AD 2000-08-18

This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-9 series airplanes, and Model MD-88 and MD-90-30 airplanes, that requires replacement of the lanyard assembly pins of the evacuation slides with solid corrosion-resistant pins. This amendment is prompted by a report that, due to stress corrosion on the lanyard pins, the arms of the lanyard assembly of the evacuation slide were found to be frozen. The actions specified by this AD are intended to prevent the improper deployment of the evacuation slide due to stress corrosion, which could delay or impede evacuation of passengers during an emergency.

Final rule

2000-08-18 MCDONNELL DOUGLAS: Amendment 39-11704. Docket 97-NM-244-AD. \n\n\tApplicability: Model DC-9 series airplanes, and Model MD-88 airplanes, as listed in McDonnell Douglas Alert Service Bulletin DC9-25A357, Revision 02, dated May 28, 1998; and Model MD-90-30 airplanes, as listed in McDonnell Douglas Alert Service Bulletin MD90-25A019, dated February 11, 1997; certificated in any category. \n\n\tNOTE 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 (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. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo prevent the improper deployment of the evacuation slide, which could delay or impede evacuation of passengers during an emergency, accomplish the following: \n\nReplacement \n\t(a)\tWithin 180 days after the effective date of this AD, replace the lanyard assembly pins of the evacuation slides with solid corrosion-resistant pins, in accordance with McDonnell Douglas Alert Service Bulletin MD80-25A357, dated February 11, 1997, Revision 01, dated March 16, 1998, or Revision 02, dated May 28, 1998 (for Model DC-9 series airplanes and Model MD-88 airplanes); or McDonnell Douglas Alert Service Bulletin MD90-25A019, dated February 11, 1997 (for Model MD-90-30 airplanes); as applicable. \n\nSpares \n\t(b)\tAs of the effective date of this AD, no lanyard assembly, part number (P/N) 3961899-1 or P/N 3956939-501, shall be installed on any airplane unless that assembly has been modified in accordance with the requirements of paragraph (a) of this AD. \n\nAlternative Methods of Compliance \n\t(c)\tAn 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, Los Angeles Aircraft Certification Office (ACO), 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, Los Angeles ACO. \n\n\tNOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles ACO. \n\nSpecial Flight Permits \n\t(d)\tSpecial 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 alocation where the requirements of this AD can be accomplished. \n\nIncorporation by Reference \n\t(e)\tThe replacement shall be done in accordance with McDonnell Douglas Alert Service Bulletin MD80-25A357, dated February 11, 1997; McDonnell Douglas Alert Service Bulletin DC9-25A357, Revision 01, dated March 16, 1998; McDonnell Douglas Alert Service Bulletin DC9-25A357, Revision 02, dated May 28, 1998; or McDonnell Douglas Alert Service Bulletin MD90-25A019, dated February 11, 1997; as applicable. 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 Boeing Commercial Aircraft Group, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Technical Publications Business Administration, Dept. C1-L51 (2-60). Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Transport Airplane Directorate, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. \n\n\t(f)\tThis amendment becomes effective on June 13, 2000.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to certain McDonnell Douglas Model DC-9 series airplanes, and Model MD-88 and MD-90-30 airplanes was published as a supplemental notice of proposed rulemaking (NPRM) in the Federal Register on November 26, 1999 (64 FR 66417). That action proposed to require replacement of the lanyard assembly pins of the evacuation slides with solid corrosion-resistant pins. \n\nComments Received \n\tInterested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received. \n\nSupport for Proposed AD \n\tOne commenter supports the proposed AD. Another commenter states that the proposed AD does not affect its fleet. \n\nRequests To Revise Applicability Statement of Proposed AD \n\tTwo commenters request that the applicability statement of the proposed AD be revised to exclude freighter airplanes on which emergency evacuation slides have not been installed. The commenters state that such a revision would eliminate alternative method of compliance (AMOC) requests. The commenters did not provide any data to substantiate their request. \n\n\tThe FAA does not concur. The FAA is unable to verify that all freighter airplanes are not equipped with evacuation slides. Therefore, all affected freighter airplanes must be included in the applicability statement of