AD 2001-24-02

Effective January 4, 2002.

The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of January 4, 2002.

The service information referenced in this AD may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. This information may be examined at the Federal Aviation Administration (FAA), Transport Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

Keith Ladderud, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2780; fax (425) 227-1181.

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 Boeing Model 707-100, -100B, -300, and -E3A (military airplanes); 727-100 and -200; 737-200, -200C, -300, -400, and -500; 747SP and 747SR; 747-100B, -200B, -200C, -200F, -300, -400, and -400D; 757-200 and -200PF; and 767-200 and -300 series airplanes was published in the Federal Register on June 27, 2001 (66 FR 34128). That action proposed to require inspection of the attachment of the shoulder restraint harness to the mounting bracket on certain observer and attendant seats to determine if a C-clip is used in the attachment, and corrective action, if necessary.

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

One commenter states that the proposed AD does not apply to its fleet.

Two commenters request that the FAA withdraw the proposed AD. One commenter states that, on its fleet of Model 757 series airplanes, it has not observed any in-service problems with the shoulder restraint harness detaching from the mounting bracket. Therefore, it does not accept that the proposed modification is necessary.

The FAA does not concur. Though the commenter has not observed any problems related to the identified unsafe condition, at least two other operators have. Therefore, we find that it is necessary to require the modification in this AD.

Another commenter requests that the FAA withdraw the proposed rule because Boeing needs to revise the referenced service bulletins by identifying the individual part numbers of affected seats, rather than identifying the airplanes by serial numbers. The commenter is concerned that the service bulletins and proposed AD identify the subject seats both as “attendant” and “observer” seats. The commenter notes that the term “observer seat” could be construed to include observer seats in the cockpit, which have a different restraint system. The commenter is also concerned that, because the service bulletins identify affected airplanes, not seat part numbers, operators that move seats from one airplane to another could inadvertently install an unmodified seat on an airplane on which all other subject seats have already been modified.

We do not concur that it is necessary to withdraw the proposed rule. The restraint system is attached to the airplane, not to the attendant and observer seats; therefore, identifying the seats by part number would not provide any benefit. Also, the fact that when a seat is moved from one airplane to another, the restraint system for that seat remains with the airplane, should alleviate the commenter's concerns about exchanging seats between airplanes. Furthermore, although the commenter states that airplanes in its fleet have a restraint system on the cockpit observer seats other than the one addressed by this AD, other operators do have airplanes equipped with cockpit observer seats that employ the restraint system identified in this AD. No change to the AD is necessary in this regard.

One of the commenters who requests withdrawal of the proposed rule asks us to extend the compliance time for the proposed AD if we do not concur to withdraw the proposed rule. The commenter suggests that we extend the compliance time from 18 to 24 months. The commenter's rationale is that it has not observed the unsafe condition on any of its airplane fleet (Model 757 series airplanes).

We concur with the request to extend the compliance time of this AD. In developing a new compliance time for this AD, we considered not only the manufacturer's recommendation, but the degree of urgency associated with addressing the subject unsafe condition, and the average utilization of the affected fleet. In light of all of these factors, we find a 36-month compliance time for initiating the required actions to be warranted, in that it represents an appropriate interval of time allowable for affected airplanes to continue to operate without compromising safety. We have revised paragraph (a) of this AD accordingly.

One commenter requests that the “Differences Between The Service Bulletins and This Proposed AD” section of the proposed rule be revised to state that only two instances of detachment of the shoulder restraint harness of the attendant or observer seat from the mounting bracket have been reported, though this design has been in use for more than 40 years.

We acknowledge the commenter's remarks on the number of occurrences of the unsafe condition and the duration of service of the design. However, the section referred to by the commenter is not restated in this final rule. Therefore, no change to the AD is necessary in this regard.

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.

The table below estimates the cost impact of the inspection that is required by this AD. The average labor rate is $60 per work hour.

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 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.

The 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.

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.

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:

1. The authority citation for part 39 continues to read as follows:

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