AD 97-01-08

This amendment adopts a new airworthiness directive (AD), applicable to certain Fokker Model F27 Mark 100, 200, 300, 400, 500, 600, and 700 series airplanes, that requires a one-time visual inspection to detect missing rivet heads or loose rivets of the applicable stringer-to-rib connections in the upper and lower wing skin, and repair, if necessary. In lieu of the one-time visual inspection or in addition to that inspection, the AD also requires replacement of certain rivets with certain new rivets in all applicable rib-to-stringer connections of the upper and lower wings. This amendment is prompted by reports of missing rivet heads at the rib-to-stringer connections of the upper and lower wing skin at stringers 5 and 6. The actions specified by this AD are intended to prevent reduced structural integrity of the wings that is caused by problems associated with missing and/or loose rivets.

Final rule

97-01-08 FOKKER: Amendment 39-9879. Docket 96-NM-28-AD.
Applicability: Model F27 Mark 100, 200, 300, 400, 500, 600, and 700 series airplanes, serial numbers 10653 through 10692 inclusive; on which Part 1 of the Accomplishment Instructions of Fokker Service Bulletins F27/57-68 and F27/57-70 has not been accomplished; 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 prevent loose or missing rivets at the rib-to-stringer connections of the upper and lower wing skin at stringers 5 and 6, which could result in reduced structural integrity of the wings; accomplish the following:

(a) Except as provided by paragraph (c) of this AD: Prior to the accumulation of 10,000 total flight cycles, or within 2 months after the effective date of this AD, whichever occurs later, perform a one-time visual inspection to detect missing rivet heads or loose rivets of the applicable stringer-to-rib connections in the upper and lower skin, in accordance with Part 2 of the Accomplishment Instructions of Fokker Service Bulletin F27/57-74, dated November 15, 1994.

(1) If no missing rivet head and no loose rivet is detected, no further action is required by paragraph (a) of this AD.

(2) If any missing rivet head or loose rivet is detected, prior to further flight, repair the affected rib-to-stringer connection, in accordance with Part 1 of the Accomplishment Instructions of the service bulletin.

(b) Prior to the accumulation of 10,000 total flight cycles, or within 1 year after the effective date of this AD, whichever occurs later, replace rivets having part number (P/N) MS20600AD4W2 with new rivets having P/N CR3553P4 in all applicable rib-to-stringer connections of the upper and lower wings, in accordance with Part 1 of the Accomplishment Instructions of Fokker Service Bulletin F27/57-74, dated November 15, 1994.

(c) Airplanes on which the replacement required by paragraph (b) of this AD is performed within the compliance time specified in paragraph (a) of this AD are not required to accomplish the inspection required by paragraph (a) of this AD.

(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, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Standardization Branch, ANM-113.

NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Standardization Branch, ANM-113.

(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.

(f) The inspection, repair, and replacement shall be done in accordance with Fokker Service Bulletin F27/57-74, dated November 15, 1994. 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 Aircraft USA, Inc., 1199 North Fairfax Street, Alexandria, Virginia 22314. 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.

(g) This amendment becomes effective on February 13, 1997.

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 F27 Mark 100, 200, 300, 400, 500, 600, and 700 series airplanes was published in the Federal Register on July 24, 1996 (61 FR 38407). That action proposed to require a one-time visual inspection to detect missing rivet heads or loose rivets of the applicable stringer-to-rib connections in the upper and lower skin, and repair, if necessary. In lieu of the one-time visual inspection, or in addition to that inspection, that action also proposed to require replacement of certain rivets with certain new rivets in all applicable rib-to-stringer connections of the upper and lower wings.

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 Proposal
One commenter supports the proposed rule.

Request to Cite the Latest Dutch AD
One commenter notes that the preamble to the notice stated that "the RLD classified [Fokker Service Bulletin F27/57-74, dated November 15, 1994] as mandatory and issued Dutch airworthiness directive BLA 93-094 (A), dated July 16, 1993 . . . ." The commenter points out that the reference to BLA 93-094 (A) is incorrect, since that BLA 93-094 (A) was issued in 1993, a year earlier than the release of Fokker Service Bulletin F27/57-74. The commenter states that the Dutch BLA that mandated that service bulletin is BLA 94-148, dated November 24, 1994.

The FAA concurs. The FAA inadvertently referenced the wrong BLA number and issue date in the preamble to the notice; it should have referenced BLA 94-148 as the applicable Dutch airworthiness directive. However, since that information is not restated in this final rule, no specific change is necessary.

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
The FAA estimates that 6 Fokker Model 100, 200, 300, 400, 500, 600, and 700 series airplanes of U.S. registry will be affected by this AD.

The required inspection will take approximately 4 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the required inspection action on U.S. operators is estimated to be $240 per airplane.

The required replacement will take approximately 19 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. The cost of required parts will be nominal. Based on these figures, the cost impact of the required replacement on U.S. operators is estimated to be $1,140 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: