Airworthiness Directives; Boeing Model 767 Series Airplanes Powered by General Electric or Pratt & Whitney Engines

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Final rule.

SUMMARY:

This amendment supersedes an existing airworthiness directive (AD), applicable to certain Boeing Model 767 series airplanes powered by General Electric or Pratt & Whitney engines, that currently requires repetitive inspections to detect discrepancies of the four aft-most fastener holes in the horizontal tangs of the midspar fitting of the strut, and corrective actions, if necessary. That AD also provides an optional terminating action for repetitive inspections. This amendment expands the area on which the inspections are required. The actions specified by this AD are intended to prevent fatigue cracking in the primary strut structure and reduced structural integrity of the strut, which could result in separation of the strut and engine. This action is intended to address the identified unsafe condition.

DATES:

Effective June 9, 2004.

The incorporation by reference of Boeing Service Bulletin 767-54A0101, Revision 3, dated September 5, 2002, as listed in the regulations, is approved by the Director of the Federal Register as of June 9, 2004.

The incorporation by reference of Boeing Service Bulletin 767-54A0101, Revision 1, dated February 3, 2000, as listed in the regulations, was approved previously by the Director of the Federal Register as of May 15, 2001 (66 FR 18523, April 10, 2001).

ADDRESSES:

The service information referenced in this AD may be obtained from Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207. This information may be examined at the Federal Aviation Administration (FAA), Transport Airplane Directorate, Rules Docket, 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.

FOR FURTHER INFORMATION CONTACT:

Suzanne Masterson, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington; telephone (425) 917-6441; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by superseding AD 2001-07-05, amendment 39-12170 (66 FR 18523, April 10, 2001), which is applicable to certain Boeing Model 767 series airplanes powered by General Electric or Pratt & Whitney engines, was published in the Federal Register on December 8, 2003 (68 FR 68308). The action proposed to continue to require repetitive inspections to detect discrepancies of the four aft-most fastener holes in the horizontal tangs of the midspar fitting of the strut, and corrective actions, if necessary. The action also proposed to continue to provide an optional terminating action for repetitive inspections. In addition, the action proposed expanding the area on which the inspections are required.

Comments

Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.

Concurs With the Proposed AD

One commenter concurs with the contents of the proposed AD.

Request To Clarify the Difference Between the Proposed AD and the Service Bulletin

One commenter requests clarification of the difference between the proposed AD and the service bulletin. The commenter's understanding of the intent of the “Difference Between Proposed Rule and Service Bulletin” paragraph of the proposed AD is that operators are allowed to inspect the four forward fastener holes not inspected per paragraph (a)(1), (a)(2), or (b) of the proposed AD at the next repetitive inspection specified in Table 1 of the proposed AD for all eight fastener holes. However, the commenter notes that paragraph (e) of the proposed AD requires, within 10,000 total flight cycles or 600 flight cycles after the effective date of this AD, whichever occurs later, inspection of all eight aft-most fastener holes or the four forward fastener holes not inspected per paragraph (a)(1), (a)(2), or (b) of the proposed AD. The commenter states that paragraph (e) appears to contradict the “Difference Between Proposed Rule and Service Bulletin” paragraph in that the compliance time of within 600 flight cycles specified by paragraph (e) would require the inspection of the four fastener holes not inspected per paragraph (a)(1), (a)(2), or (b) prior to the next repetitive inspection specified in Table 1 of the proposed AD.

The FAA agrees that clarification of the difference between the proposed AD and the service bulletin is necessary in the final rule. The commenter is correct in its understanding of paragraph (e) that the compliance time of within 600 flight cycles would require the inspection of the four fastener holes not inspected per paragraph (a)(1), (a)(2), or (b) prior to the next repetitive inspection specified in Table 1 of the proposed AD. Our intention in the “Difference Between Proposed Rule and Service Bulletin” paragraph was to allow operators to inspect the four forward fastener holes inspected per paragraph (a)(1), (a)(2), or (b) of the proposed AD at the next repetitive inspection specified in Table 1 of the proposed AD. In our explanation in that paragraph, we did not include the phrase “not inspected per paragraph (a)(1), (a)(2), or (b)” when we stated, “during the first detailed inspection, this proposed AD allows for the inspection of only four of the aft most fastener holes.” However, no change to the final rule is necessary in this regard, since the “Difference Between Proposed Rule and Service Bulletin” paragraph is not restated in the final rule.

