[Federal Register Volume 63, Number 63 (Thursday, April 2, 1998)] [Rules and Regulations] [Pages 16111-16114] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 98-8538] ----------------------------------------------------------------------- DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. 97-NM-321-AD; Amendment 39-10444] RIN 2120-AA64 Airworthiness Directives; British Aerospace Model Viscount 744, 745, 745D, and 810 Series Airplanes AGENCY: Federal Aviation Administration, DOT. ACTION: Direct final rule; request for comments. ----------------------------------------------------------------------- SUMMARY: This amendment adopts a new airworthiness directive (AD) that is applicable to all British Aerospace Model Viscount 744, 745, 745D, and 810 series airplanes. This amendment requires repetitive inspections to detect cracking and corrosion of components of the engine nacelle subframe structure, and corrective action, if necessary; and replacement of any component that has reached its life limit (safe life) with a new or serviceable component. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified in this amendment are intended to ensure periodic replacement of certain engine nacelle subframe components that have reached their maximum life limits. Cracking and [[Page 16112]] corrosion of these components, if not detected and corrected in a timely manner, could result in reduced structural integrity of the engine nacelle subframe structure, separation of the engine from the airframe, and reduced controllability of the airplane. DATES: Effective July 1, 1998. The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of July 1, 1998. Comments for inclusion in the Rules Docket must be received on or before May 4, 1998. ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 97-NM-321-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. The service information referenced in this amendment may be obtained from British Aerospace Regional Aircraft Limited, Chadderton Division, Engineering Support, Greengate, Middleton, Manchester M24 1SA, England. This information may be examined 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. FOR FURTHER INFORMATION CONTACT: Norman B. Martenson, Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2110; fax (425) 227-1149. SUPPLEMENTARY INFORMATION: The Civil Aviation Authority (CAA), which is the airworthiness authority for the United Kingdom, notified the FAA that an unsafe condition may exist on all British Aerospace Model Viscount 744, 745, 745D, and 810 series airplanes. The CAA advises that it has received reports of cracking, attributed to fatigue and stress corrosion, found in the engine nacelle subframe structure. Such cracking and corrosion, if not detected and corrected in a timely manner, could result in reduced structural integrity of the engine nacelle subframe structure, separation of the engine from the airframe, and reduced controllability of the airplane. Explanation of Relevant Service Information British Aerospace has issued Viscount Alert Preliminary Technical Leaflet (PTL) 500, dated January 1, 1993; including Appendices 1 through 4 inclusive, dated November 1992, and Appendix 5, dated October 1992. This alert PTL describes procedures for the introduction of a program of inspections to detect cracking and corrosion of the components of the engine nacelle subframe structure. The program includes a schedule of the maximum inspection threshold or life limit (safe life), as applicable, for each component; and includes procedures for replacement of any component that has reached its life limit with a new or serviceable component. (A life limit is the operational limit allowed for a part before it must be replaced.) The CAA classified this alert PTL as mandatory and issued British airworthiness directive 008- 06-94 (undated) in order to assure the continued airworthiness of these airplanes in the United Kingdom. FAA's Conclusions This airplane model is manufactured in the United Kingdom and is type certificated for operation in the United States under the provisions of Sec. 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, the CAA has kept the FAA informed of the situation described above. The FAA has examined the findings of the CAA, 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 registered in the United States, this amendment is being issued to prevent reduced structural integrity of the engine nacelle subframe structure, separation of the engine from the airframe, and reduced controllability of the airplane. This amendment requires the actions specified by the alert PTL described previously; except as discussed below. Differences Between This Amendment and the Service Information Operators should note that, unlike the procedures described in the alert PTL, this amendment will not permit flight of any airplane having any strut that has exceeded its life limit after the initial inspection specified in the alert PTL. The FAA has determined that, because of the safety implications and consequences associated with exceeding the life of a life-limited part, any strut that is found to have exceeded its life limit must be replaced prior to further flight. In addition, while the alert PTL specifies that any discrepant part be replaced, this amendment allows operators the option to repair discrepant parts, in accordance with a method approved by the FAA. The FAA has included this option because small amounts of corrosion or fatigue damage may be repairable. Cost Impact The FAA estimates that 29 airplanes of U.S. registry will be affected by this amendment. It would require approximately 200 work hours per airplane to replace all struts when they have reached their life limits, at an average labor rate of $60 per work hour. Required parts would cost approximately $30,000 per airplane. Based on these figures, the cost impact on U.S. operators of this action is estimated to be $1,218,000, or $42,000 per life limit cycle. Should an operator be required to perform the visual inspection, it would take approximately 2 work hours, at an average labor rate of $60 per work hour. Based on these figures, the cost impact on U.S. operators of this action is estimated to be $120 per airplane, per visual inspection cycle. Should an operator be required to perform the eddy current inspection, it would take approximately 2 work hours, at an average labor rate of $60 per work hour. Based on these figures, the cost impact on U.S. operators of this action is estimated to be $120 per airplane, per eddy current inspection cycle. It would require approximately 200 work hours to perform the detailed inspection, at an average labor rate of $60 per work hour. Based on these figures, the cost impact on U.S. operators of this action is estimated to be $348,000, or $12,000 per airplane, per inspection cycle. 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 amendment were not adopted. The Direct Final Rule Procedure The FAA anticipates that this regulation will not result in adverse or negative comment and therefore is issuing it as a direct final rule. The FAA does not anticipate receipt of adverse or negative comments, since the affected airplanes may not be operated in a manner that would require compliance with this amendment. In accordance with 14 CFR 11.17, unless a written adverse or negative comment, or a written notice of intent to submit an [[Page 16113]] adverse or negative comment, is received within the comment period, the regulation will become effective on the date specified above. After the close of the comment period, the FAA will publish a document in the Federal Register indicating that no adverse or negative comments were received; at that time, the AD number will be specified, and the date on which the final rule will become effective will be confirmed. If the FAA does receive, within the comment period, a written adverse or negative comment, or written notice of intent to submit such a comment, a document withdrawing the direct final rule will be published in the Federal Register, and a notice of proposed rulemaking may be published with a new comment period. Comments Invited Although this action is in the form of a final rule and was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed. Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the 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 that summarizes each FAA-public contact concerned with the substance of this amendment will be filed in the Rules Docket. Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this rule must submit a self-addressed, stamped postcard on which the following statement is made: ``Comments to Docket Number 97-NM-321-AD.'' The postcard will be date stamped and returned to the commenter. 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. The FAA has determined that this regulation is noncontroversial and unlikely to result in adverse or negative comments. For reasons discussed in the preamble, I certify that this regulation (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) 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 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. Sec. 39.13 [Amended] 2. Section 39.13 is amended by adding the following new airworthiness directive: British Aerospace Regional Aircraft Limited (Formerly British Aerospace Commercial Aircraft Limited, Vickers-Armstrongs Aircraft Limited): Amendment 39-10444. Docket 97-NM-321-AD. Applicability: All Model Viscount 744, 745, 745D, and 810 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 (f) 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 reduced structural integrity of the engine nacelle subframe structure, separation of the engine from the airframe, and reduced controllability of the airplane, accomplish the following: (a) Prior to the accumulation of the number of landings corresponding to a strut's life limit (safe life), as specified in the ``Inspection Threshold Landings'' column of Table One, Two, Three, Four, Five, or Six (hereinafter referred to as ``the applicable Table''), as applicable, provided in British Aerospace Viscount Alert Preliminary Technical Leaflet (PTL) 500, dated January 1, 1993, including Appendices 1 through 4 inclusive, dated November 1992, and Appendix 5, dated October 1992; or within 100 flight hours after the effective date of this AD; whichever occurs later: Replace any strut that has reached its life limit, as specified in the applicable Table, with a serviceable strut, in accordance with the alert PTL. Thereafter, replace any strut before it exceeds its life limit with a serviceable strut in accordance with the alert PTL, until initiation of the replacement cycle for that strut, as specified in paragraph (d) of this AD. (b) Prior to the accumulation of the number of landings corresponding to a strut's inspection threshold, as specified in the ``Inspection Period Landings'' column of the applicable Table provided in British Aerospace Alert Viscount PTL 500, dated January 1, 1993, including Appendices 1 through 4 inclusive, dated November 1992, and Appendix 5, dated October 1992; or within 100 flight hours after the effective date of this AD; whichever occurs later: Perform a visual inspection to detect cracking of the strut end fittings, in accordance with paragraph 2.1, Part One, Accomplishment Instructions, of the alert PTL. Repeat the inspection thereafter at intervals not to exceed 100 flight hours, until initiation of the inspection cycle for the respective component, as specified in paragraph (d) of this AD. (c) Prior to the accumulation of the number of landings corresponding to a strut's inspection threshold, as specified in the ``Inspection Period Landings'' column in the applicable Table provided in British Aerospace Viscount Alert PTL 500, dated January 1, 1993, including Appendices 1 through 4 inclusive, dated November 1992, and Appendix 5, dated October 1992; or within 200 flight hours after the effective date of this AD; whichever occurs later: Perform an eddy current inspection to detect cracking of the strut end fittings, in accordance with paragraph 2.1, Part One, Accomplishment Instructions, of the alert [[Page 16114]] PTL. Repeat the inspection thereafter at intervals not to exceed 200 flight hours, until initiation of the inspection cycle for the respective component, as specified in paragraph (d) of this AD. (d) Within 6 months after the effective date of this AD, perform an inspection (surface eddy scan, rotating eddy bore, internal surface eddy scan, or radiographic, as applicable) to detect cracking and corrosion of components of the engine nacelle subframe; and replace any component that has exceeded its life limit; in accordance with paragraph 2.2, Part Two, Accomplishment Instructions, of British Aerospace Viscount Alert PTL 500, dated January 1, 1993, including Appendices 1 through 4 inclusive, dated November 1992, and Appendix 5, dated October 1992. Repeat the inspection(s) and replacement(s) thereafter at intervals not to exceed the inspection threshold or safe life for the applicable component, as specified in the ``Inspection Period Landings'' or the ``Inspection Threshold Landings'' column (respectively) of the applicable Table of the alert PTL. Accomplishment of the initial inspections/replacements for all struts as required by this paragraph constitutes terminating action for the inspection/ replacement requirements of paragraphs (a), (b), and (c) of this AD. (e) If any crack or corrosion is found during any inspection required by this AD: Prior to further flight, accomplish the actions required by either paragraph (e)(1) or (e)(2) of this AD, and continue to follow the inspection and replacement schedule in accordance with the applicable Table. (1) Replace the discrepant component with a serviceable component. Or (2) Repair the discrepant part in accordance with a method approved by the Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate. (f) 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. 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. (g) 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. (h) The actions shall be done in accordance with British Aerospace Alert Preliminary Technical Leaflet 500, dated January 1, 1993; including Appendices 1 through 4 inclusive, dated November 1992, and Appendix 5, dated October 1992. 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 British Aerospace Regional Aircraft Limited, Chadderton Division, Engineering Support, Greengate, Middleton, Manchester M24 1SA, England. 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: The subject of this AD is addressed in British airworthiness directive 008-06-94 (undated). (i) This amendment becomes effective on July 1, 1998. Issued in Renton, Washington, on March 25, 1998. Darrell M. Pederson, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 98-8538 Filed 4-1-98; 8:45 am] BILLING CODE 4910-13-U