the final rule. However, under the provisions of paragraph (c) of the final rule, the FAA may consider requests for approval of an AMOC if sufficient data are submitted to substantiate that replacement of the lanyard pins with solid corrosion-resistant pin are not necessary. \n\n\tOne commenter questions whether Boeing latch assembly, part number (P/N) 69-70843-1, should be included in the applicability statement of the proposed AD. The commenter states that the roll pin, P/N MS39086-140, which resulted in the corrosion problem, is present in the Boeing latch assembly, as well as the Douglas latch assembly, P/N's 3961899-1 and 3956939-501. \n\n\tThe FAA has determined that the subject Boeing latch assemblies are not susceptible to stress corrosion, and therefore, are not subject to the identified unsafe condition of this AD. Therefore, no change to the final rule is necessary. \n\nRequests for Alternative Method of Compliance (AMOC) \n\tOne commenter requests that the FAA approve lanyard assembly pin, P/N MS16555-627, as an AMOC for the pin required by the AD (reference McDonnell Douglas Alert Service Bulletin DC9-25A357, dated February 11, 1997). The commenter states that this pin is shorter and would not require any machining. If the FAA does not approve the pin having P/N MS16555-627, the commenter requests that the FAA approve the installation of an unmodified pin, P/N MS16555-628, which would protrude from the latch assembly. The commenter states that both of these alternatives would not interfere with the operation of the lanyard or deployment of the slide and would provide the same level of safety as the pin required by the AD. \n\n\tThe FAA does not concur. The FAA finds that the shorter pin would not provide an equivalent level of safety to that of the pin required by the AD, because the taper on the end of the shorter pin would not provide the same level of pin retention. The shorter pin could become loose and fall out of the latch, thus causing the latch to fail. The FAA also finds that a pin that extends past the surface of the latch could cause the latch to hang up and fail. Therefore, no change to the final rule is necessary. \n\n\tOne commenter requests that the proposed AD be revised to include an AMOC, which was approved by the airplane manufacturer, to eliminate the need of each airline making a request to the FAA on an individual basis. The commenter states that the AMOC involves a program to accomplish, among otherthings, an initial check of the lanyard and then to periodically check, clean, and refurbish the subject lanyards with new roll pins of the same P/N. \n\n\tThe FAA does not concur. Because Airplane Maintenance Programs vary from operator to operator, there are no assurances that each operator's Airplane Maintenance Program contains the identical actions required by this AD. However, under the provisions of paragraph (c) of the final rule, the FAA may consider requests for approval of an AMOC if sufficient data are submitted to substantiate that such an AMOC would provide an acceptable level of safety. \n\nConclusion\n\tAfter careful review of the available data, including the comments noted above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed. \n\nCost Impact \n\tThere are approximately 2,167 McDonnell Douglas Model DC-9 series airplanes, and Model MD-88 and MD-90-30 airplanes of the affected design in the worldwide fleet. The FAA estimates that 1,200 airplanes of U.S. registry will be affected by this AD, that it will take approximately 2 work hours per airplane to accomplish the required actions, and that the average labor rate is $60 per work hour. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $144,000, or $120 per airplane. \n\n\tThe cost impact figure discussed above is 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 AD were not adopted. \n\nRegulatory Impact \n\n\tThe regulations adopted herein will 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 final rule does not have federalism implications under Executive Order 13132. \n\n\tFor thereasons discussed above, I certify that this action (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) 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 final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption "ADDRESSES." \n\nList of Subjects in 14 CFR Part 39 \n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. \n\nAdoption of the Amendment \n\tAccordingly, 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: \n\nPART 39 - AIRWORTHINESS DIRECTIVES \n\t1. The authority citation for part 39 continues to read as follows: \nAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\n§ 39.13 (Amended) \n\t2. Section 39.13 is amended by adding the following new airworthiness directive: