[Federal Register Volume 61, Number 143 (Wednesday, July 24, 1996)] [Proposed Rules] [Pages 38407-38409] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 96-18773] ======================================================================= ----------------------------------------------------------------------- DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. 96-NM-28-AD] RIN 2120-AA64 Airworthiness Directives; Fokker Model F27 Mark 100, 200, 300, 400, 500, 600, and 700 Series Airplanes AGENCY: Federal Aviation Administration, DOT. ACTION: Notice of proposed rulemaking (NPRM). ----------------------------------------------------------------------- SUMMARY: This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Fokker Model F27 Mark 100, 200, 300, 400, 500, 600, and 700 series airplanes. This proposal would 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 wing skin, and repair, if necessary. In lieu of the one-time visual inspection or in addition to that inspection, the proposed AD also would require replacement of certain rivets with certain new rivets in all applicable rib-to-stringer connections of the upper and lower wings. This proposal 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 the proposed AD are intended to prevent reduced structural integrity of the wings that is caused by problems associated with missing and/or loose rivets. DATES: Comments must be received by September 3, 1996. ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-103, Attention: Rules Docket No. 96-NM-28-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal holidays. The service information referenced in the proposed rule may be obtained from Fokker Aircraft USA, Inc., 1199 North Fairfax Street, Alexandria, Virginia 22314. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. FOR FURTHER INFORMATION CONTACT: Ruth E. Harder, Aerospace Engineer, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 227-1721; fax (206) 227-1149. SUPPLEMENTARY INFORMATION: Comments Invited Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this notice may be changed in light of the comments received. Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of [[Page 38408]] the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket. Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: ``Comments to Docket Number 96-NM-28-AD.'' The postcard will be date stamped and returned to the commenter. Availability of NPRMs Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-103, Attention: Rules Docket No. 96-NM-28-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Discussion The Rijksluchtvaartdienst (RLD), which is the airworthiness authority for the Netherlands, recently notified the FAA that an unsafe condition may exist on certain Fokker Model F27 Mark 100, 200, 300, 400, 500, 600, and 700 series airplanes. The RLD advises that it has received two reports indicating that the rivet heads were missing at the rib-to-stringer connections of the upper and lower wing skin at stringers 5 and 6, at wing stations 11260, 11860, 12660, and 13460. These incidents occurred on two airplanes that had accumulated 11,601 and 15,684 total flight cycles, respectively. Investigation revealed that the rivets on these airplanes have a lower than allowable tensile strength, which contributes to these rivets becoming loosened over time. Loose or missing rivets at the subject attachment areas could result in reduced structural integrity of the wing. Relevant Service Information Fokker has issued Service Bulletin F27/57-74, dated November 15, 1994, which describes procedures for 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 one-time visual inspection, or in addition to that inspection, the service bulletin also contains procedures for replacement of 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. The RLD classified this service bulletin as mandatory and issued Dutch airworthiness directive BLA 93-094 (A), dated July 16, 1993, in order to assure the continued airworthiness of these airplanes in the Netherlands. FAA's Conclusions This airplane model is manufactured in the Netherlands and is type certificated for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, the RLD has kept the FAA informed of the situation described above. The FAA has examined the findings of the RLD, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States. Explanation of Requirements of Rule Since an unsafe condition has been identified that is likely to exist or develop on other airplanes of the same type design, the proposed AD would 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, the proposed AD would require replacement of certain rivets with certain new rivets in all applicable rib-to-stringer connections of the upper and lower wings. The actions would be required to be accomplished in accordance with the service bulletin described previously. Cost Impact The FAA estimates that 6 Fokker Model 100, 200, 300, 400, 500, 600, and 700 series airplanes of U.S. registry would be affected by this proposed AD. The proposed inspection would take approximately 4 work hours per airplane to accomplish the proposed actions, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the proposed inspection action on U.S. operators is estimated to be $240 per airplane. The proposed replacement would take approximately 19 work hours per airplane to accomplish the proposed actions, at an average labor rate of $60 per work hour. The cost of required parts would be nominal. Based on these figures, the cost impact of the replacement proposed AD 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 proposed 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 proposed herein would 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 proposal would not have sufficient federalism implications to warrant the preparation of a Federalism Assessment. For the reasons discussed above, I certify that this proposed regulation (1) is not a ``significant regulatory action'' under Executive Order 12866; (2) is not a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) if promulgated, 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 copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES. List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Safety. The Proposed Amendment Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 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. Sec. 39.13 [Amended] 2. Section 39.13 is amended by adding the following new airworthiness directive: Fokker: Docket 96-NM-28-AD. Applicability: Model F27 Mark 100, 200, 300, 400, 500, 600, and 700 series airplanes, serial numbers 10653 through 10692 [[Page 38409]] 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. Issued in Renton, Washington, on July 18, 1996. Stewart R. Miller, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 96-18773 Filed 7-23-96; 8:45 am] BILLING CODE 4910-13-P