krueger flap actuator aluminum support fitting on each wing with a steel fitting, and modify the actuator aft attachment, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 737-57-1129, Revision 3, dated March 19, 2007. Doing this replacement and modification terminates the repetitive inspection requirements of paragraph (f) of this AD.
(h) Parts Replacement
PDF page 2(h) As of the effective date of this AD, no person may install on any airplane any aluminum support fitting (actuator support assembly) identified in the “Existing Part Number” column of paragraph 2.C. of Boeing Special Attention Service Bulletin 737-57-1129, Revision 3, dated March 19, 2007.
(i) Actions Accomplished in Accordance With Previous Revisions of Service Bulletin
PDF page 2(i) Actions done before the effective date of this AD in accordance with the service bulletins listed in Table 1 of this AD, are acceptable for compliance with the corresponding requirements of this AD.
| Boeing service bulletin | Revision level | Date |
|---|---|---|
| 737-57-1129 | 1 | Oct. 30, 1981. |
| 737-57-1129 | 2 | May 28, 1998. |
(j) Alternative Methods of Compliance (AMOCs)
PDF page 2(j)(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.
(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 appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO.
(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 an Authorized Representative for the Boeing Commercial Airplanes Delegation Option Authorization Organization who 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.
(k) Material Incorporated by Reference
PDF page 3(k) You must use Boeing Special Attention Service Bulletin 737-57-1129, Revision 3, dated March 19, 2007, 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 this service information under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) For service information identified in this AD, contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207.
(3) You may review copies of the service information incorporated by reference at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, 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 April 16, 2008.
The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of April 16, 2008.
AddressesPage 1
For service information identified in this AD, contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207.
For further information contactPage 1
Nancy Marsh, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 917-6440; fax (425) 917-6590.
DiscussionPage 1
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an airworthiness directive (AD) that would apply to certain Boeing Model 737-200 series airplanes. That NPRM was published in the Federal Register on November 26, 2007 (72 FR 65909). That NPRM proposed to require repetitive inspections to detect cracking of the support fittings of the Krueger flap actuators, and corrective actions if necessary. The NPRM also proposed to require eventual replacement of any existing aluminum support fitting on each wing with a steel fitting, and modification of the aft attachment of the actuator. Doing these actions terminates the repetitive inspection requirements.
CommentsPage 1
We gave the public the opportunity to participate in developing this AD. We considered the one comment received. Boeing supports the NPRM.
ConclusionPage 1
We reviewed the relevant data, considered the comment received, and determined that air safety and the public interest require adopting the AD as proposed.
Costs of CompliancePage 1
There are about 13 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 |
|---|---|---|---|---|---|---|
| Inspection | 5 | $80 | $0 | $400, per inspection cycle | 3 | $1,200, per inspection cycle. |
| Replacement | 88 | 80 | 29,642 | $36,682 | 3 | $110,046. |
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
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), and
(3) 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.
You can find our regulatory evaluation and the estimated costs of compliance in the AD Docket.
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 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 · 6
Registered aircraft whose airframe or engine model this AD names. Matched by model only, so check each against the AD’s applicability.
| 1969 | 1 |
|---|---|
| 1979 | 1 |
| 1986 | 1 |
| 1987 | 1 |
2 with no year recorded