[Federal Register Volume 61, Number 235 (Thursday, December 5, 1996)] [Proposed Rules] [Pages 64492-64494] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 96-30967] ----------------------------------------------------------------------- DEPARTMENT OF TRANSPORTATION 14 CFR Part 39 [Docket No. 96-NM-114-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 modification of the electrical circuits for certain avionics by rewiring and adding electrical devices. This proposal is prompted by reports indicating that failure of an engine or direct current (DC) generator during takeoff and landing, coupled with an open DC tie, could cause the avionics to fail. The actions specified by the proposed AD are intended to prevent the failure of those avionics during takeoff and landing, which consequently could result in the inability of the flight crew to respond to and control the associated systems during these critical phases of flight. DATES: Comments must be received by January 17, 1997. ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-103, Attention: Rules Docket No. 96-NM-114-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 [[Page 64493]] 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-114-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-114-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 Model 328-100 series airplanes. The LBA advises that it has received reports indicating that the failure of an engine or direct current (DC) generator during takeoff and landing, coupled with an open DC tie in the airplane's electrical system, could cause failure of the No. 2 primary flight and multiple function displays, or the autopilot/yaw damper servos. The failure of these avionics during takeoff and landing, if not prevented, could result in the inability of the flight crew to respond to and control the systems associated with these avionics during these critical phases of flight. Explanation of Relevant Service Information Dornier has issued Service Bulletin SB-328-24-062, Revision 1, dated June 27, 1995, which describes procedures for modification of the wiring that supplies power from the non-essential bus 2 to the bus 2 avionics circuit, and from the non-essential bus 1 to the bus 1 avionics circuit. This modification entails the rewiring of these circuits and the addition of certain electrical devices. This modification is intended to correct circuit logic and wiring design discrepancies that could cause these circuits to fail if the DC tie in the electrical system remains open during takeoff and landing. The LBA classified this service bulletin as mandatory and issued German airworthiness directive 95-284, dated August 4, 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 registered in the United States, the proposed AD would require modification of the wiring that supplies power from the non-essential bus 2 to the bus 2 avionics circuit, and from the non-essential bus 1 to the bus 1 avionics circuit, by rewiring these circuits and adding electrical devices. The actions would be required to be accomplished in accordance with the service bulletin described previously. Cost Impact The FAA estimates that 9 Dornier Model 328-100 series airplanes of U.S. registry would be affected by this proposed AD. It would take approximately 220 work hours per airplane to accomplish the proposed modification, at an average labor rate of $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 $118,800, or $13,200 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. Sec. 39.13 [Amended] 2. Section 39.13 is amended by adding the following new airworthiness directive: Dornier: Docket 96-NM-114-AD. Applicability: Model 328-100 series airplanes having serial numbers 3005 through 3024 inclusive; 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 (b) 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 failure, during takeoff and landing, of the No. 2 primary flight and multiple function displays, or the autopilot/ [[Page 64494]] yaw damper servos, which consequently could result in the inability of the flight crew to respond to and control the systems associated with these avionics during these critical phases of flight, accomplish the following: (a) Within 6 months after the effective date of this AD, modify the wiring that supplies power from the non-essential bus 2 to the bus 2 avionics circuit, and from the non-essential bus 1 to the bus 1 avionics circuit, in accordance with Dornier Service Bulletin SB- 328-24-062, Revision 1, dated June 27, 1995. (b) 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. (c) Special flight permits may be issued in accordance with Secs. 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 November 29, 1996. Darrell M. Pederson, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 96-30967 Filed 12-4-96; 8:45 am] BILLING CODE 4910-13-U