AD 2002-26-16

This amendment adopts a new airworthiness directive (AD), applicable to all Fokker Model F.28 Mark 0070 and 0100 series airplanes, that requires measurement of the over-center force of the thrust reverser operating levers, a functional test of the secondary lock solenoid of the thrust reversers, and corrective actions if necessary. The actions specified by this AD are intended to detect and correct an insufficient over-center force in the corresponding thrust reverser operating lever, and incorrect setting of the thrust reverser selector switch (S9), which could result in uncommanded deployment of the thrust reversers during flight and consequent reduced controllability of the airplane. This AD is intended to address the identified unsafe condition.

Final rule.

2002-26-16 Fokker Services B.V.: Amendment 39-13004. Docket 2001-NM-290-AD.

Applicability: All Model F.28 Mark 0070 and 0100 series airplanes, 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 (d) 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 detect and correct an insufficient over-center force in the corresponding thrust reverser operating lever, and incorrect setting of the thrust reverser selector switch (S9), which could result in uncommanded deployment of the thrust reversers during flight and consequent reduced controllability of the airplane, accomplish the following:

Over-Center Force Measurement and Readjustment

(a) Within 6 months after the effective date of this AD, measure the over-center force of the left- and right-hand thrust reverser operating levers, per paragraph 2.A. of the Accomplishment Instructions of Fokker Service Bulletin SBF100-76-015, dated January 15, 2001, including Service Bulletin Change Notification (SBCN) SBF100-76-015/01, dated May 1, 2001, and Manual Change Notification-Maintenance Document (MCNM) F100-060, Revision 1, dated March 19, 2001.

(1) If the over-center force is equal to or higher than 4.5 pounds, but not higher than 5.5 pounds, no further action is required by this paragraph.

(2) If the over-center force is less than 4.5 pounds or higher than 5.5 pounds, before further flight, readjust the over-center force and accomplish the corrective actions (including measuring and readjusting the minimum stop of the reverse-thrust lever and over-center force of the thrust reverser), per the service bulletin.

Functional Test and Corrective Actions

(b) Within 6 months after the effective date of this AD, perform a functional test of the secondary lock solenoid of the left- and right-hand thrust levers, per paragraph 2.B. of the Accomplishment Instructions of Fokker Service Bulletin SBF100-76-015, dated January 15, 2001, including SBCN SBF100-76-015/01, dated May 1, 2001, and MCNM F100-060, Revision 1, dated March 19, 2001.

(1) If the secondary lock solenoid does NOT (momentarily or continuously) energize with movement of the thrust levers as described in paragraph 2.B.(9) of the service bulletin, no further action is required by this paragraph.(2) If the secondary lock solenoid (momentarily or continuously) energizes with movement of the thrust levers as described in paragraph 2.B.(9) of the service bulletin, before further flight, perform a rigging check of the thrust reverser switchbox and repeat the functional test of the secondary lock solenoid, per paragraph 2.B.(9) of the service bulletin.

(i) If the solenoid does NOT (momentarily or continuously) energize with movement of the thrust levers as described in paragraph 2.B.(9) of the service bulletin, no further action is required by this paragraph.

(ii) If the secondary lock solenoid still (momentarily or continuously) energizes with movement of the thrust levers as described in paragraph 2.B.(9) of the service bulletin, before further flight, replace the thrust reverser switchbox with a new or serviceable switchbox, per the service bulletin.

Credit for Accomplishment per Prior Version of Service Information

(c) Accomplishment, before the effective date of this AD, of the actions specified in paragraphs (a) and (b) of this AD in accordance with Fokker Service Bulletin SBF100-76-015, dated January 15, 2001, including MCNM F100-060, dated January 1, 2001, is acceptable for compliance with the requirements of this AD.

Alternative Methods of Compliance

(d) 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, Transport Airplane Directorate, FAA. 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 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the International Branch, ANM-116.

Special Flight Permits

(e) 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.

Incorporation by Reference

(f) Unless otherwise specified in this AD, the actions shall be done in accordance with Fokker Service Bulletin SBF100-76-015, dated January 15, 2001, including Service Bulletin Change Notification SBF100-76-015/01, dated May 1, 2001, and Manual Change Notification MCNM F100-060, Revision 1, dated March 19, 2001. 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., P.O. Box 231, 2150 AE Nieuw-Vennep, the Netherlands. 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 3: Thesubject of this AD is addressed in Dutch airworthiness directive 2001-040, dated March 30, 2001.

Effective Date

(g) This amendment becomes effective on February 10, 2003.

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 all Fokker Model F.28 Mark 0070 and 0100 series airplanes was published in the Federal Register on April 5, 2002 (67 FR 16333). That action proposed to require measurement of the over-center force of the thrust reverser operating levers; a functional test to verify proper energizing of the secondary lock solenoid of the thrust reversers; and corrective actions, if necessary.

Explanation of Relevant Service Information

In the proposed AD, the FAA identified Fokker Service Bulletin SBF100-76-015, dated January 15, 2001, as the appropriate source of service information for the proposed requirements. Since the proposed AD was issued, Fokker issued Service Bulletin Change Notification (SBCN) SBF100-76-015/01, dated May 1, 2001, and Manual Change Notification-Maintenance Documentation (MCNM) F100-060, Revision 1,dated March 19, 2001. The revised MCNM provides wording that is consistent with the existing maintenance manual wording to clarify the procedures; the procedures otherwise remain unchanged. The SBCN advises that the MCNM changes have been incorporated into the service bulletin.

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.

Support for the Proposed AD

One commenter fully supports the proposed AD.

Request To Cite Revised Service Documents

The manufacturer requests that the proposed AD be revised to cite the most recent versions of the relevant service documents.

Based on a review of the document revisions, the FAA concurs with the request. Paragraphs (a) and (b) of this AD have been revised accordingly.

Request To Clarify Certain Requirements

The manufacturer requests that paragraph (b) of the proposed AD be revised for several reasons. First, the proposed language suggests that the functional test is intended to verify proper energizing of the secondary lock solenoid, whereas the solenoids are not supposed to energize during the test. Second, the reference to movement of the "thrust reverser operating lever" in paragraphs (b)(1), (b)(2), (b)(2)(i), and (b)(2)(ii) of the proposed AD suggests that the thrust reverser operating levers are operated during the functional test. The manufacturer advises that the thrust levers, not the thrust reverser operating levers, are operated during the functional test. Third, the manufacturer suggests that paragraph (b)(2) of the proposed AD, which would require operators to repeat the functional test "one more time," could be misinterpreted. The service bulletin provides instructions to perform the functional test at least five times before, and (if necessary) after, a rigging check of the thrust lever switchbox. The functional test involves "slamming" the thrust levers with the thrust reverser operating levers in the stowed position. The commenter suggests a reader could infer that a single "slam" is sufficient.

The FAA agrees with the requests for the reasons provided by the commenter and has made the following changes in this final rule: First, the phrase "to verify proper energizing" has been removed from the summary and paragraphs (b) and (b)(2) of this AD. Second, the phrase "movement of thrust reverser operating levers" has been changed to "movement of the thrust levers" in paragraphs (b)(1), (b)(2), (b)(2)(i), and (b)(2)(ii). Third, the phrase "one more time" has been removed from paragraph (b)(2).

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 increasethe scope of the AD.

Cost Impact

The FAA estimates that 139 airplanes of U.S. registry will be affected by this AD, that it will take approximately 2 work hours per airplane to accomplish the required actions, and that the average labor rate is $60 per work hour. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $16,680, or $120 per airplane.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the requirements of this AD, 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 in14 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: