The service bulletin specifies that if no discrepancies are found during the inspections, either repeat Part 1 and Part 4, or do Part 4 and Part 3 (terminating action).

The service bulletin specifies that if any discrepancies are found during the inspections, the corrective actions include doing Part 4 and Part 2; or doing Part 4 and Part 3 (terminating action); as applicable.

The service bulletin also specifies that Part 2 may be done instead of Part 1.

Part 2Bearing Corrosion Removal and ReLubrication

The service bulletin describes the following inspections and rework of the DSB bearings and associated parts, and other specified actions.

The service bulletin specifies that if no discrepancies are found during the actions specified in Part 2: Either repeat both Part 1 and Part 4, and Part 4 and Part 2; or do Part 4 and Part 3 (terminating action).

The service bulletin specifies that if any discrepancies are found during the actions specified in Part 2, the corrective actions include repeating both Part 1 and Part 4, and Part 4 and Part 2; or doing Part 4 and Part 3 (terminating action); as applicable. The corrective actions also include replacing any damaged bushings/eccentric bushings/ fuse pins/bolts with new or serviceable bushings/eccentric bushings/ fuse pins/bolts; and contacting Boeing for additional instructions. Part 3Dual Side Brace Bearing Replacement and Side Link Modification

The service bulletin describes procedures for replacing the strut and wing side DSB bearings with new or serviceable strut and wing side bearings (includes, for Groups 3 and 4, installing cups per Part 7), modifying side links, and doing related investigative and corrective actions.

Related investigative actions include the following inspections:

Corrective actions include replacing any damaged fuse pin with a new or serviceable fuse pin; contacting Boeing for additional instructions; oversizing the lug bore; and replacing any damaged bearing with a new or serviceable bearing.

Part 4Underwing Midspar Fitting Inspection

The service bulletin describes an inspection to determine the gap between the underwing midspar fitting and strut midspar fitting.

The service bulletin specifies that if the gap is within limits specified in the service bulletin no further action is required.

The service bulletin specifies that if the gap is not within limits specified in the service bulletin, the corrective action includes doing Part 4 and Part 3 (terminating action) or doing Part 3, Part 5, and Part 6 (terminating action), as applicable.

Part 5Underwing Midspar Fitting Inspection and Rework

The service bulletin describes procedures to do a detailed inspection of the underwing midspar fitting lugs, strut spring beam lugs and bushings, and strut fitting lugs for damage, and corrective action if necessary.

The corrective action includes reworking the underwing midspar fitting, spring beams, and strut fitting; and contacting Boeing for additional instructions.
Part 6Dual Side Brace Fitting and Underwing Midspar Fitting Tension Bolt Inspection

The service bulletin describes procedures to do a detailed inspection of the dual side brace fitting and underwing fittings for missing or fractured tension bolts or for broken sealant around the fasteners; and do a detailed inspection of the visible areas of the underwing fitting lugs and strut fitting lugs or spring beam lugs for damage; and corrective action if necessary. The corrective action is [[Page 7448]]
repairing any damage and contacting Boeing for additional instructions. Part 7Vapor Seal Web Cup Installation

The service bulletin describes procedures for Groups 3 and 4 to install cups for the vapor seal web.

Accomplishing the actions specified in the service information is intended to adequately address the unsafe condition.

FAA's Determination and Requirements of the Proposed AD

We have evaluated all pertinent information and identified an unsafe condition that is likely to exist or develop on other airplanes of this same type design. Therefore, we are proposing this AD, which would require accomplishing the actions specified in the service information described previously, except as discussed under ``Differences Between the AD and the Service Bulletin.''

The FAA is not proposing to mandate the optional terminating action for several reasons:

1. Accessing the areas for inspection at the intervals is easily accomplished.

2. The inspection items are easily performed by means of a detailed inspection.

3. Longterm continued operational safety in this case will be adequately ensured by repetitive inspections to prevent the loss of a DSB or underwing midspar fitting load path.
Differences Between the Proposed AD and the Service Bulletin

The service bulletin specifies that you may contact the manufacturer for instructions on how to repair certain conditions, but this proposed AD would require you to repair those conditions in one of the following ways:

Costs of Compliance

There are about 1,091 airplanes of the affected design in the worldwide fleet. The following table provides the estimated costs for U.S. operators to comply with this proposed AD.
Estimated Costs Number of Average Cost per U.S. Action Work hours labor rate Parts airplane registered Fleet cost per hour airplanes Part 1

Inspections, per inspection 8 $65 None................ $520 229 $119,080, per inspection cycle. cycle.

Part 2

Inspections, per inspection 48 65 None................ 3,120 229 714,480, per inspection cycle. cycle.

Part 4

Inspections, per inspection 4 65 None................ 260 229 59,540, per inspection cycle. cycle.

Authority for this Rulemaking

The FAA's authority to issue rules regarding aviation safety is found in Title 49 of the United States Code. Subtitle I, Section 106 describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the agency's authority.

This rulemaking is promulgated under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, ``General requirements.'' Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

We have determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD 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.

For the reasons discussed above, I certify that the 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. 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.

We prepared a regulatory evaluation of the estimated costs to comply with this proposed AD. See the ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Safety. The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows: PART 39AIRWORTHINESS DIRECTIVES

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

Authority: 49 U.S.C. 106(g), 40113, 44701.

Sec. 39.13 [Amended]

2. The FAA amends Sec. 39.13 by adding the following new airworthiness directive (AD):
Boeing: Docket No. FAA200520364; Directorate Identifier 2004NM 186AD.
Comments Due Date
(a) The Federal Aviation Administration (FAA) must receive comments on this AD action by March 31, 2005.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Boeing Model 747100, 747100B, 747100B SUD, 747200B,
[[Page 7449]]
747200C, 747200F, 747300, 747400, 747400D, 747400F, 747SR, and 747SP series airplanes; certificated in any category; as identified in Boeing Alert Service Bulletin 74754A2218, dated June 17, 2004. Unsafe Condition
(d) This AD was prompted by reports of corroded, migrated, and rotated bearings for the dual side braces (DSB) in the inboard and outboard struts, a report of a fractured retainer for the eccentric bushing for one of the side links of a DSB, and reports of wear and damage to the underwing midspar fitting on the outboard strut. We are issuing this AD to prevent the loss of a DSB or underwing midspar fitting load path, which could result in the transfer of loads and motion to other areas of a strut, and possible separation of a strut and engine from the airplane during flight.
Compliance
(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
Inspections and Corrective Action
(f) At the times specified in Figure 1 of Boeing Alert Service Bulletin 74754A2218, dated June 17, 2004, except as provided by paragraph (g) of this AD: Do the various inspections and other specified actions in the figure to detect discrepancies of the dual side braces, underwing midspar fittings, and associated parts, by doing all of the actions specified in Parts 1, 2, and 4; and the applicable corrective actions specified in Parts 3, 5, 6, and 7; of the Accomplishment Instructions of the service bulletin, except as provided by paragraph (h) of this AD. Repeat the inspections and other specified actions thereafter at the intervals specified in Figure 1 of the service bulletin. Accomplishment of any terminating action specified in Figure 1 of the service bulletin terminates the inspections and other specified actions.
(g) Where Boeing Alert Service Bulletin 74754A2218, dated June 17, 2004, recommends an initial compliance threshold of ``within 24 months after the original issue date on this service bulletin'' for Parts 1 and 4 of the service bulletin, and of ``within 72 months after the original issue date on this service bulletin'' for Part 2 of the service bulletin, this AD requires an initial compliance threshold of ``within 24 months after the effective date of this AD'' for Parts 1 and 4 of the service bulletin and of ``within 72 months after the effective date of this AD'' for Part 2 of the service bulletin.
(h) If any damage or crack is found during any inspection or corrective action required by this AD, before further flight, repair in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 74754A2218, dated June 17, 2004; except, where the service bulletin specifies to contact Boeing, before further flight, repair according to a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or according to data meeting the certification basis of the airplane approved by an Authorized Representative for the Boeing Delegation Option Authorization Organization who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the approval must specifically refer to this AD.
Alternative Methods of Compliance (AMOCs)
(i)(1) The Manager, Seattle ACO, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.
(2) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD, if it is approved by an Authorized Representative for the Boeing Delegation Option Authorization Organization who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the approval must specifically refer to this AD.

Issued in Renton, Washington, on February 7, 2005. Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification Service.
[FR Doc. 052762 Filed 21105; 8:45 am]
BILLING CODE 491013P

FOR FURTHER INFORMATION CONTACT

Ivan Li, Aerospace Engineer, Airframe Branch, ANM120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 980554056; telephone (425) 9176437; fax (425) 9176590.