Airworthiness directives: McDonnell Douglas,
[Federal Register: August 27, 2003 (Volume 68, Number 166)]
[Proposed Rules]
[Page 51518-51521]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr27au03-25]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
[Docket No. 2002-NM-105-AD]
RIN 2120-AA64
Airworthiness Directives; McDonnell Douglas Model DC-9-10, DC-9- 20, DC-9-30; DC-10-40, and DC-10-50 Series Airplanes; Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD-87) Airplanes; and Model MD-88 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 McDonnell Douglas transport category airplanes. This proposal would require an inspection of the upper lock link assembly of the nose landing gear (NLG) to determine the manufacturer, repetitive eddy current inspections for cracking, and modification or replacement if necessary. This proposal also would provide for optional terminating action for the repetitive inspections. This action is necessary to prevent fracture of the upper lock link
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assembly of the NLG, which could result in failure of the NLG to extend following a gear-down selection, and consequent gear-up landing, structural damage, and possible injury to passengers and crew. This action is intended to address the identified unsafe condition.
DATES: Comments must be received by October 14, 2003.
ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2002-NM-105-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays. Comments may be submitted via fax to (425) 227-1232. Comments may also be sent via the Internet using the following address: 9-anm-nprmcomment@faa.gov. Comments sent via fax or the Internet must contain ``Docket No. 2002-NM-105-AD'' in the subject line and need not be submitted in triplicate. Comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 or 2000 or ASCII text.
The service information referenced in the proposed rule may be obtained from Boeing Commercial Aircraft Group, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Data and Service Management, Dept. C1-L5A (D800-0024). This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.
FOR FURTHER INFORMATION CONTACT: Mike Lee, Aerospace Engineer, Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 90712; telephone (562) 627- 5325; fax (562) 627-5210.
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 action may be changed in light of the comments received.
Submit comments using the following format:
[sbull] Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
[sbull] For each issue, state what specific change to the proposed AD is being requested.
[sbull] Include justification (e.g., reasons or data) for each request.
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 action must submit a self-addressed, stamped postcard on which the following statement is made: ``Comments to Docket Number 2002-NM-105-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-114, Attention: Rules Docket No. 2002-NM-105-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.
Discussion
The FAA has received a report indicating that an operator of a Model DC-9-82 (MD-82) airplane was unable to extend the nose landing gear (NLG) during landing. As a result of this problem, the operator landed with the nose gear up, which caused moderate damage to the nose gear doors, avionics door, and adjacent structure. Investigation of the damage revealed that the upper lock link of the NLG was completely fractured. Boeing has determined that tool marks and/or rough surface finish across the parting plane can cause stress concentration and cracking along the forged parting plane of the upper lock link. The Component Maintenance Manual is being revised to incorporate minimum surface finish and height requirements for the upper lock link. Fracture of the upper lock link assembly of the NLG could result in failure of the NLG to extend following a gear-down selection, and consequent gear-up landing, structural damage, and possible injury to passengers and crew.
Explanation of Relevant Service Information
We have reviewed and approved Boeing Alert Service Bulletin DC9- 32A340, dated November 14, 2001, which describes procedures for a visual inspection of the upper lock link assembly of the NLG to determine if the part was manufactured by Ready Machine and Manufacturing Company, and (regardless of manufacturer) repetitive high frequency eddy current (HFEC) inspections for cracking of the assembly, and modification or replacement of the assembly with a new assembly if cracking is found. The modification includes chemically stripping the lock link assembly, verifying the distance between the machined surface and lower surface parting line, doing a fluorescent dye penetrant inspection for cracking, doing another HFEC inspection for cracking, shotpeening the machined surface, reidentifying the reworked upper link, and refinishing. The service bulletin also describes an adjustment and test for the nose gear linkages, and provides for optional terminating action for the repetitive inspections if no cracking is found. Accomplishment of the actions specified in the service bulletin is intended to adequately address the identified unsafe condition.
Explanation of Requirements of Proposed Rule
Since an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, the proposed AD would require accomplishment of the actions specified in the service bulletin described previously. The actions would be required to be accomplished in accordance with the service bulletin described previously, except that the proposed AD does not require submitting Appendix A (report of inspection findings), and except as discussed below.
Difference Between Proposed AD and Service Bulletin
The Accomplishment Instructions of the service bulletin describe procedures for completing a sheet to record and report negative inspection findings. However, this proposed AD would not require a report; we do not need this information from operators.
Changes to 14 CFR Part 39/Effect on the Proposed AD
On July 10, 2002, the FAA issued a new version of 14 CFR part 39 (67 FR
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47997, July 22, 2002), which governs the FAA's airworthiness directives system. The regulation now includes material that relates to altered products, special flight permits, and alternative methods of compliance. Because we have now included this material in part 39, we no longer need to include it in each individual AD.
Cost Impact
There are approximately 1,904 airplanes of the affected design in the worldwide fleet. The FAA estimates that 1,188 airplanes of U.S. registry would be affected by this proposed AD.
It would take approximately 1 work hour per airplane to accomplish the proposed visual inspection, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the proposed visual inspection on U.S. operators is estimated to be $71,280, or $60 per airplane.
It would take approximately 1 work hour per airplane to accomplish the proposed high frequency eddy current (HFEC) inspection, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the proposed HFEC inspection on U.S. operators is estimated to be $71,280, or $60 per airplane, per inspection cycle.
It would take approximately 11 work hours per airplane to accomplish the proposed modification, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the proposed modification on U.S. operators is estimated to be $784,080, or $660 per airplane.
It would take approximately 8 work hours per airplane to accomplish the proposed replacement, at an average labor rate of $60 per work hour. Required parts would cost approximately $9,981 per airplane. Based on these figures, the cost impact of the proposed replacement on U.S. operators is estimated to be $12,427,668, or $10,461 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 proposed AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions.
Regulatory Impact
The regulations proposed herein would not have a substantial direct effect 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, it is determined that this proposal would not have federalism implications under Executive Order 13132.
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
-
The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
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Section 39.13 is amended by adding the following new airworthiness directive:
McDonnell Douglas: Docket 200-NM-105-AD.
Applicability: Model DC-9-11, DC-9-12, DC-9-13, DC-9-14, DC-9- 15, and DC-9-15F airplanes; Model DC-9-21 airplanes; Model DC-9-31, DC-9-32, DC-9-32 (VC-9C), DC-9-32F (C-9A, C-9B), DC-9-33F, DC-9-34 airplanes; Model DC-9-41 airplanes; Model DC-9-51 airplanes; Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD- 87) airplanes; and Model MD-88 airplanes; as listed in Boeing Alert Service Bulletin DC9-32A340, dated November 14, 2001; certificated in any category.
Compliance: Required as indicated, unless accomplished previously.
To prevent fracture of the upper lock link assembly of the nose landing gear (NLG), which could result in failure of the NLG to extend following a gear-down selection, and consequent gear-up landing, structural damage, and possible injury to passengers and crew; accomplish the following:
One-Time Inspection
(a) Within 2,500 flight cycles after the effective date of this AD: Do a general visual inspection to determine if the upper lock link assembly of the NLG was manufactured by Ready Machine and Manufacturing Company (this can be identified by the letters ``RM'' or an ``F'' suffix adjacent to the serial numbers), per the Accomplishment Instructions of Boeing Alert Service Bulletin DC9- 32A340, excluding Appendix A, dated November 14, 2001. Then do the actions specified in paragraph (b) or (c) of this AD, as applicable.
Note 1: For the purposes of this AD, a general visual inspection is defined as: ``A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to enhance visual access to all exposed surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.''
Repetitive Inspections/Modification or Replacement, if Necessary
(b) If the upper lock link assembly of the NLG was manufactured by Ready Machine and Manufacturing Company: Within 2,500 flight cycles after the effective date of this AD, do a high frequency eddy current (HFEC) inspection of the assembly for cracking, per Condition 1 of the Accomplishment Instructions of Boeing Alert Service Bulletin DC9-32A340, excluding Appendix A, dated November 14, 2001.
(1) If no cracking is found, repeat the inspection at intervals not to exceed 4,000 flight cycles until accomplishment of paragraph (d) of this AD.
(2) If any cracking is found, before further flight, modify or replace the upper lock link assembly, as applicable, per the service bulletin.
(c) If the upper lock link assembly was not manufactured by Ready Machine and Manufacturing Company: Within 3,500 flight cycles after the effective date of this AD, do a HFEC inspection of the assembly for cracking, per Condition 2 of the Accomplishment Instructions of Boeing Alert Service Bulletin DC9-32A340, excluding Appendix A, dated November 14, 2001.
(1) If no cracking is found, repeat the inspection at intervals not to exceed 4,000 flight cycles until accomplishment of paragraph (d) of this AD.
(2) If any cracking is found, before further flight, modify or replace the upper lock link assembly, as applicable, per the service bulletin.
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Optional Terminating Action
(d) Modification or replacement of the upper lock link assembly of the NLG, as applicable, per Boeing Alert Service Bulletin DC9- 32A340, excluding Appendix A, dated November 14, 2001, terminates the repetitive inspections required by paragraph (b) or (c) of this AD, as applicable.
Alternative Methods of Compliance
(e) In accordance with 14 CFR 39.19, the Manager, Los Angeles Aircraft Certification Office, FAA, is authorized to approve alternative methods of compliance for this AD.
Issued in Renton, Washington, on August 21, 2003. Ali Bahrami, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.
[FR Doc. 03-21874 Filed 8-26-03; 8:45 am]
BILLING CODE 4910-13-P
