[Federal Register Volume 70, Number 21 (Wednesday, February 2, 2005)]
[Rules and Regulations]
[Pages 5361-5365]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-1724]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NM-279-AD; Amendment 39-13957; AD 2005-03-01]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to all Boeing Model 747 series airplanes, that requires 
repetitive inspections of the nacelle strut-to-wing attachment 
structure, and repetitive overhaul of the diagonal brace and spring 
beam load paths, to maintain damage tolerance requirements and ensure 
long-term structural integrity; and follow-on and corrective actions if 
necessary. This action is necessary to ensure the structural integrity 
of the strut-to-wing load path and prevent separation of the strut and 
engine from the airplane. This action is intended to address the 
identified unsafe condition.

DATES: Effective March 9, 2005.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of March 9, 2005.

ADDRESSES: The service information referenced in this AD may be 
obtained from Boeing Commercial Airplanes, 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 National 
Archives and Records Administration (NARA). For information on the 
availability of this material at NARA, call (202) 741-6030, or go to: 
http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

[[Page 5362]]


FOR FURTHER INFORMATION CONTACT: Tamara Anderson, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
917-6421; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION: 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 all Boeing Model 747 series 
airplanes was published in the Federal Register on September 18, 2003 
(68 FR 54680). That action proposed to require repetitive inspections 
of the nacelle strut-to-wing attachment structure, and repetitive 
overhaul of the diagonal brace and spring beam load paths, to maintain 
damage tolerance requirements and ensure long-term structural 
integrity; and follow-on and corrective actions if necessary.

Actions Since Notice of Proposed Rulemaking (NPRM) Was Issued

    Since the NPRM was issued, the FAA has reviewed Boeing Service 
Bulletin 747-54A2182, Revision 1, dated January 8, 2004. Revision 1 of 
the service bulletin describes procedures that are essentially the same 
as the procedures described in the original issue of the service 
bulletin, which was referenced in the NPRM as the appropriate source of 
service information. For certain airplanes, Revision 1 extends 
repetitive intervals for the baseline inspections. For certain other 
airplanes, Revision 1 revises the inspection method for the 
supplemental inspection of a certain structure, and reduces threshold 
and/or repetitive intervals of the supplemental inspections. Revision 1 
also adds repetitive torque checks of the fasteners of lower spar 
fitting for Groups 1 and 2 airplanes.
    We find that the additional work in Revision 1 of the service 
bulletin is acceptable for compliance with the requirements of this AD. 
Therefore, we have added new paragraph (f) to this AD to specify that, 
as an option, the required actions in paragraphs (b) through (e) of 
this AD may be accomplished in accordance with Revision 1. However, 
operators should note that if any action specified in this AD is done 
in accordance with Revision 1, then all of the actions in this AD and 
the additional actions specified in paragraph (g) of this AD must also 
be done in accordance with Revision 1 at the applicable compliance 
times specified in that service bulletin.
    Also since the NPRM was issued, Boeing has received a Delegation 
Option Authorization (DOA). We have revised this final rule to delegate 
the authority to approve an alternative method of compliance (AMOC) for 
any repair required by this AD to the Authorized Representative for the 
Boeing DOA Organization rather than the Designated Engineering 
Representative (DER).

Comments

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

Request To Issue a Supplemental NPRM

    One commenter requests that we issue a supplemental NPRM after 
Boeing Service Bulletin 747-54A2182, Revision 1, dated January 8, 2004, 
is published. The commenter states that changes to the service bulletin 
will have a direct impact on the requirements of the proposed AD, and 
that ``if this AD is deemed necessary, the AD should not be released 
until it incorporates that revision.'' The commenter also states that 
since Revision 1 has not yet been published, the commenter does not 
fully understand the changes made to the service bulletin.
    We do not agree with the request to issue a supplemental NPRM. As 
discussed previously, we have reviewed Revision 1 of the service 
bulletin, which was published after issuance of the NPRM. We agree that 
Revision 1 of the service bulletin is acceptable for compliance with 
the requirements of this AD and have added Revision 1 to this final 
rule as an option for accomplishing the requirements of paragraphs (b) 
through (e) of this AD. Therefore, it is not necessary to reopen the 
comment period by issuing an supplemental NPRM. No other change to the 
final rule is necessary in this regard.

Request To Include Changes to Revision 1 in This Final Rule

    Another commenter requests that we include all changes to Revision 
1 of the service bulletin in this final rule, since the changes 
significantly affect fleet maintenance and operations. The commenter 
states that the changes in Revision 1 are based on comments received 
from operators through telex traffic and meetings, and that the Boeing 
Designated Engineer Representative (DER) has recommended that the FAA 
approve Revision 1.
    We partially agree with the commenter. For the reasons discussed 
previously, we have added Revision 1 of the service bulletin to this 
final rule as an option for accomplishing the requirements of 
paragraphs (b) through (e) of this AD. No other change to the final 
rule is necessary in this regard.

Request To Remove Detailed Inspection

    One commenter considers unwarranted the detailed inspection ``to 
verify correct installation anytime a fuse pin or secondary pin joint 
is disassembled within 1,200 flight-cycles or 18 months, whichever is 
earlier.'' The commenter states that installation instructions ``in the 
appropriate airplane maintenance manuals when followed and signed for 
by licensed maintenance personnel should not require a special 
subsequent inspection at future set time to verify correct 
installation.'' The commenter also asserts that a required inspection 
item at the time of installation may be more effective and appropriate. 
We infer that the commenter requests that we remove the above-stated 
detailed inspection from the proposed AD.
    We partially agree with the inferred request to remove the above-
stated detailed inspection from this final rule. Although the original 
issue of the service bulletin recommends accomplishing that detailed 
inspection, Revision 1 does not recommend its accomplishment for 
compliance with this final rule. Therefore, the commenter may choose to 
accomplish Revision 1, which has been added as an alternative source of 
service information for this final rule as discussed previously. If the 
commenter chooses to accomplish the original issue of the service 
bulletin, under the provisions of paragraph (h) of this final rule, we 
may consider requests for approval of an AMOC if sufficient data are 
submitted to substantiate that such a design change would provide an 
acceptable level of safety. Therefore, no further change to the final 
rule is necessary in this regard.

Request To Revise Corrective Action

    One commenter requests that we revise paragraph (e) of the proposed 
AD, so that defects found during the baseline inspections may be 
repaired in accordance with an FAA-acceptable method. The commenter 
states that, while Parts 1 through 9 of the service bulletin specify to 
contact Boeing for rework requirements and additional inspections if 
any damage is found or structural integrity is not verified, paragraph 
(e) of the proposed AD would require that these corrective actions be 
repaired per a method approved by the FAA, or per data approved by a 
Boeing DER. The commenter considers the method of repair specified in 
paragraph (e) of the proposed AD unnecessarily burdensome, especially 
for correcting relatively simple defects such as

[[Page 5363]]

missing or broken fasteners. Furthermore, the commenter believes that 
the corrective action for a defect found during a normal maintenance 
period should not require AMOC approval.
    We do not agree with the request to revise paragraph (e) of this 
final rule because of the known, possible consequences of discrepancies 
found in the nacelle strut-to-wing attachment structure. We also do not 
agree with the request because the damage allowables and corrective 
action are undefined in the service bulletin. We retain approval 
authority for 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. Therefore, no change to the final 
rule is necessary in this regard.

Request for Flight Standards District Office (FSDO) Approval

    One commenter requests that we revise the proposed AD to allow 
approval for changes in compliance time ``through the operators Flight 
Standards District Office as per their established procedures,'' rather 
than by the Manager of the Seattle ACO. The commenter states that the 
repetitive baseline inspections, and possibly the supplemental 
inspections, should be given the same flexibility as any other 
maintenance program requirement. The commenter also asserts that, in 
order for operators to integrate the proposed AD into their FAA-
approved maintenance program, the approval of inspection escalation 
should be made through the operator's Flight Standards District 
Offices.
    We do not agree. The inspection interval of the supplemental 
inspection is based on complex engineering analysis that meets the 
damage tolerance requirements of Section 25.571 (``Damage--tolerance 
and fatigue evaluation of structure'') of the Federal Aviation 
Regulations (14 CFR 25.571) as upgraded in the Type Certificate Data 
Sheet for Boeing Model 747 series airplanes. If that inspection 
interval is changed, the damage tolerance requirements may not be met.
    Separation of the strut and engine from the airplane prior to strut 
modification resulted in two accidents with fatalities on Model 747 
series airplanes. In addition, there have been numerous structural 
issues even after strut modification. Under the provisions of paragraph 
(h) of this final rule, we may approve requests for adjustments to the 
compliance time if data are submitted to substantiate that such an 
adjustment would provide an acceptable level of safety. Therefore, no 
change to the final rule is necessary in this regard.

Consideration for a Change to the Maintenance Program

    Two commenters consider the proposed AD an inappropriate use of an 
airworthiness directive. One commenter states that the recommendations 
specified in the original issue of the service bulletin appear better 
suited for implementation via Maintenance Review Board (MRB) and 
associated Maintenance Planning Data (MPD) documents, with the 
exception of the check for the part number of the side link fuse pins.
    Another commenter states that the service bulletin/AD process is an 
inappropriate method for enacting changes to the required maintenance 
programs. The commenter also states that the FAA should work together 
with manufacturers and operators to develop a better method of revising 
the maintenance, inspection, and overhaul requirements for large, 
transport category aircraft. Furthermore, the commenter believes ``that 
appropriate revisions to the Maintenance Review Board Document, the 
Maintenance Planning Document and/or the Aircraft Limitation 
Instruction are warranted.'' The commenter also notes that the proposed 
AD would be applicable to all future Model 747 series airplanes that 
are yet to be built with the current strut design.
    We do not agree that the proposed AD is an inappropriate use of an 
airworthiness directive. We are requiring the post strut modification 
inspections in Boeing Alert Service Bulletin 747-54A2182, dated July 
12, 2001; or Boeing Service Bulletin 747-54A2182, Revision 1, dated 
January 8, 2004; to meet the upgraded certification basis of the strut-
to-wing attachments as listed in the Type Certificate Data Sheet for 
Model 747 series airplanes. The certification basis was upgraded to a 
higher level of safety due to accidents involving the strut-to-wing 
attachments. To adequately address the unsafe condition, we are 
mandating the post strut modification inspections as recommended in the 
service bulletin by the airplane manufacturer to meet the new 
certification basis.
    Furthermore, certain airplanes have been delivered with MPD 
documents that do not require accomplishing these inspections, so we 
are mandating the inspections with an AD. Note that an operator is only 
required to accomplish inspections included in the MPD delivered with 
the airplane; inspections added in subsequent revisions to the MPD are 
not mandatory until we mandate them with an AD. Therefore, we find that 
this final rule is the least complex and most timely method to mandate 
new inspections, if the inspections were not included in the MPD 
delivered with an airplane. For commonality, we have mandated the 
inspections for all Model 747 series airplanes through a service 
bulletin developed by the manufacturer. We may consider revising the 
applicability of the AD if the inspections in the service bulletin are 
incorporated in the airworthiness limitation section of the MPD, which 
is provided with the airplane upon delivery from the production line 
for future airplanes. Therefore, no change to the final rule is 
necessary in this regard.

Additional Change to This AD

    Operators should note that, although the Accomplishment 
Instructions of the referenced service bulletins specify to report 
damaged or cracked fuse pins to the manufacturer, this AD would not 
require those actions. We do not need this information from operators.

Conclusion

    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 with the changes previously 
described. The FAA has determined that these changes will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.

Cost Impact

    There are approximately 991 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 187 airplanes of U.S. registry 
will be affected by this AD.
    It will take approximately 280 work hours per airplane to 
accomplish the repetitive baseline, supplemental, and fuse pin 
inspections at an average labor rate of $65 per work hour. Based on 
these figures, the cost impact of the inspections, per inspection 
cycle, on U.S. operators is estimated to be $3,403,400 for the fleet, 
or $18,200 per airplane.
    It will take approximately 48 work hours per airplane to overhaul 
the diagonal brace, at an average labor rate of $65 per work hour. 
Based on these figures, the cost impact of the overhaul, per overhaul 
cycle, on U.S. operators is

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estimated to be $583,440 for the fleet, or $3,120 per airplane.
    It will take approximately 40 work hours per airplane overhaul the 
spring beam, at an average labor rate of $65 per work hour. Based on 
these figures, the cost impact of the overhaul, per overhaul cycle, on 
U.S. operators is estimated to be $486,200 for the fleet, or $2,600 per 
airplane.
    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.

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 AD.

Regulatory Impact

    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.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
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

0
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]

0
2. Section 39.13 is amended by adding the following new airworthiness 
directive:

2005-03-01 Boeing: Amendment 39-13957. Docket 2001-NM-279-AD.

    Applicability: All Model 747 series airplanes, certificated in 
any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To ensure the structural integrity of the strut-to-wing load 
path and prevent separation of the strut and engine from the 
airplane, accomplish the following:

Compliance Times

    (a) Where the compliance times for the initial and repetitive 
baseline and supplemental inspections in the Accomplishment 
Instructions of Boeing Alert Service Bulletin 747-54A2182, dated 
July 12, 2001; or Boeing Service Bulletin 747-54A2182, Revision 1, 
dated January 8, 2004; specify a compliance time interval calculated 
``from the release of this service bulletin,'' this AD requires 
compliance within the interval specified in the service bulletin 
``after the effective date of this AD.''

Inspections/Follow-On Actions

    (b) Do the initial and repetitive baseline and supplemental 
inspections of the nacelle strut-to-wing attachment structure for 
discrepancies (including cracks, corrosion, or damage; and loose, 
missing, or broken fasteners), and do the applicable follow-on 
actions; by doing all the actions in Part 1 through Part 9 of the 
Work Instructions of Boeing Alert Service Bulletin 747-54A2182, 
dated July 12, 2001. Do the inspections (including inspections for 
correct installation of hardware and part numbers) and follow-on 
actions at the applicable times specified in Figure 1 of the service 
bulletin.
    (c) Do the initial and repetitive overhauls of the diagonal 
brace and spring beam load paths by doing all the actions in Part 10 
and Part 11 of the Work Instructions of Boeing Alert Service 
Bulletin 747-54A2182, dated July 12, 2001. Do the initial and 
repetitive overhauls at the applicable times specified in Part 10 
and Part 11 of the service bulletin.
    (d) Do the initial and repetitive inspections of the fuse pins 
and secondary pins of the strut-to-wing attachment by doing all the 
actions in Part 12 of the Work Instructions of Boeing Alert Service 
Bulletin 747-54A2182, dated July 12, 2001. Do the inspections at the 
times specified in Part 12 of the service bulletin.

Corrective Actions

    (e) If any discrepancy is found during any inspection required 
by this AD: Before further flight, do all applicable corrective 
actions specified in Part 1 through Part 12 of the Work Instructions 
of Boeing Alert Service Bulletin 747-54A2182, dated July 12, 2001. 
Do the applicable corrective actions per the service bulletin. If 
the service bulletin specifies to contact the manufacturer for 
appropriate action: Before further flight, repair per a method 
approved by the Manager, Seattle Aircraft Certification Office 
(ACO), FAA, or per data meeting the type 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 such findings.

Optional Service Bulletin

    (f) As an option, paragraphs (b) through (e) of this AD may be 
done in accordance with Part 1 through Part 12, as applicable, of 
the Work Instructions of Boeing Service Bulletin 747-54A2182, 
Revision 1, dated January 8, 2004, at the applicable times specified 
in the service bulletin. If any action specified in paragraphs (b) 
through (e) of this AD is done in accordance with Revision 1 of the 
service bulletin, do all of the actions specified in paragraphs (b) 
through (e) of this AD and the additional actions specified in 
paragraph (g) of this AD, in accordance with Revision 1 of the 
service bulletin. If the service bulletin specifies to contact the 
manufacturer for appropriate action: Before further flight, repair 
per a method approved by the Manager, Seattle ACO, FAA, or per data 
meeting the type 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 such findings.

Additional Actions for Optional Service Bulletin

    (g) If, as an option, any action specified in paragraphs (b) 
through (e) of this AD is done in accordance with Boeing Service 
Bulletin 747-54A2182, Revision 1, dated January 8, 2004, of the 
service bulletin, do a detailed inspection of all strut-to-wing 
attach joints to determine the part number of any dual side link 
fuse pin; and install the correct fuse pin

[[Page 5365]]

if any incorrect fuse pin is found; by doing all of the actions 
specified in the ``Initial Base Line Inspection Requirements'' of 
the Work Instructions of Revision 1 of the service bulletin. Do 
these actions at the applicable times specified in Revision 1 of the 
service bulletin.

    Note 1: For the purposes of this AD, a detailed inspection is 
``An intensive examination of a specific item, installation, or 
assembly to detect damage, failure, or irregularity. Available 
lighting is normally supplemented with a direct source of good 
lighting at an intensity deemed appropriate. Inspection aids such as 
mirror, magnifying lenses, etc., may be necessary. Surface cleaning 
and elaborate procedures may be required.''

No Reporting Requirement

    (h) Although the service bulletins referenced in this AD specify 
to submit certain information to the manufacturer, this AD does not 
include that requirement.

Alternative Methods of Compliance (AMOC)

    (i)(1) In accordance with 14 CFR 39.19, the Manager, Seattle 
ACO, FAA, is authorized to approve AMOCs for this AD.
    (2) An AMOC that provides an acceptable level of safety may be 
used for a 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 such findings.

Incorporation by Reference

    (j) Unless otherwise specified in this AD, the actions shall be 
done in accordance with Boeing Alert Service Bulletin 747-54A2182, 
dated July 12, 2001. 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 Boeing 
Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207. 
Copies may be inspected at the FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington; or at the National 
Archives and Records Administration (NARA). For information on the 
availability of this material at NARA, call (202) 741-6030, or go 
to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

Effective Date

    (k) This amendment becomes effective on March 9, 2005.

    Issued in Renton, Washington, on January 18, 2005.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 05-1724 Filed 2-1-05; 8:45 am]
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