[Federal Register Volume 61, Number 166 (Monday, August 26, 1996)] [Proposed Rules] [Pages 43689-43690] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 96-21596] ----------------------------------------------------------------------- DEPARTMENT OF TRANSPORTATION 14 CFR Part 39 [Docket No. 95-NM-232-AD] RIN 2120-AA64 Airworthiness Directives; Dornier Model 328-100 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 Dornier Model 328-100 series airplanes. This proposal would require replacement of certain hydraulic fuses of the landing gear with improved fuses. This proposal is prompted by results of extended testing, which revealed that the hydraulic fuses of the landing gear failed to operate due to movement of the end of the spring within the fuses over the end of the flange of the spool. The actions specified by the proposed AD are intended to prevent such failure, which could result in external leakage in the brake lines downstream of the respective fuse and consequent loss of hydraulic fluid; this condition, if not corrected, could result in partial loss of the main hydraulic power supply. DATES: Comments must be received by October 4, 1996. ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-103, Attention: Rules Docket No. 95-NM-232-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 Dornier Luftfahrt GmbH, P.O. Box 1103, D-82230 Wessling, Germany. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. FOR FURTHER INFORMATION CONTACT: Connie Beane, Aerospace Engineer, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 227-2796; 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 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 95-NM-232-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. 95-NM-232-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Discussion The Luftfahrt-Bundesamt (LBA), which is the airworthiness authority for Germany, recently notified the FAA that an unsafe condition may exist on certain Dornier 328-100 series airplanes. The LBA advises that, during extended testing of this airplane model, the hydraulic fuses of the landing gear failed to operate due to movement of the end of the spring within the fuses over the end of the flange of the spool. If a hydraulic fuse fails to operate, external leakage could occur in the brake lines downstream of the respective fuse and loss of hydraulic fluid could occur. This condition, if not corrected, could result in partial loss of the main hydraulic power supply. Explanation of Relevant Service Information Dornier has issued Service Bulletin SB-328-32-048, dated August 11, 1994, which describes procedures for replacement of certain hydraulic fuses of the landing gear with fuses having an improved design. The LBA classified [[Page 43690]] this service bulletin as mandatory and issued German airworthiness directive 95-051, dated February 3, 1995, in order to assure the continued airworthiness of these airplanes in Germany. FAA's Conclusions This airplane model is manufactured in Germany 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 LBA has kept the FAA informed of the situation described above. The FAA has examined the findings of the LBA, 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 Proposed 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 replacement of certain hydraulic fuses of the landing gear with fuses having an improved design. The actions would be required to be accomplished in accordance with the service bulletin described previously. Explanation of Proposed Compliance Time Operators should note that, although the Dornier Service Bulletin SB-328-25-072 recommends accomplishment of the described procedures within 45 days, this AD would require accomplishment of the actions within 90 days. Based upon an analysis of the unsafe condition, the FAA finds that a compliance time of 90 days will address the unsafe condition in a timely manner. In developing an appropriate compliance time for this AD, the FAA considered not only the safety implications and the degree of urgency associated with addressing the subject unsafe condition, but the maximum interval of time allowable for all affected airplanes to continue to operate without compromising safety. The FAA finds 90 days to be an appropriate compliance time for accomplishing these actions. Cost Impact The FAA estimates that 5 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 2 work hours per airplane to accomplish the proposed actions, and that the average labor rate is $60 per work hour. Required parts would be provided by the manufacturer at no cost to operators. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $600, or $120 per airplane. The cost impact figure discussed above is 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. 39.13 [Amended] 2. Section 39.13 is amended by adding the following new airworthiness directive: Dornier: Docket 95-NM-232-AD Applicability: Model 328-100 series airplanes; serial numbers 3005 through 3008 inclusive, 3010, 3011, and 3012; certificated in any category. Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise 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 partial loss of the main hydraulic power supply due to loss of hydraulic fluid, accomplish the following: (a) Within 90 days after the effective date of this AD, replace landing gear hydraulic fuses having part number ACM30488, MOD states 2 through 6, with MOD 7 fuses in accordance with Dornier Service Bulletin SB-328-32-048, dated August 11, 1994. (b) As of the effective date of this AD, no person shall install a landing gear hydraulic fuse having part number ACM30488, MOD states 2 through 6, on any airplane. (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, 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. (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. Issued in Renton, Washington, on August 19, 1996. Darrell M. Pederson, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 96-21596 Filed 8-23-96; 8:45 am] BILLING CODE 4910-13-U