2010-16606. Airworthiness Directives; The Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747SR, and 747SP Series Airplanes

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to supersede an existing airworthiness directive (AD) that applies to certain Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747SR, and 747SP series airplanes. The existing AD requires repetitive inspections and torque checks of the hanger fittings and strut forward bulkhead of the forward engine mount and adjacent support structure, and visual inspections of the internal angle and external bulkhead chord and detailed inspection of internal angles, and corrective actions if necessary. The existing AD also provides for an optional inspection. This proposed AD would also require additional inspections of airplanes that have hi-lok bolts and collars at all of the Group B fastener locations, except fastener 13, and related investigative and corrective actions. This proposed AD would require repetitive inspections of the internal angle and corrective actions, if necessary. This proposed AD also would require, for certain airplanes, replacing the fasteners, which terminates certain repetitive inspections. This proposed AD results from the reports of undertorqued or loose fasteners, a cracked bulkhead chord, and a fractured back-up angle. We are proposing this AD to prevent loose fasteners and/or damaged or cracked hanger fittings, back-up angles, and bulkhead of the forward engine mount, which could lead to failure of the hanger fitting and bulkhead and consequent separation of the engine from the airplane.

DATES:

We must receive comments on this proposed AD by August 23, 2010.

ADDRESSES:

You may send comments by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
• Fax: [phone].
• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.
• Hand Delivery: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this proposed AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone [phone], extension 1; fax [phone]; e-mail [e-mail]; Internet https://www.myboeingfleet.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221 or 425-227-1152.

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (telephone [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Ken Paoletti, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2010-0679; Directorate Identifier 2009-NM-179-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD because of those comments.

We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD.

Discussion

On September 14, 2007, we issued AD 2007-19-19, Amendment 39-15210 (72 FR 53939, September 21, 2007), for certain Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747SR, and 747SP series airplanes. That AD requires repetitive inspections and torque checks of the hanger fittings and strut forward bulkhead of the forward engine mount and adjacent support structure, and visual inspections of the internal angle and external bulkhead chord and detailed inspection of internal angles, and corrective actions if necessary. The existing AD also provides for an optional inspection. That AD resulted from reports of undertorqued or loose fasteners, a cracked bulkhead chord, and a fractured back-up angle after operators accomplished the terminating action required by AD 2001-15-02, Amendment 39-12336 (66 FR 37884, July 20, 2001), which was superseded by AD 2007-19-19. We issued that AD to detect and correct loose fasteners and/or damaged or cracked hanger fittings, back-up angles, and bulkhead of the forward engine mount, which could lead to failure of the hanger fitting and bulkhead and consequent separation of the engine from the airplane.

Actions Since Existing AD Was Issued

The preamble to AD 2007-19-19 specifies that we consider the requirements “interim action” and that we were considering requiring the inspections and applicable related investigative and corrective actions specified in Part 7 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-54A2203, Revision 1, dated August 9, 2007, and we have determined that further rulemaking is indeed necessary; this proposed AD follows from that determination.

Relevant Service Information

AD 2007-19-19 cited Boeing Alert Service Bulletin 747-54A2203, Revision 1, dated August 9, 2007, as the relevant source of information. Since we issued AD 2007-19-19, the manufacturer has revised the service information. Boeing has released Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009.

Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009, specifies that hi-lok bolts and collars at all of the Group B fastener locations, except fastener 13, need to be replaced with bolts specified in the service bulletin within 18 months after the service bulletin is released. (Boeing Alert Service Bulletin 747-54A2203, dated August 31, 2000; and Revision 1, dated August 9, 2007; specified that the hi-lok bolts on these airplanes did not have to be replaced according to Part 6 of the Accomplishment Instructions if they met the inspection requirements of Part 2.) The related corrective actions are replacing the fasteners; removing loose fasteners; tightening all Group A and Group B fasteners; tightening all under-torqued or loose Group A and Group B fasteners; and removing loose fasteners, inspecting the hole, installing fasteners, and applying optional torque stripes. In addition, that service bulletin specifies that the fasteners on these airplanes need to be replaced in accordance with Part 6—Fastener Replacement. The related investigative actions are doing repetitive detailed inspections, a torque stripe inspection, and torque checks.

Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009, specifies a compliance time of within 90 days after the date of Revision 2 of that service bulletin for the Part 2 inspection, and within 18 months after the date of Revision 2 of that service bulletin for the Part 6 replacement. For the related investigative actions, that service bulletin specifies a compliance time ranging from before further flight to within 18 months after the fasteners are replaced. For the related corrective actions, that service bulletin specifies a compliance time ranging from before further flight to within 18 months after under-torqued or loose fasteners were found.

For all airplanes, Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009, clarifies the requirements for conditions in which the torque stripe is not applied and for which no under-torqued or loose fastener was found by reordering the steps. In addition, Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009, adds an option for supporting the engine weight, instead of removing the engine, in Part 7—HFEC Internal Angle Inspection of the Accomplishment Instructions of that service bulletin. Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009, also no longer includes the 60-month compliance time for doing Part 6 of the Accomplishment Instructions of that service bulletin.

FAA's Determination and Requirements of the Proposed AD

We have evaluated all pertinent information and identified an unsafe condition that is likely to develop on other airplanes of the same type design. For this reason, we are proposing this AD, which would supersede AD 2007-19-19 and would retain certain requirements of the existing AD. This proposed AD would also require repetitive inspections of the internal angle, and corrective actions if necessary, and this proposed AD would also require, for certain airplanes, replacing the fasteners.

Differences Between the Proposed AD and Service Information

The service information specifies to contact the manufacturer for instructions on how to repair certain conditions, but this AD requires repairing those conditions in one of the following ways:

• Using a method that we approve; or
• Using data that meet the certification basis of the airplane, and that have been approved by the Boeing Commercial Airplanes Organization Designation Authorization whom we have authorized to make those findings.

Part 7—HFEC Internal Angle Inspection of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009, also provides an option to support the engine weight rather than removing the engine. This AD requires the removal of the engine to perform the inspection.

Costs of Compliance

There are about 266 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

Action	Work hours	Average labor rate per hour	Parts	Cost per airplane	Number of U.S.- registered airplanes	Fleet cost
Actions (required by AD 2007-19-19)	40	$85	$0	$3,400	121	$411,400
Internal Angle Inspection (new proposed action)	16	85	0	1,360	121	164,560
Replacement of fasteners (new proposed action)	24	85	0	2,040	121	246,840

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. 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.

We are issuing this rulemaking 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 and placed it in the AD docket. 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
• Incorporation by reference
• 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 39—AIRWORTHINESS DIRECTIVES

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

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

§ 39.13

[Amended]

2. The FAA amends § 39.13 by removing Amendment 39-15210 (72 FR 53939, September 21, 2007) and adding the following new AD:

The Boeing Company: Docket No. FAA-2010-0679; Directorate Identifier 2009-NM-179-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by August 23, 2010.

Affected ADs

(b) This AD supersedes AD 2007-19-19, Amendment 39-15210.

Applicability

(c) This AD applies to The Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747SR, and 747SP series airplanes, certificated in any category; as identified in Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009.

Subject

(d) Air Transport Association (ATA) of America Code 54: Nacelles/Pylons.

Unsafe Condition

(e) This AD results from the development of a mandating action. The Federal Aviation Administration is issuing this AD to detect and correct loose fasteners and/or damaged or cracked hanger fittings, back-up angles, and bulkhead of the forward engine mount, which could lead to failure of the hanger fitting and bulkhead and consequent separation of the engine from the airplane.

Compliance

(f) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

Restatement of a Requirement of AD 2007-19-19, With Updated Service Information

Inspections and Related Investigative and Corrective Actions

(g) Except as provided by paragraphs (i), (l), and (n) of this AD: At the applicable compliance times and repeat intervals listed in Tables 1 and 2 of paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 747-54A2203, Revision 1, dated August 9, 2007, do the inspections and applicable related investigative and corrective actions in accordance with Parts 2 and 8 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-54A2203, Revision 1, dated August 9, 2007; or Revision 2, dated July 9, 2009. After the effective date of this AD, use only Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009.

New Requirements of This AD

Mandatory Initial and Repetitive Inspections and Related Investigative and Corrective Actions

(h) For all airplanes: Except as provided by paragraph (m) of this AD, at the applicable time in Table 2 of paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009, do the initial inspection and related investigative and corrective actions in accordance with Part 7 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009, except as required by paragraphs (k) and (n) of this AD. Repeat the inspection thereafter at the applicable time in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009.

(i) For airplanes that were inspected in accordance with Boeing Alert Service Bulletin 747-54A2203, dated August 31, 2000; or Revision 1, dated August 9, 2007; and that have hi-lock bolts and collars at all of the Group B fastener locations: Except as provided by paragraph (m) of this AD, at the applicable time in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009, do the initial inspection and related investigative and corrective actions in accordance with Part 2 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009, except as required by paragraph (n) of this AD. Repeat the inspection at the applicable interval in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009.

Replacement of Hi-Lok Group B Fasteners

(j) For airplanes that were inspected in accordance with Boeing Alert Service Bulletin 747-54A2203, dated August 31, 2000, and that have hi-lock bolts and collars at all of the Group B fastener locations: Within 18 months after the effective date of this AD, replace all hi-lok Group B fasteners in accordance with Part 6 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009. Repeat the inspection required by Part 2 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009, at the applicable interval in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009.

Exceptions to Service Bulletin

(k) Where Step 3 of Part 7 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-54A2203, Revision 1, dated August 9, 2007; or Revision 2, dated July 9, 2009; provides the option to support the engine weight instead of removing the engine, this AD does not allow that option. This AD requires that the engine be removed before performing the inspections required by paragraph (h) of this AD.

(l) Where Boeing Alert Service Bulletin 747-54A2203, Revision 1, dated August 9, 2007, specifies a compliance time after the date of that service bulletin, this AD requires compliance within the specified compliance time after October 9, 2007 (the effective date of AD 2007-19-19).

(m) Where Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009, specifies a compliance time after the date of Revision 1 or Revision 2 of that service bulletin, this AD requires compliance within the specified compliance time after the effective date of this AD.

(n) Where Boeing Alert Service Bulletin 747-54A2203, Revision 1, dated August 9, 2007; or Boeing Alert Service Bulletin 747-54A2203, Revision 2, dated July 9, 2009; specifies to contact Boeing for appropriate action, this AD requires, before further flight, repair of the discrepancy or replacement of the discrepant part using a method approved in accordance with the Boeing Commercial Airplanes Organization Designation Authorization or in accordance with the procedures specified in paragraph (p) of this AD.

Credit for Actions Previously Accomplished

(o) Actions performed before the effective date of this AD, in accordance with Boeing Alert Service Bulletin 747-53A2203, Revision 1, dated August 9, 2007, are acceptable for compliance with the corresponding actions specified in paragraphs (h), (i), and (j) of this AD.

Alternative Methods of Compliance (AMOCs)

(p)(1) The Manager, Seattle Aircraft Certification Office, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Ken Paoletti, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone]. Or, e-mail information to [e-mail].

(2) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your principal maintenance inspector (PMI) or principal avionics inspector (PAI), as appropriate, or lacking a principal inspector, your local Flight Standards District Office. The AMOC approval letter must specifically reference this AD.

(3) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD, if it is approved by the Boeing Commercial Airplanes Organization Designation Authorization who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD.

(4) AMOCs approved previously in accordance with AD 2007-19-19, Amendment 39-15210, are approved as AMOCs for the corresponding provisions of this AD.

Issued in Renton, Washington, on June 25, 2010.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.