AD 95-04-08

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.

Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.

Three commenters support the proposal.

One 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.

As 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.

After 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.

There 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.

The 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.

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.

For 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."

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. App. 1354(a), 1421 and 1423; 49 U.S.C. 106(g); and 14 CFR 11.89. § 39.13 - (Amended)

2. Section 39.13 is amended by adding the following new airworthiness directive: