AD 98-13-32

This amendment adopts a new airworthiness directive (AD), applicable to certain Fokker Model F.28 Mark 0100 series airplanes, that requires interim inspections to detect discrepancies of the main fitting subassembly of the main landing gear, and follow-on corrective actions, if necessary. This amendment also requires a one-time inspection to detect discrepancies of the fitting, repair of the fitting, if necessary, and application of new surface protection on the fitting, which would terminate the interim inspections. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent cracking of the main fitting subassembly of the main landing gear, which could result in collapse of the main landing gear.

Final rule

98-13-32 FOKKER: Amendment 39-10623. Docket 97-NM-329-AD.

Applicability: Model F.28 Mark 0100 series airplanes, equipped with Messier-Dowty main landing gear units having the part numbers and serial numbers specified in Messier-Dowty Service Bulletin F100-32-86, Revision 2, dated July 3, 1997, including Appendix A, Revision 1, dated November 1, 1996, and Appendix B, Revision 1, dated November 1, 1996; certificated in any category.

NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (c) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required as indicated, unless accomplished previously.

To prevent cracking of the main fitting subassembly of the main landing gear, which could result in collapse of the main landing gear, accomplish the following:

(a) Within 60 days after the effective date of this AD, perform a visual and an eddy current inspection to detect discrepancies (paint damage, corrosion or cracking) of the main fitting subassembly of the main landing gear, in accordance with Appendix B, Revision 1, dated November 1, 1996, of Messier-Dowty Service Bulletin F100-32-86, Revision 2, dated July 3, 1997.

(1) If no discrepancy is detected, or if any discrepancy is detected that is within the limits specified in Appendix B of the service bulletin: Repeat the inspections required by paragraph (a) ofthis AD thereafter at intervals not to exceed 60 days.

(2) If any discrepancy is detected that is outside the limits specified in Appendix B of the service bulletin: Prior to further flight, accomplish the requirements of paragraph (b) of this AD.

(b) Within 6 months after the effective date of this AD, perform a one-time eddy current inspection and a one-time visual inspection to detect discrepancies (paint damage, corrosion, or cracking) of the main fitting subassembly of the main landing gear, in accordance with the Accomplishment Instructions of Messier-Dowty Service Bulletin F100-32-86, Revision 2, dated July 3, 1997, including Appendix A, Revision 1, dated November 1, 1996, and Appendix B, Revision 1, dated November 1, 1996. Accomplishment of the actions required by this paragraph constitutes terminating action for the requirements of this AD.

(1) If no discrepancy is detected, prior to further flight, apply a protective treatment to the main fittings in accordance with the service bulletin.

(2) If any discrepancy is detected that can be repaired within the limits specified in the service bulletin, prior to further flight, repair the discrepancy, and apply a protective treatment to the main fittings, in accordance with the service bulletin.

(3) If any discrepancy is detected that cannot be repaired within the limits specified in the service bulletin, prior to further flight, repair in accordance with a method approved by the Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate.

NOTE 2: Accomplishment of the terminating actions required by paragraph (b) of this AD in accordance with Messier-Dowty Service Bulletin F100-32-86, including Appendix A and Appendix B; all Revision 1, all dated November 1, 1996; prior to the effective date of this AD, is acceptable for compliance with the requirements of this paragraph.

(c) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, International Branch, ANM-116. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, International Branch, ANM-116.

NOTE 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the International Branch, ANM-116.

(d) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.

(e) Except as provided by paragraph (b)(3) of this AD, the actions shall be done in accordance with Messier-Dowty Service Bulletin F100-32-86, Revision 2, dated July 3, 1997, including Appendix A, Revision 1, dated November 1, 1996, and Appendix B, Revision 1, dated November 1, 1996, which contains the following list of effective pages:

Page Number
Revision Level
Shown on Page
Date
Shown on Page
1, 5, 6
2
July 3, 1997
2-4, 7-17
1
November 1, 1996

APPENDIX A
1-3
1
November 1, 1996

APPENDIX B
1-5
1
November 1, 1996

This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Fokker Services B.V., Technical Support Department, P.O. Box 75047, 1117 ZN Schiphol Airport, the Netherlands; or from Messier-Dowty Ltd., Cage: K0654, Cheltenham Road, Gloucester, GL2 9QH, England. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

NOTE 4: The subject of this AD is addressed in Dutch airworthiness directive 1996-133/2(A), dated January 31, 1997.

(f) This amendment becomes effective on July 30, 1998.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to certain Fokker Model F.28 Mark 0100 series airplanes was published in the Federal Register on April 2, 1998 (63 FR 16165). That action proposed to require interim inspections to detect discrepancies of the main fitting subassembly of the main landing gear, and follow-on corrective actions, if necessary. That action also proposed to require a one-time inspection to detect discrepancies of the fitting, repair of the fitting, if necessary, and application of new surface protection on the fitting. Accomplishment of these actions would terminate the interim inspections.

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

Request to Cite Earlier Revision of Service Information
Onecommenter requests that provisions be added to allow accomplishment of inspection and rework required by paragraph (b) of the proposed AD in accordance with Revision 1 of Messier-Dowty Service Bulletin F100-32-86 in addition to Revision 2, as proposed in the NPRM. The FAA concurs. Since Revision 2 of the service bulletin contains no substantive differences from Revision 1, the FAA has determined that the actions required by paragraph (b) of this AD may be accomplished in accordance with Messier-Dowty Service Bulletin F100-32-86, including Appendix A and Appendix B; all Revision 1, all dated November 1, 1996. A "NOTE" has been added to the final rule to give credit to operators who may have previously accomplished the required actions in accordance with the earlier revision of the service bulletin.

Explanation of Changes Made to Proposal
In the proposal, the FAA inadvertently omitted references to Appendices A and B, both Revision 1, both dated November 1, 1996, of Messier-Dowty Service Bulletin F100-32-86, Revision 2, dated July 3, 1997. Therefore, the FAA has revised the final rule accordingly.

Conclusion
After careful review of the available data, including the comment 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
The FAA estimates that 127 airplanes of U.S. registry will be affected by this AD.

It will take approximately 2 work hours per airplane to accomplish the required interim inspections. Based on an average labor rate of $60 per work hour, the cost impact of the required interim inspections on U.S. operators is estimated to be $15,240, or $120 per airplane, per inspection cycle.

It will take approximately 14 work hours per airplane to accomplish the required terminating actions. Based on an average labor rate of $60 per work hour the cost impact of the required terminating actions on U.S. operators is estimated to be $106,680, or $840 per airplane.

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.

Regulatory Impact
The regulations adopted herein will not have substantial direct effects 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, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

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.

39.13 [Amended]
2. Section 39.13 is amended by adding the following new airworthiness directive: