AD 2008-11-13
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 777-200 Series | Airworthiness Directives; Boeing Model 777-200, -200LR, -300, and -300ER Series Airplanes |
| aircraft | The Boeing Company | 777-200LR Series | Airworthiness Directives; Boeing Model 777-200, -200LR, -300, and -300ER Series Airplanes |
| aircraft | The Boeing Company | 777-300 Series | Airworthiness Directives; Boeing Model 777-200, -200LR, -300, and -300ER Series Airplanes |
| aircraft | The Boeing Company | 777-300ER Series | Airworthiness Directives; Boeing Model 777-200, -200LR, -300, and -300ER Series Airplanes |
Unsafe Condition
Potential for ignition sources inside fuel tanks caused by latent failures, alterations, repairs, or maintenance actions, which could result in fuel tank explosions and consequent loss of the airplane.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Revise the Airworthiness Limitations (AWLs) section of the Instructions for Continued Airworthiness to incorporate new limitations for fuel tank systems. Perform initial repetitive inspections specified in the AWLs to phase in those inspections, and repair if necessary.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Before further flight.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Boeing Model 777-200, -200LR, -300, and -300ER series airplanes.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 777-200, -200LR, -300, and -300ER series airplanes. This AD requires revising the Airworthiness Limitations (AWLs) section of the Instructions for Continued Airworthiness by incorporating new limitations for fuel tank systems to satisfy Special Federal Aviation Regulation No. 88 requirements. This AD also requires the initial performance of certain repetitive inspections specified in the AWLs to phase in those inspections, and repair if necessary. This AD results from a design review of the fuel tank systems. We are issuing this AD to prevent the potential for ignition sources inside fuel tanks caused by latent failures, alterations, repairs, or maintenance actions, which, in combination with flammable fuel vapors, could result in fuel tank explosions and consequent loss of the airplane.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 73, Number 104 (Thursday, May 29, 2008)]
[Rules and Regulations]
[Pages 30737-30743]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: E8-11467]
=======================================================================
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2007-28389; Directorate Identifier 2006-NM-171-AD;
Amendment 39-15536; AD 2008-11-13]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 777-200, -200LR, -300, and
-300ER Series Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain Boeing Model 777-200, -200LR, -300, and -300ER series
airplanes. This AD requires revising the Airworthiness Limitations
(AWLs) section of the Instructions for Continued Airworthiness by
incorporating new limitations for fuel tank systems to satisfy Special
Federal Aviation Regulation No. 88 requirements. This AD also requires
the initial performance of certain repetitive inspections specified in
the AWLs to phase in those inspections, and repair if necessary. This
AD results from a design review of the fuel tank systems. We are
issuing this AD to prevent the potential for ignition sources inside
fuel tanks caused by latent failures, alterations, repairs, or
maintenance actions, which, in combination with flammable fuel vapors,
could result in fuel tank explosions and consequent loss of the
airplane.
DATES: This AD becomes effective July 3, 2008.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in the AD as of July 3, 2008.
ADDRESSES: For service information identified in this AD, contact
Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-
2207.
Examining the AD Docket
You may examine the AD docket on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a>; 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 AD, the regulatory evaluation,
any comments received, and other information. The address for the
Docket Office (telephone 800-647-5527) is the Document Management
Facility, U.S. Department of Transportation, Docket Operations, M-30,
West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE.,
Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT: Margaret Langsted, Aerospace Engineer,
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification
Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone
(425) 917-6500; fax (425) 917-6590.
SUPPLEMENTARY INFORMATION:
Discussion
The FAA issued a supplemental notice of proposed rulemaking (NPRM)
to amend 14 CFR part 39 to include an AD that would apply to certain
Boeing Model 777-200, -200LR, -300, and -300ER series airplanes. That
supplemental NPRM was published in the Federal Register on February 28,
2008 (73 FR 10698). That supplemental NPRM proposed to require revising
the Airworthiness Limitations (AWLs) section of the Instructions for
Continued Airworthiness (ICA) by incorporating new limitations for fuel
tank systems to satisfy Special Federal Aviation Regulation No. 88
(SFAR 88) requirements. That supplemental NPRM also proposed to require
the initial performance of certain repetitive inspections specified in
the AWLs to phase in those inspections, and repair if necessary.
Actions Since NPRM Was Issued
Since we issued the NPRM, Boeing has issued Temporary Revision (TR)
09-014, dated December 2007. Boeing TR 09-014 is published as Section 9
of the Boeing 777 Maintenance Planning Document (MPD) Document,
D622W001-9, Revision February 2008 (hereafter referred to as ``Revision
February 2008 of the MPD''). The supplemental NPRM referred to Revision
October 2007 of the MPD as the appropriate source of service
information for accomplishing the proposed actions. Revision February
2008 of the MPD revises AWL No. 28-AWL-03 to reflect the new maximum
loop resistance values associated with the lightning protection of the
unpressurized fuel quantity indicating system (FQIS) wire bundle
installations.
Accordingly, we have revised paragraphs (f), (g), and (h) of this
AD to refer to Revision February 2008 of the MPD. We also have added a
new paragraph (j) to this AD specifying that actions done before the
effective date of this AD in accordance with Revision October 2007 or
Revision December 2007 of the MPD are acceptable for compliance with
the corresponding
[[Page 30738]]
requirements of paragraphs (g) and (h) of this AD.
Operators should note that we have revised paragraph (g)(2) of this
AD to require incorporating only AWLs No. 28-AWL-01 through No. 28-AWL-
20 inclusive. AWLs No. 28-AWL-21 through No. 28-AWL-26 were added in
Revision December 2007 of the MPD for Model 777-200LR series airplanes
equipped with an auxiliary fuel tank. We might issue additional
rulemaking to require the incorporation of those AWLs. However, as an
optional action, operators may incorporate those optional AWLs as
specified in paragraph (g)(2) of this AD. Operators should also note
that we might issue a separate NPRM that proposes to incorporate AWL
No. 28-AWL-19 and No. 28-AWL-20 into the AWLs section of the ICA and
the associated design change.
Comments
We provided the public the opportunity to participate in the
development of this AD. We have considered the comments received.
Support for the Supplemental NPRM
Boeing, American Airlines, and United Airlines (UAL) concur with
the contents of the supplemental NPRM. The Air Transport Association
(ATA) agrees with the intent of the supplemental NPRM.
Request for Clarification of Paragraph (g)
The ATA, on behalf of UAL, submitted a comment stating that there
might be a logic error in the proposed requirement of paragraph (g) of
the supplemental NPRM. UAL states that it understands that the proposed
action is to revise the AWLs section of the ICA to ``Incorporate the
MPD into the MPD.''
We infer that the commenters request that we clarify the
requirements of paragraph (g) of this AD. We agree that clarification
is necessary. The intent of paragraph (g) of this AD is to require the
operator to incorporate Subsections D and E of Revision February 2008
of the MPD into the operator's existing MPD. We have deleted the words
``into the MPD'' from paragraph (g) of this AD to eliminate any
confusion.
Request To Revise the Loop Resistance Values for AWL No. 28-AWL-03
The ATA, on behalf of Continental Airlines (CAL), submitted a
request to revise the loop resistance values for AWL No. 28-AWL-03 of
Revision October 2007 of the MPD to reflect the appropriate limits for
in-service airplanes. CAL states that the limits in AWL No. 28-AWL-03
reflect factory limits, and that mandating those limits would result in
non-compliance and ground the Model 777 fleet. CAL states that the
limits in AWL No. 28-AWL-03 should be harmonized with the limits in
Tables 601 and 602 of Task 05-55-54-200-801 of the Boeing 777 Airplane
Maintenance Manual (AMM), which contain bonding resistance values for
in-service airplanes. CAL further requests that the new limits be
published before May 2008, so that operators have adequate time to
develop the necessary task cards before the required compliance time of
paragraph (g) of this AD.
We agree that the loop resistance values for AWL No. 28-AWL-03 of
Revision October 2007 of the MPD needed to be revised. Boeing published
Revision February 2008 of the MPD to specify the appropriate values,
which agree with the AMM. As stated previously, we have revised this AD
accordingly.
Request To Clarify Paragraph (i)
The ATA, on behalf of UAL, requests that we clarify paragraph (i)
of the supplemental NPRM. UAL interprets paragraph (i) to mean that,
prior to the accomplishment of paragraphs (g) and (h) of the
supplemental NPRM, an operator is allowed to use alternative
inspections, inspection intervals, or critical design configuration
control limitations (CDCCLs), which are not part of subsequent
revisions of Revision October 2007 of the MPD. UAL states that, if this
interpretation is true, then paragraph (i) might be in conflict with
section 121.1113 (``Fuel tank system maintenance program'') of the
Federal Aviation Regulations (14 CFR 121.1113). UAL asks us to clarify
whether paragraph (i) suspends the intent of 14 CFR 121.1113 and allows
deviations until paragraphs (g) and (h) are complied with.
We disagree with UAL's interpretation that this AD conflicts with
14 CFR 121.1113. The two requirements are entirely compatible. That
section requires that, no later than December 16, 2008, operators must
incorporate applicable inspections, procedures, and limitations for
fuel tank systems that have been approved under SFAR 88. The AWLs
required by this AD are a portion of the SFAR 88 documents approved for
these airplanes. Since the compliance date for this AD was chosen to
coincide with the compliance date for 14 CFR 121.1113, compliance with
this AD by that date will also be partial compliance with 14 CFR
121.1113, and neither that section nor this AD impose requirements
before that date. Paragraph (i) of this AD is also consistent with 14
CFR 121.1113 in that both prohibit changing the requirements unless the
changes are approved by the Seattle Aircraft Certification Office
(ACO), which is the oversight office for this airplane model. No change
to this AD is necessary in this regard.
Request To Clarify Use of Equivalent Tools and Chemicals
JAL requests that we provide guidelines for using equivalent tools
and chemical materials according to the component maintenance manuals
(CMMs). JAL states that normally operators can use equivalents without
FAA approval when the CMM specifies that equivalents may be used. JAL
also states that it has received further clarification from Boeing
specifying that unless a CDCCL refers to a certain tool by part number
or certain chemicals by name, an operator can continue to use
equivalent tools or materials according to the CMMs.
We acknowledge the commenter's request and are working with Boeing
to provide appropriate flexibility while still ensuring that items
critical for maintaining safety continue to be specifically identified
in the CMMs. However, to delay issuance of this AD would be
inappropriate.
We agree that when the CMMs allow use of equivalent tools or
chemical materials, operators and repair stations may use equivalents.
We have already approved the use of the CMMs at the revision levels
specified in Revision February 2008 of the MPD, including the use of
equivalent tools or chemicals where the CMMs state equivalents are
allowed. If the CMM does not allow use of an equivalent, none may be
used. No change to this AD is necessary in this regard.
Request To Delete Reference to Task Cards
All Nippon Airways (ANA) requests that we delete the words ``and
task card,'' unless the task card references are listed in Subsection D
of the MPD or Appendix 1 of the AD. Those words are located in the
following sentence in the ``Ensuring Compliance with Fuel Tank System
AWLs'' section of the original NPRM: ``Operators that do not use
Boeing's revision service should revise their maintenance manuals and
task cards to highlight actions tied to CDCCLs to ensure that
maintenance personnel are complying with the CDCCLs.'' ANA believes
that if a task card refers to the AMM, which includes the CDCCL note,
then highlighting the CDCCL items is not necessary because they are
already highlighted in the
[[Page 30739]]
AMM and maintenance personnel always refer to the AMM. ANA further
states that the applicable task card references are not listed in
Subsection D of the MPD, or in Appendix 1 of the original NPRM; they
refer only to the AMM. ANA, therefore, states that it is difficult to
find out or distinguish the affected task card.
JAL believes that the proposed requirement regarding the CDCCLs is
to incorporate the manufacturer's maintenance manuals into an
operator's maintenance manual. If the description of a CDCCL is missing
from the manufacturer's AMM, then JAL believes that operators are not
responsible for the requirements of the AD.
We agree that the task cards might not need to be revised because
an operator might find that the AMM notes are sufficient. However, we
disagree with deleting the reference to the task cards since some
operators might need to add notes to their task cards. This AD does not
require any changes to the maintenance manuals or task cards. The AD
requires incorporating new AWLs into the operator's maintenance
program. It is up to the operator to determine how best to ensure
compliance with the new AWLs. In the ``Ensuring Compliance with Fuel
Tank System AWLs'' section of the original NPRM, we were only
suggesting, not requiring, ways that an operator could implement CDCCLs
into its maintenance program. We have not changed this AD in this
regard.
Request To Clarify Meaning of Task Cards
JAL requests that we clarify whether ``task cards,'' as found in
the ``Recording Compliance with Fuel Tank System AWLs'' section of the
original NPRM, means Boeing task cards only or if they also include an
operator's unique task cards.
We intended that ``task cards'' mean both Boeing and an operator's
unique task cards, as applicable. The intent is to address whatever
type of task cards are used by mechanics for maintenance. This AD would
not require any changes to the AMMs or task cards relative to the
CDCCLs. We are only suggesting ways an operator might implement CDCCLs
into its maintenance program. No change to this AD is necessary in this
regard.
Request To Revise Intervals for Certain AWL Inspections
KLM Royal Dutch Airlines (KLM), on behalf of several operators,
requests that we review a 45-page proposal to align certain
airworthiness limitation item (ALI) intervals with the applicable
maintenance significant item (MSI) and enhanced zonal analysis
procedure (EZAP) intervals for Model 737, 747, 757, 767, and 777
airplanes. The recommendations in that proposal ensure that the ALI
intervals align with the maintenance schedules of the operators. Among
other changes, the proposal recommends revising certain AWL inspection
intervals from 16,000 flight cycles/3,000 days to only 6,000 days for
Model 777 airplanes.
We infer that KLM requests we revise paragraph (h) of this AD to
extend the compliance time to 6,000 days for AWLs No. 28-AWL-01 and No.
28-AWL-03. We disagree because we have determined that it would be
inappropriate to extend the inspection intervals. Given the safety
implications for these inspections, 6,000 days (approximately over 16
years) is too long, especially since these areas are accessed more
frequently than every 16 years for maintenance. Also, KLM did not
include any reliability information showing that the systems can
continue to safely operate between the proposed inspection periods.
However, according to the provisions of paragraph (k) of this AD, we
might approve requests to adjust the compliance time if the request
includes data that prove that the new compliance time would provide an
acceptable level of safety. No change to this AD is necessary in this
regard.
Request To Require Latest Revision of the AMM
JAL requests that we revise the original NPRM to require
incorporation of the latest revision of the manufacturer's AMM. JAL
asserts that we have allowed Boeing to include statements in the Boeing
AMM allowing operators to use certain CMM revision levels or later
revisions. JAL states that, with the exception of the CMM, operators
cannot find what revision level of the AMM needs to be incorporated
into the operator's AMM in order to comply with the proposed
requirements of the original NPRM. JAL also states that it could take
several weeks to incorporate the manufacturer's AMM.
JAL further requests that we clarify whether it is acceptable to
change the procedures in the AMM with Boeing's acceptance. JAL states
that the MPD notes that any use of parts, methods, techniques, or
practices not contained in the applicable CDCCL and AWL inspection must
be approved by the FAA office that is responsible for the airplane
model type certificate, or applicable regulatory agency. JAL also
states that the Boeing AMM or CMM notes to obey the manufacturer's
procedures when doing maintenance that affects a CDCCL or AWL
inspection. However, JAL believes that according to the original NPRM
it is acceptable to change the AMM procedures with Boeing's acceptance.
We disagree with the changes proposed by the commenter. This AD
does not require revising the AMM. This AD does require revising your
maintenance program to incorporate the AWLs identified in Revision
February 2008 of the MPD. However, complying with the AWL inspections
or CDCCLs will require other actions by operators including AMM
revisions. In the U.S., operators are not required to use original
equipment manufacturer (OEM) maintenance manuals. Operators may develop
their own manuals, which are reviewed and accepted by the FAA Flight
Standards Service. In order to maintain that flexibility for operators,
all of the AWLs contain all of the critical information, such as
maximum bonding resistances and minimum separation requirements. The
FAA Flight Standards Service will only accept operator manuals that
contain all of the information specified in the AWLs, so there is no
need to require operators to use the OEM maintenance manuals.
Regarding JAL's request for clarification of approval of AWL
changes, we infer JAL is referring to the following sentence located in
the ``Changes to AMMs Referenced in Fuel Tank System AWLs'' section of
the original NPRM: ``A maintenance manual change to these tasks may be
made without approval by the Manager, Seattle ACO, through an
appropriate FAA principal maintenance inspector (PMI) or principal
avionics inspector (PAI), by the governing regulatory authority, or by
using the operator's standard process for revising maintenance
manuals.'' If changes need to be made to tasks associated with an AWL,
they may be made using an operator's normal process without approval of
the Seattle ACO, as long as the change maintains the information
specified in the AWL. For some CDCCLs, it was beneficial to not put all
the critical information into the MPD. This avoids duplication of a
large amount of information. In these cases, the CDCCL refers to a
specific revision of the CMM. U.S. operators are required to use those
CMMs. Any changes to the CMMs must be approved by the Seattle ACO.
Request To Revise AMM Task 28-11-00
The ATA, on behalf of CAL, submitted a comment regarding AWL No.
28-AWL-01, which specifies doing
[[Page 30740]]
repetitive detailed inspections of the wire bundles routed over the
center fuel tank and under the main deck floor boards to detect damaged
clamps, wire chafing, and any wire bundle that is in contact with the
surface of the center fuel tank. The AWL specifies doing the inspection
in accordance with Task 28-11-00 of the Boeing 777 AMM. CAL states
that, according to the definition for a detailed inspection in the
Enhanced Airworthiness Program for Airplane Systems (EAPAS) Participant
Guide, dated August 2007, a detailed inspection may include a tactile
assessment in which a component or assembly is checked for tightness
and security (to ensure continued integrity of installations such as
bonding jumpers and terminal connectors). CAL states that the
inspection for tightness and security might require the disassembly of
the wire installation, but that there are no re-installation procedures
in the current routine manuals. CAL also states that maintenance
personnel have to disassemble the entire wire bundle installation to
accomplish the detailed inspection in Task 28-11-00-210-801 of the
Boeing 777 AMM. According to CAL, this action, in the past, has created
more discrepancies with wire bundle installations.
We infer the commenters request that Boeing revise Task 28-11-00 of
the Boeing 777 AMM to include procedures for re-installation of the
wire bundles. We do not agree that the Boeing 777 AMM needs to be
revised. This inspection does not require any disassembly of wire
bundle installations because, as CAL points out, disassembly might
create an unsafe condition. The guidance for a detailed inspection
provided by the Maintenance Steering Group 3 (MSG-3) and EAPAS includes
a tactile assessment of bundle security, which uses the mechanic's
hands to pull on the bundle. A visual inspection is not sufficient. The
tactile assessment is intended to be a non-intrusive inspection. No
change to this AD is necessary in this regard.
Request To Revise AMM Task 28-11-00-210-801
The ATA, on behalf of CAL, submitted a comment regarding Task 28-
11-00-210-801 of the Boeing 777 AMM for accomplishing a detailed
inspection of the wire bundles between the main deck and the top
surface of the center fuel tank. (Task 28-11-00 is referenced in AWL
No. 28-AWL-01 of Revision February 2008 of the MPD.) CAL states that
the task procedures do not provide specific details or information for
the wire bundle installation to ensure that maintenance personnel can
comply with the design requirements. CAL also states that the wire
bundle installation has been modified according to Boeing Alert Service
Bulletin 777-57A0050, dated January 26, 2006; and Boeing Alert Service
Bulletin 777-57A0051, dated May 15, 2006. CAL states that it provided
comments to the NPRM that propose to mandate the accomplishment of
those service bulletins. (That NPRM (Docket No. FAA-2007-27042) was
published in the Federal Register on January 29, 2007 (72 FR 3956).)
We infer the commenters request that Boeing revise Task 28-11-00-
210-801 of the Boeing 777 AMM to provide specific details for the wire
bundle installation. We do not agree that the Boeing 777 AMM needs to
be revised because specific design information is not needed for
accomplishing this inspection. The type and location of the wiring over
the center fuel tank can vary among airplanes, and these details are
not necessary to complete the inspection. AWL No. 28-AWL-01 is
concerned with wire installation failures that will eventually lead to
arcing through the top surface of the tank. That AWL and the referenced
AMM provide for the type of failures that might progress to arcing, and
any wire bundle in that area needs to be inspected. No change to this
AD is necessary in this regard.
Request To Revise AMM by Including Warning Statements
The ATA, on behalf of CAL, submitted a comment regarding Tasks 28-
11-00-210-801 and 05-55-54-200-801 of the Boeing 777 AMM. CAL states
that these tasks do not contain CDCCL warning statements to alert
maintenance personnel of their importance to regulatory compliance
requirements.
We infer the commenters request that Boeing revise the Boeing 777
AMM to include warning statements as stated by CAL. We do not agree
that the Boeing 777 AMM needs to be revised because Step A.(1) of the
relevant AMM sections contains notes about the CDCCLs. The FAA and
Boeing chose to use notes, not warning statements, because we did not
want to undermine other sections of the AMM, which are not tied to AWLs
but are still necessary for maintaining the airplane. If CAL determines
that a different approach would work better for its maintenance
program, it can develop a different system with the help of its PMI or
PAI. No change to this AD is necessary in this regard.
Request To Publish Manuals for Maintenance Personnel
The ATA, on behalf of CAL, submitted a comment stating that CAL is
concerned that not enough attention has been given to ensure that
specific detailed inspections are preserved for the long-term operation
of its Model 777 fleet. CAL states that, other than some generic
information found in Revision October 2007 of the MPD, there are no
published maintenance documents for continuous airworthiness available
to show each specific requirement as detailed in the airplane
production drawings, such as Task 05-55-54-200-801 of the Boeing 777
AMM. CAL further states that information detailed by the airplane
production drawing must be available in manuals that are routinely used
by the maintenance personnel. CAL asserts that making this information
available will prevent the inadvertent reversal of the designated
configuration, which could lead to violation of the supplemental NPRM,
in addition to compromising the higher level of safety intended for the
Model 777 fleet.
CAL believes the current program, as provided by AWLs No. 28-AWL-01
and No. 28-AWL-03 of Revision October 2007 of the MPD, is not ready to
be implemented. CAL states that, if those AWLs are mandated as
proposed, CAL would not be able to incorporate those AWLs in its Model
777 fleet, and a high risk of future de-modification of the wire
bundles would exist for airplanes on which those AWLs could be
implemented. CAL recommends that we coordinate with Boeing regarding
the changes it requests in the previous comments.
We infer the commenters request that we delay issuance of the final
rule until Boeing publishes manual(s) containing detailed information
for maintenance personnel to accomplish the required AWL inspections.
We disagree. To delay this action would be inappropriate, since we have
determined that an unsafe condition exists and that the actions
required by this AD must be mandated to ensure continued safety.
The amount of detail within the Boeing 777 AMM needs to be
balanced, and it might not be the same for every operator. The FAA and
Boeing have worked together to define what design requirements need to
be included in the AMMs for fuel tank ignition prevention features. If
the AMMs are overly specific, they might be too voluminous to be used
effectively and would be prone to errors, since wiring installations
vary among airplanes. The amount of information needed to be
[[Page 30741]]
included in the AMMs will also vary among operators, depending on the
processes and training for a given operator. If CAL determines more
detailed design information needs to be included in its AMMs, CAL can
work with its PMI or PAI and Boeing to add that information. No change
to this AD is necessary in this regard.
Request To Delete Reference to Parts Manufacturer Approval (PMA) Parts
ANA requests that we delete the words ``Any use of parts (including
the use of parts manufacturer approval (PMA) approved parts),'' unless
a continuous supply of CMM-specified parts is warranted or the FAA is
open 24 hours to approve alternative parts for in-house repair by the
operator. Those words are located in the following sentence in the
``Changes to CMMs Cited in Fuel Tank System AWLs'' section of the
original NPRM: ``Any use of parts (including the use of parts
manufacturer approval (PMA) approved parts), methods, techniques, and
practices not contained in the CMMs needs to be approved by the
Manager, Seattle ACO, or governing regulatory authority.''
ANA states that in some cases the parts specified in the CMMs
cannot be obtained from the parts market or directly from the component
vendor, so an operator is forced into using alternative parts to keep
its schedule. ANA requests that we direct the component vendor to
ensure a continuous supply of CMM parts and to direct the component
vendor to remedy a lack of parts if parts are not promptly supplied.
ANA further requests that we direct the component vendor to promptly
review the standard parts and allow use of alternative fasteners and
washers listed in Boeing D590. ANA asserts that, in some cases, a
component vendor specifies the uncommon part to preserve its monopoly.
We disagree with revising the ``Changes to CMMs Cited in Fuel Tank
System AWLs'' section of the original NPRM. We make every effort to
identify potential problems with the parts supply, and we are not aware
of any problems at this time. The impetus to declare overhaul and
repair of certain fuel tank system components as CDCCLs arose from in-
service pump failures that resulted from repairs not done according to
OEM procedures. We have approved the use of the CMMs--including parts,
methods, techniques, and practices--at the revision levels specified in
Revision February 2008 of the MPD. Third-party spare parts, such as
parts approved by PMA, have not been reviewed. We expect that such
parts might be found to be acceptable alternatives.
An operator may submit a request to the Seattle ACO, or governing
regulatory authority, for approval of an AMOC if sufficient data are
submitted to substantiate that use of an alternative part would provide
an acceptable level of safety. The CDCCLs do not restrict where repairs
can be performed, so an operator may do the work in-house as long as
the approved CMMs are followed. If operators would like to change those
procedures, they can request approval of the changes. The FAA makes
every effort to respond to operators' requests in a timely manner. If
there is a potential for disrupting the flight schedule, the operator
should include that information in its request. Operators should
request approval for the use of PMA parts and alternative procedures
from the FAA or the governing regulatory authority in advance in order
to limit schedule disruptions. We have not changed this AD in this
regard.
Request To Identify Other Test Equipment
JAL states that certain test equipment is designated in the MPD and
that additional equipment should also be designated. For example, AWL
No. 28-AWL-03 would require using loop resistance tester, part number
(P/N) 906-10246-2 or -3. Therefore, JAL requests that we also identify
alternative test equipment, so that operators do not need to seek an
AMOC to use other equipment.
We disagree with identifying other test equipment. We cannot
identify every possible piece of test equipment. We ensure that some
are listed as recommended by the manufacturer. With substantiating
data, operators can request approval of an alternative tester from the
Seattle ACO, or the governing regulatory agency. We have not changed
this AD in this regard.
Request To Clarify AWL No. 28-AWL-02
JAL requests that we clarify the intent of AWL No. 28-AWL-02. JAL
states that Chapters 53-01 and 53-21 of the Boeing 777 AMM specify
doing an inspection of the external wires over the center fuel tank
according to AMM 28-11-00 before installing the floor panel over the
center wing tank based on AWL No. 28-AWL-02. JAL also states that,
according to Revision March 2006 of the MPD, AWL No. 28-AWL-02 contains
two limitations: Maintaining the existing wire bundle routing and
clamping, and installing any new wire bundle per the Boeing standard
wiring practices manual (SWPM). Therefore, JAL believes it is not
necessary to inspect the external wires over the center fuel tank
according to AMM 28-11-00 before installing the floor panel over the
center wing tank, unless that wire bundle routing and clamping are
changed.
We point out that AWL No. 28-AWL-02 also contains a third
limitation: Verifying that all wire bundles over the center fuel tank
are inspected according to AWL No. 28-AWL-01, which refers to AMM 28-
11-00 for accomplishing the inspection. We do not agree that the
inspection should be required only if the wire bundle routing and
clamping are changed while maintenance is accomplished in the area. If
any of the other bundles have a clamp or routing failure, it must be
detected and corrected. After accomplishing the inspection required by
AWL No. 28-AWL-01, an operator would not need to repeat the inspection
for another 16,000 flight cycles or 3,000 days, whichever is first. No
change to this AD is necessary in this regard.
Request for Clarification for Recording Compliance With CDCCLs
JAL requests that we clarify the following sentence: ``An entry
into an operator's existing maintenance record system for corrective
action is sufficient for recording compliance with CDCCLs, as long as
the applicable maintenance manual and task cards identify actions that
are CDCCLs.'' That sentence is located in the ``Recording Compliance
with Fuel Tank System AWLs'' section of the original NPRM.
Specifically, JAL asks whether an operator must indicate the CDCCL in
their recording documents or whether it is sufficient for the recording
document to call out the applicable AMMs that are tied to the CDCCLs.
We have coordinated with the FAA Flight Standards Service and it
agrees that, for U.S.-registered airplanes, if the applicable AMMs and
task cards identify the CDCCL, then the entry into the recording
documents does not need to identify the CDCCL. However, if the
applicable AMMs and tasks cards do not identify the CDCCL, then they
must be identified. Other methods may be accepted by the appropriate
FAA PMI or PAI, or governing regulatory authority. No change to this AD
is necessary in this regard.
Request To Clarify Approval of CMM Changes
JAL requests that we clarify whether FAA approval is required for
changes to the CMM. JAL states that, when it finds incorrect
instructions, typographical
[[Page 30742]]
errors, or vague instructions in the CMM, it usually contacts the
component manufacturer about those issues and revises the instructions
in its own manuals. JAL states that those changes are not reflected in
the CMM until the component manufacturer revises the CMM. JAL requests
that we provide guidelines for CMM errors that do not require FAA
approval.
Changes to the CMMs must be approved by the FAA, or governing
regulatory authority, before the revised CMMs can be used. No change to
this AD is necessary in this regard.
Conclusion
We have carefully reviewed the available data, including the
comments received, and determined that air safety and the public
interest require adopting the AD with the changes described previously.
We have determined that these changes will neither increase the
economic burden on any operator nor increase the scope of the AD.
Costs of Compliance
We estimate that this AD affects 127 airplanes of U.S. registry.
The following table provides the estimated costs, at an average labor
rate of $80 per work hour, for U.S. operators to comply with this AD.
Estimated Costs
----------------------------------------------------------------------------------------------------------------
Number of
Cost per U.S.-
Action Work hours Parts airplane registered Fleet cost
airplanes
----------------------------------------------------------------------------------------------------------------
AWLs revision....................... 8 None.................. $640 127 $81,280
Inspection.......................... 8 None.................. 640 127 81,280
----------------------------------------------------------------------------------------------------------------
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 AD will not have federalism
implications under Executive Order 13132. This AD 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.
For the reasons discussed above, I certify that this AD:
(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.
We prepared a regulatory evaluation of the estimated costs to
comply with this 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.
Adoption of the Amendment
0
Accordingly, under the authority delegated to me by the Administrator,
the FAA amends 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. The Federal Aviation Administration (FAA) amends Sec. 39.13 by
adding the following new airworthiness directive (AD):
2008-11-13 Boeing: Amendment 39-15536. Docket No. FAA-2007-28389;
Directorate Identifier 2006-NM-171-AD.
Effective Date
(a) This AD becomes effective July 3, 2008.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Boeing Model 777-200, -200LR, -300, and -
300ER series airplanes; certificated in any category; with an
original standard airworthiness certificate or original export
certificate of airworthiness issued before December 5, 2007.
Note 1: Airplanes with an original standard airworthiness
certificate or original export certificate of airworthiness issued
on or after December 5, 2007, must be already in compliance with the
airworthiness limitations (AWLs) specified in this AD because those
limitations were applicable as part of the airworthiness
certification of those airplanes.
Note 2: This AD requires revisions to certain operator
maintenance documents to include new inspections. Compliance with
these inspections is required by 14 CFR 91.403(c). For airplanes
that have been previously modified, altered, or repaired in the
areas addressed by these inspections, the operator may not be able
to accomplish the inspections described in the revisions. In this
situation, to comply with 14 CFR 91.403(c), the operator must
request approval for an alternative method of compliance (AMOC)
according to paragraph (k) of this AD. The request should include a
description of changes to the required inspections that will ensure
the continued operational safety of the airplane.
Unsafe Condition
(d) This AD results from a design review of the fuel tank
systems. We are issuing this AD to prevent the potential for
ignition sources inside fuel tanks caused by latent failures,
alterations, repairs, or maintenance actions, which, in combination
with flammable fuel vapors, could result in fuel tank explosions and
consequent loss of the airplane.
Compliance
(e) Comply with this AD within the compliance times specified,
unless already done.
Service Information
(f) The term ``Revision February 2008 of the MPD,'' as used in
this AD, means Boeing Temporary Revision (TR) 09-014, dated December
2007. Boeing TR 09-014 is published as Section 9 of the Boeing 777
Maintenance Planning Document (MPD) D622W001-9, Revision February
2008.
[[Page 30743]]
Revision of Airworthiness Limitations (AWLs) Section
(g) Before December 16, 2008, revise the AWLs section of the
Instructions for Continued Airworthiness (ICA) by incorporating the
information in the subsections specified in paragraphs (g)(1) and
(g)(2) of this AD; except that the initial inspections specified in
paragraph (h) of this AD must be done at the compliance times
specified in paragraph (h) of this AD.
(1) Subsection D, ``AIRWORTHINESS LIMITATIONS--SYSTEMS,'' of
Revision February 2008 of the MPD.
(2) Subsection E, ``PAGE FORMAT: FUEL SYSTEMS AIRWORTHINESS
LIMITATIONS,'' AWLs No. 28-AWL-01 through No. 28-AWL-20 inclusive,
of Revision February 2008 of the MPD. As an optional action, AWLs
No. 28-AWL-21 through No. 28-AWL-26 inclusive, as identified in
Subsection E of Revision February 2008 of the MPD, also may be
incorporated into the AWLs section of the ICA.
Initial Inspections and Repair
(h) Do the inspections required by paragraphs (h)(1) and (h)(2)
of this AD at the compliance times specified in paragraphs (h)(1)
and (h)(2), in accordance with the applicable AWLs described in
Subsection E of Revision February 2008 of the MPD. If any
discrepancy is found during these inspections, repair the
discrepancy before further flight in accordance with Revision
February 2008 of the MPD.
(1) At the later of the times specified in paragraphs (h)(1)(i)
and (h)(1)(ii) of this AD, do a detailed inspection of external
wires over the center fuel tank for damaged clamps, wire chafing,
and wire bundles in contact with the surface of the center fuel
tank, and repair any discrepancy, in accordance with AWL No. 28-AWL-
01. Accomplishing AWL No. 28-AWL-01 as part of an FAA-approved
maintenance program before the applicable compliance time specified
in paragraph (h)(1)(i) or (h)(1)(ii) of this AD constitutes
compliance with the requirements of this paragraph.
(i) Before the accumulation of 16,000 total flight cycles, or
within 3,000 days since the date of issuance of the original
standard airworthiness certificate or the date of issuance of the
original export certificate of airworthiness, whichever occurs
first.
(ii) Within 72 months after the effective date of this AD.
Note 3: 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.''
(2) At the later of the times specified in paragraphs (h)(2)(i)
and (h)(2)(ii) of this AD, do a special detailed inspection
(resistance test) of the lightning shield-to-ground termination of
the out tank wiring of the fuel quantity indicating system (FQIS)
and, as applicable, repair (restore) the bond to ensure the shield-
to-ground termination meets specified resistance values, in
accordance with AWL No. 28-AWL-03. Accomplishing AWL No. 28-AWL-03
as part of an FAA-approved maintenance program before the applicable
compliance time specified in paragraph (h)(2)(i) or (h)(2)(ii) of
this AD constitutes compliance with the requirements of this
paragraph.
(i) Before the accumulation of 16,000 total flight cycles, or
within 3,000 days since the date of issuance of the original
standard airworthiness certificate or the date of issuance of the
original export certificate of airworthiness, whichever occurs
first.
(ii) Within 24 months after the effective date of this AD.
Note 4: For the purposes of this AD, a special detailed
inspection is: ``An intensive examination of a specific item,
installation, or assembly to detect damage, failure, or
irregularity. The examination is likely to make extensive use of
specialized inspection techniques and/or equipment. Intricate
cleaning and substantial access or disassembly procedure may be
required.''
No Alternative Inspections, Inspection Intervals, or Critical Design
Configuration Control Limitations (CDCCLs)
(i) After accomplishing the actions specified in paragraphs (g)
and (h) of this AD, no alternative inspections, inspection
intervals, or CDCCLs may be used unless the inspections, intervals,
or CDCCLs are part of a later revision of Revision February 2008 of
the MPD that is approved by the Manager, Seattle Aircraft
Certification Office (ACO); or unless the inspections, intervals, or
CDCCLs are approved as an AMOC in accordance with the procedures
specified in paragraph (k) of this AD.
Credit for Actions Done According to Previous Revisions of the MPD
(j) Actions done before the effective date of this AD in
accordance with Section 9 of the Boeing 777 MPD Document, D622W001-
9, Revision October 2007; or Revision December 2007; are acceptable
for compliance with the corresponding requirements of paragraphs (g)
and (h) of this AD.
Alternative Methods of Compliance (AMOCs)
(k)(1) The Manager, Seattle ACO, FAA, ATTN: Margaret Langsted,
Aerospace Engineer, Propulsion Branch, ANM-140S, 1601 Lind Avenue,
SW., Renton, Washington 98057-3356; telephone (425) 917-6500; fax
(425) 917-6590; has the authority to approve AMOCs for this AD, if
requested using the procedures found in 14 CFR 39.19.
(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 appropriate principal inspector (PI) in the FAA
Flight Standards District Office (FSDO), or lacking a PI, your local
FSDO.
Material Incorporated by Reference
(l) You must use Boeing Temporary Revision (TR) 09-014, dated
December 2007, to the Boeing 777 Maintenance Planning Document (MPD)
Document, D622W001-9, to do the actions required by this AD, unless
the AD specifies otherwise. Boeing TR 09-014 is published as Section
9 of the Boeing 777 Maintenance Planning Document (MPD) Document,
D622W001-9, Revision February 2008. (The List of Effective Pages for
Section 9 of Boeing 777 Maintenance Planning Document (MPD)
Document, D622W001-9, Revision February 2008, contains numerous
errors. However, the revision/date identified on the individual
pages of the document are correct.)
(1) The Director of the Federal Register approved the
incorporation by reference of this service information under 5
U.S.C. 552(a) and 1 CFR part 51.
(2) For service information identified in this AD, contact
Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington
98124-2207.
(3) You may review copies of the service information
incorporated by reference 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: <a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.
Issued in Renton, Washington, on May 14, 2008.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E8-11467 Filed 5-28-08; 8:45 am]
BILLING CODE 4910-13-P
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