Request To Revise Wording in Paragraph (f) of the Proposed AD

One commenter requests that the wording in paragraph (f) of the proposed AD be revised to “Perform the follow-on actions specified in paragraph (a)(1) or (a)(2) of this AD.” The commenter states that if no cracking or discrepancy is detected during the inspections required by paragraph (e) of the proposed AD, paragraph (f) requires operators to “Perform the follow-on actions specified in paragraph (a)(2)(i) or (a)(2)(ii) of this AD * * * and repeat the inspections of all eight aft-most fastener holes thereafter at the applicable intervals specified in Table 1 of this AD.” The commenter contends this implies that the detailed inspection required by paragraph (a)(1) of the proposed AD is not allowed as an option for repeat inspections. However, the commenter points out that Table 1 of the proposed AD implies that detail inspections are an option. Revising the wording to “Perform the follow-on actions specified in paragraph (a)(2)(i) or (a)(2)(ii) of this AD” would allow either detailed inspections or high frequency eddy current (HFEC) inspections for the repeat inspections.

We agree with the commenter that paragraph (f) needs to be revised. Either detailed inspections or HFEC inspections are allowed for the repeat inspections. However, we do not agree with the wording suggested by the commenter. Follow-on actions specified in paragraphs (a)(2)(i) and (a)(2)(ii), as applicable, are required if operators did the HFEC inspections required by paragraph (a)(2). There are no follow-on actions if operators did the detailed inspection required by paragraph (a)(1). Repeat inspections are required for operators that did either the detailed inspection or the HFEC inspections. We have revised paragraph (f) of the final rule and added paragraph (g) to the final rule to clarify this issue. Also, we have revised the paragraph numbering for the remainder of the final rule accordingly.

Request To Allow an Alternate Sealant

One commenter requests that part number (P/N) RTV108 be allowed as an alternate sealant to P/N BMS 5-95 for actions required by paragraph (d) of the proposed AD. The commenter did not submit justification for this request. The commenter did refer to Boeing's concurrence with this substitution via a telex but the telex was not submitted.

We do not agree with the request to allow P/N RTV108 as an alternate sealant. However, under the provisions of paragraph (k) of the final rule, we may consider requests for approval of an alternative method of compliance if sufficient data are submitted to substantiate that such a design change would provide an acceptable level of safety.

Clarification of Corrective Action Requirements

The corrective actions specified in paragraph (h) of the proposed AD are to be accomplished “if any cracking or discrepancy is detected during any inspection required by paragraph (e) of this AD.” Since paragraphs (f) and (g) of the final rule require the repetitive inspections specified in paragraph (e), we determined that adding paragraphs (f) and (g) to paragraph (h) of the final rule would clarify the corrective action requirements. Accordingly, we have revised paragraph (h) of the final rule: “If any cracking or discrepancy is detected during any inspection required by paragraphs (e), (f), or (g) of this AD * * *”

Conclusion

After careful review of the available data, including the comments noted above, the FAA has determined that air safety and the public interest require the adoption of the rule with the changes previously described. The FAA has determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.

Cost Impact

There are approximately 625 airplanes of the affected design in the worldwide fleet. The FAA estimates that 263 airplanes of U.S. registry will be affected by this AD.

The detailed inspection that is required in this AD action will take approximately 1 work hour per airplane to accomplish, at an average labor rate of $65 per work hour. Based on these figures, the cost impact of the required inspection on U.S. operators is estimated to be $17,095, or $65 per airplane, per inspection cycle.

The eddy current inspection that is required by the AD action will take approximately 3 work hours per airplane to accomplish, at an average labor rate of $65 per work hour. Based on these figures, the cost impact of the required inspection on U.S. operators is estimated to be $51,285, or $195 per airplane, per inspection cycle.

The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions.

Regulatory Impact

The regulations adopted herein 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. Therefore, it is determined that this final rule does not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this action (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. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

Adoption of the Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39—AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

2. Section 39.13 is amended by removing amendment 39-12170 ( 66 FR 18523, April 10, 2001), and by adding a new airworthiness directive (AD), amendment 39-13603, to read as follows:

2004-09-14 Boeing: Amendment 39-13603. Docket 2002-NM-275-AD. Supersedes AD 2001-07-05, Amendment 39-12170.

Applicability: Model 767 series airplanes, as listed in Boeing Service Bulletin 767-54A0101, Revision 3, dated September 5, 2002; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent fatigue cracking in the primary strut structure and reduced structural integrity of the strut, which could result in separation of the strut and engine, accomplish the following:

Requirements of AD 2001-07-05

Repetitive Inspections

(a) Except as provided by paragraph (b) of this AD, before the accumulation of 10,000 total flight cycles, or within 600 flight cycles after May 15, 2001 (the effective date of AD 2001-07-05, amendment 39-12170 (66 FR 18523, April 10, 2001), whichever occurs later: Accomplish the inspections required by paragraph (a)(1) or (a)(2) of this AD, as applicable.

(1) Perform a detailed inspection of the four aft-most fastener holes in the horizontal tangs of the midspar fitting of the strut to detect cracking, in accordance with Part 1, “Detailed Inspection,” of the Accomplishment Instructions of Boeing Service Bulletin 767-54A0101, Revision 1, dated February 3, 2000. If no cracking is detected, repeat the inspection thereafter at the applicable intervals specified in Table 1, “Reinspection Intervals for Part 1—Detailed Inspection” included in Figure 1 of the service bulletin.

Note 1:

For the purposes of this AD, a detailed inspection is defined as: “An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required.”

(2) Perform a high frequency eddy current inspection of the four aft-most fastener holes in the horizontal tangs of the midspar fitting of the strut to detect discrepancies (cracking, incorrect fastener hole diameter), in accordance with Part 2, “High Frequency Eddy Current (HFEC) Inspection,” of the Accomplishment Instructions of the service bulletin. Accomplish the requirements specified in paragraph (a)(2)(i) or (a)(2)(ii) of this AD, as applicable; and repeat the inspection thereafter at the applicable intervals specified in Table 2, “Reinspection Intervals for Part 2—HFEC Inspection” included in Figure 1 of the service bulletin.

(i) If no cracking is detected and the fastener hole diameter is less than or equal to 0.5322 inch, before further flight, rework the hole in accordance with Part 3 of the Accomplishment Instructions of the service bulletin.

(ii) If no cracking is detected and the fastener hole diameter is greater than 0.5322 inch, before further flight, accomplish the requirements specified in either paragraph (c)(1) or (c)(2) of this AD.

(b) For airplanes on which the two aft-most fasteners have been inspected in accordance with Boeing Service Bulletin 767-54A0101, Revision 1, dated February 3, 2000, prior to May 15, 2001: Perform the initial inspection of the four aft-most fasteners in accordance with paragraph (a) of this AD before the accumulation of 10,000 total flight cycles, or within 1,500 flight cycles after May 15, 2001, whichever occurs later.

Corrective Actions

(c) If any cracking is detected after accomplishment of any inspection required by paragraph (a) of this AD, before further flight, accomplish the requirements specified in either paragraph (c)(1) or (c)(2) of this AD.

(1) Accomplish the terminating action specified in Part 4 of the Accomplishment Instructions of Boeing Service Bulletin 767-54A0101, Revision 1, dated February 3, 2000; or Boeing Service Bulletin 767-54A0101, Revision 3, dated September 5, 2002. Accomplishment of this paragraph terminates the requirements of this AD.

(2) Replace the midspar fitting of the strut with a serviceable part, or repair in accordance with a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA. Repeat the applicable inspection thereafter at the applicable time specified in paragraph (a)(1) or (a)(2) of this AD.

(d) If any discrepancies (cracking, incorrect fastener hole diameter) are detected during any inspection required by paragraph (a) of this AD, for which the service bulletin specifies that the manufacturer may be contacted for disposition of those repair conditions: Before further flight, accomplish the corrective actions (including fastener hole rework and/or midspar fitting replacement) in accordance with a method approved by the Manager, Seattle ACO; or in accordance with data meeting the type certification basis of the airplane approved by a Boeing Company Designated Engineering Representative who has been authorized by the Manager, Seattle ACO, to make such findings. For a method to be approved by the Manager, Seattle ACO, as required by this paragraph, the Manager's approval letter must specifically reference this AD.

New Requirements of This AD

Additional Inspections

(e) Prior to the accumulation of 10,000 total flight cycles, or within 600 flight cycles after the effective date of this AD, whichever occurs later: Perform the inspections specified in paragraph (a)(1) or (a)(2) of this AD, as applicable, on all eight aft-most fastener holes or the four forward fastener holes in the group of eight aft-most fastener holes not inspected per paragraph (a)(1), (a)(2), or (b) of this AD. The inspection must be done per the Accomplishment Instructions in Boeing Service Bulletin 767-54A0101, Revision 3, dated September 5, 2002. Accomplishment of the applicable inspection on all eight aft-most fastener holes constitutes terminating action for the repetitive inspection requirements of paragraphs (a)(1), (a)(2), and (b) of this AD.

(f) If no cracking or discrepancy is detected during any detailed inspection required by paragraph (e) of this AD, repeat the inspections of all eight aft-most fastener holes thereafter at the applicable intervals specified in Table 1 of this AD.

(g) If no cracking or discrepancy is detected during any HFEC inspection required by paragraph (e) of this AD: Perform the follow-on actions specified in paragraph (a)(2)(i) or (a)(2)(ii) of this AD, as applicable, per the Accomplishment Instructions in Boeing Service Bulletin 767-54A0101, Revision 3, dated September 5, 2002; and repeat the inspections of all eight aft-most fastener holes thereafter at the applicable intervals specified in Table 1 of this AD.

Corrective Actions

(h) If any cracking or discrepancy is detected during any inspection required by paragraphs (e), (f), or (g) of this AD, before further flight: Accomplish the corrective actions described in paragraph (c) of this AD, per the Accomplishment Instructions in Boeing Service Bulletin 767-54A0101, Revision 3, dated September 5, 2002, except as provided in paragraph (d) of this AD.

Service Bulletin Revisions

(i) Accomplishment of the terminating action in paragraph (c)(1) of this AD, per the original release of Boeing Service Bulletin 767-54A0101, dated September 23, 1999; or Revision 2 of Boeing Service Bulletin 767-54A0101, dated January 10, 2002; is acceptable for compliance with the requirements of this AD. As of the effective date of this AD, only Revision 3 of Boeing Service Bulletin 767-54A0101, dated September 5, 2002, may be used for accomplishment of the terminating action in paragraph (c)(1) of this AD.

Inspections Accomplished Per Previous Issue of Service Bulletin

(j) Inspections required by paragraphs (a) and (b) of this AD that are accomplished before the effective date of this AD per Revision 2 of Boeing Service Bulletin 767-54A0101, dated January 10, 2002; or Revision 3 of Boeing Service Bulletin 767-54A0101, dated September 5, 2002; are considered acceptable for compliance with the corresponding action specified in this AD.

Alternative Methods of Compliance

(k) In accordance with 14 CFR 39.19, the Manager, Seattle ACO, FAA, is authorized to approve alternative methods of compliance (AMOCs) for this AD.

Incorporation by Reference

(l) Unless otherwise specified in this AD, the actions shall be done in accordance with Boeing Service Bulletin 767-54A0101, Revision 1, dated February 3, 2000; and Boeing Service Bulletin 767-54A0101, Revision 3, dated September 5, 2002; as applicable.

(1) The incorporation by reference of Boeing Service Bulletin 767-54A0101, Revision 3, dated September 5, 2002, is approved by the Director of the Federal Register, in accordance with 5 U.S.C. 552(a) and 1 CFR part 51.

(2) The incorporation by reference of Boeing Service Bulletin 767-54A0101, Revision 1, dated February 3, 2000, was approved previously by the Director of the Federal Register as of May 15, 2001 (66 FR 18523, April 10, 2001).

(3) Copies may be obtained from Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be inspected 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.

Effective Date

(m) This amendment becomes effective on June 9, 2004.