AD 95-04-08

This amendment adopts a new airworthiness directive (AD), applicable to Boeing Model 747-300 and -400 series airplanes equipped with certain stretched upper deck evacuation slides manufactured by BFGoodrich series airplanes. This amendment requires modification of the slide's main restraint strap, regulator assembly, and turbo fan flapper retaining roll pins. This amendment is prompted by reports of loss of air pressure and non-inflation of the inflatable tubes of the slide due to problems associated with the restraint strap, regulator assembly, and turbo fan flapper retaining roll pins. The actions specified by this AD are intended to prevent loss of air pressure or non-inflation of the inflatable tubes of the slide, which could impede the successful evacuation of passengers from the airplane during an emergency.

Final rule

95-04-08 BOEING: Amendment 39-9160. Docket 94-NM-153-AD.\n\n\tApplicability: Model 747-300 and -400 series airplanes equipped with BFGoodrich stretched upper deck evacuation slides, part number (P/N) 7A1323-1, -2, -3, -4, -105, -106, -107, -108, -109, or -110; 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 use the authority provided in paragraph (b) to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition; or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any airplane from the applicability of this AD. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo prevent loss of air pressure or non-inflation of the inflation tubes of an evacuation slide, which could impede the evacuation of passengers from the airplane during an emergency, accomplish the following: \n\n\t(a)\tWithin 36 months after the effective date of this AD, modify the BFGoodrich stretched upper deck evacuation slide, P/N 7A1323-( ), in accordance with the Accomplishment Instructions of BFGoodrich Service Bulletin 7A1323-25-266, Revision 1, dated September 30, 1994. \n\n\tNOTE 2: Installation of the "product improvements," specified in paragraph 2.J. of the Accomplishment Instructions of the service bulletin, is not required by this AD. \n\n\t(b)\tAn alternative method of compliance or adjustment of thecompliance 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 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles ACO. \n\n\t(c)\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 a location where the requirements of this AD can be accomplished. \n\n\t(d)\tThe modification shall be done in accordance with BFGoodrich Service Bulletin 7A1323- 25-266, Revision 1, dated September 30, 1994. 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 BFGoodrich Company, Aircraft Evacuation Systems, Dept. 7916, Phoenix, Arizona 85040. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Los Angeles Aircraft Certification Office, Transport Airplane Directorate, 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(e)\tThis amendment becomes effective on April 6, 1995.

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 Boeing Model 747- 300 and -400 series airplanes equipped with BFGoodrich stretched upper deck evacuation slides, Part Number 7A1323-( ), was published in the Federal Register on November 30, 1994 (59 FR 61296). That action proposed to require modification of the slide's main restraint strap, regulator assembly, and turbo fan flapper retaining roll pins. \n\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\n\tThree commenters support the proposal. \n\n\tOne commenter requests that the description of the report that prompted the proposal be clarified. The preamble to the notice stated that the proposed action was based, in part, on a report indicating that, "during deployment of the slide, the turbo fan flapper retaining roll pin broke, allowing the flapper to fall out." The commenter wishes to clarify that the reported incident occurred during the deployment of a slide that was equipped with roll pins that are common to those used on the stretched upper deck escape slide; however, there have been no reports of roll pins breaking during deployment of stretched upper deck slides that are the subject of the proposed rule. The FAA acknowledges this clarification. \n\n\tAs a result of recent communications with the Air Transport Association (ATA) of America, the FAA has learned that, in general, some operators may misunderstand the legal effect of AD's on airplanes that are identified in the applicability provision of the AD, but that have been altered or repaired in the area addressed by the AD. The FAA points out that all airplanes identified in the applicability provision of an AD are legally subject to the AD. If an airplane has been altered or repaired in the affected area in such a way as to affect compliance with the AD, the owner or operator is required to obtain FAA approval for an alternative method of compliance with the AD, in accordance with the paragraph of each AD that provides for such approvals. A note has been added to this final rule to clarify this long-standing requirement. \n\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, with the addition of the clarifying note previously described. The FAA has determined that the addition of the clarifying note will neither increase the economic burden on any operator nor increase the scope of the AD. \n\n\tThere are approximately 900 BFGoodrich stretched upper deck evacuation slides of the affected design installed on Boeing Model 747 series airplanes worldwide. The FAA estimates that 100 of these slides are installed on airplanes of U.S. registry that are affected by this AD. It will take approximately 4.5 work hours per slide to accomplish the required actions, at an average labor rate of $60 per work hour. Required parts will cost approximately $1,402 per slide assembly. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $167,200, or $1,672 per slide. \n\n\tThe total 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\n\tThe 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. \n\n\tFor the reasons 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\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. \n\nAdoption of the Amendment \n\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\n PART 39 - AIRWORTHINESS DIRECTIVES \n\n\t1.\tThe authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 106(g); and 14 CFR 11.89. § 39.13 - (Amended) \n\n\t2.\tSection 39.13 is amended by adding the following new airworthiness directive: