[Federal Register: July 6, 2007 (Volume 72, Number 129)]
[Proposed Rules]
[Page 36901-36905]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr06jy07-18]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2007-28382; Directorate Identifier 2006-NM-179-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 727 Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for all Boeing Model 727 airplanes. This proposed AD would require
revising the FAA-approved maintenance program by incorporating new
airworthiness limitations (AWLs) for fuel tank systems to satisfy
Special Federal Aviation Regulation No. 88 requirements. This proposed
AD would also require the initial inspection of a certain repetitive
AWL inspection to phase in that inspection, and repair if necessary.
This proposed AD results from a design review of the fuel tank systems.
We are proposing 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 a fuel tank explosion and consequent loss of the
airplane.
DATES: We must receive comments on this proposed AD by August 20, 2007.
ADDRESSES: Use one of the following addresses to submit comments on
this proposed AD.
DOT Docket Web site: Go to http://dms.dot.gov and follow
the instructions for sending your comments electronically.
Government-wide rulemaking Web site: Go to http://www.regulations.gov
and follow the instructions for sending your
comments electronically.
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.
Fax: (202) 493-2251.
Hand Delivery: Room W12-140 on the ground floor of the
West Building, 1200 New Jersey Avenue, SE., Washington, DC, between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle,
Washington 98124-2207, for the service information identified in this
proposed AD.
FOR FURTHER INFORMATION CONTACT: Kathrine Rask, Aerospace Engineer,
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification
Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone
(425) 917-6505; fax (425) 917-6590.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to submit any relevant written data, views, or
arguments regarding this proposed AD. Send your comments to an address
listed in the ADDRESSES section. Include the docket number ``FAA-2007-
28382; Directorate Identifier 2006-NM-179-AD'' at the beginning of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of the proposed AD. We will
consider all comments received by the closing date and may amend the
proposed AD in light of those comments.
We will post all comments we receive, without change, to http://dms.dot.gov
, including any personal information you provide. We will
also post a report summarizing each substantive verbal contact with FAA
personnel concerning this proposed AD. Using the search function of
that Web site, anyone can find and read the comments in any of our
dockets,
[[Page 36902]]
including the name of the individual who sent the comment (or signed
the comment on behalf of an association, business, labor union, etc.).
You may review DOT's complete Privacy Act Statement in the Federal
Register published on April 11, 2000 (65 FR 19477-78), or you may visit
http://dms.dot.gov.
Examining the Docket
You may examine the AD docket on the Internet at http://dms.dot.gov
, or in person at the Docket Operations office between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays. The
Docket Operations office (telephone (800) 647-5527) is located on the
ground floor of the West Building at the DOT street address stated in
the ADDRESSES section. Comments will be available in the AD docket
shortly after the Docket Management System receives them.
Discussion
The FAA has examined the underlying safety issues involved in fuel
tank explosions on several large transport airplanes, including the
adequacy of existing regulations, the service history of airplanes
subject to those regulations, and existing maintenance practices for
fuel tank systems. As a result of those findings, we issued a
regulation titled ``Transport Airplane Fuel Tank System Design Review,
Flammability Reduction and Maintenance and Inspection Requirements''
(67 FR 23086, May 7, 2001). In addition to new airworthiness standards
for transport airplanes and new maintenance requirements, this rule
included Special Federal Aviation Regulation No. 88 (``SFAR 88,''
Amendment 21-78, and subsequent Amendments 21-82 and 21-83).
Among other actions, SFAR 88 requires certain type design (i.e.,
type certificate (TC) and supplemental type certificate (STC)) holders
to substantiate that their fuel tank systems can prevent ignition
sources in the fuel tanks. This requirement applies to type design
holders for large turbine-powered transport airplanes and for
subsequent modifications to those airplanes. It requires them to
perform design reviews and to develop design changes and maintenance
procedures if their designs do not meet the new fuel tank safety
standards. As explained in the preamble to the rule, we intended to
adopt airworthiness directives to mandate any changes found necessary
to address unsafe conditions identified as a result of these reviews.
In evaluating these design reviews, we have established four
criteria intended to define the unsafe conditions associated with fuel
tank systems that require corrective actions. The percentage of
operating time during which fuel tanks are exposed to flammable
conditions is one of these criteria. The other three criteria address
the failure types under evaluation: single failures, single failures in
combination with another latent condition(s), and in-service failure
experience. For all four criteria, the evaluations included
consideration of previous actions taken that may mitigate the need for
further action.
We have determined that the actions identified in this proposed AD
are necessary to reduce the potential of ignition sources inside fuel
tanks, which, in combination with flammable fuel vapors, could result
in a fuel tank explosion and consequent loss of the airplane.
Relevant Service Information
We have reviewed the following sections of Boeing 727-100/200
Airworthiness Limitations (AWLs), D6-8766-AWL, original release, dated
March 2006 (hereafter referred to as ``Document D6-8766-AWL''), for
Model 727, 727C, 727-100, 727-100C, 727-200, and 727-200F series
airplanes:
Section A, ``SCOPE''
Section B, ``FUEL SYSTEMS AIRWORTHINESS LIMITATIONS''
Section C, ``SYSTEM AWL PAGE FORMAT''
Section D, ``AIRWORTHINESS LIMITATIONS--FUEL SYSTEMS''
Those sections of Document D6-8766-AWL describe new AWLs for fuel tank
systems. The new AWLs include:
AWL inspections, which are periodic inspections of certain
features for latent failures that could contribute to an ignition
source; and
Critical design configuration control limitations
(CDCCLs), which are limitation requirements to preserve a critical
ignition source prevention feature of the fuel tank system design that
is necessary to prevent the occurrence of an unsafe condition. The
purpose of a CDCCL is to provide instruction to retain the critical
ignition source prevention feature during configuration change that may
be caused by alterations, repairs, or maintenance actions. A CDCCL is
not a periodic inspection.
Accomplishing the actions specified in the service information is
intended to adequately address the unsafe condition.
FAA's Determination and Requirements of the Proposed AD
We have evaluated all pertinent information and identified an
unsafe condition that is likely to exist or develop on other airplanes
of this same type design. For this reason, we are proposing this AD,
which would require the FAA-approved maintenance program by
incorporating the information in Sections A, B, C, and D of Document
D6-8766-AWL. This proposed AD would also require the initial inspection
of a certain repetitive AWL inspection to phase in that inspection, and
repair if necessary.
Difference Between Proposed AD and Service Bulletin
In most ADs, we adopt a compliance time allowing a specified amount
of time after the AD's effective date. In this case, however, the FAA
has already issued regulations that require operators to revise their
maintenance/inspection programs to address fuel tank safety issues. The
compliance date for these regulations is December 16, 2008. To provide
for efficient and coordinated implementation of these regulations and
this proposed AD, we are using this same compliance date in this
proposed AD, instead of the 18-month compliance time recommended in the
service bulletin.
Rework Required When Implementing AWLs Into an Existing Fleet
The maintenance program revision for the fuel tank systems
specified in paragraph (g) of this proposed AD, which involves
incorporating the information specified in Document D6-8766-AWL, would
affect how operators maintain their airplanes. After doing that
maintenance program revision, operators would need to do any
maintenance on the fuel tank system as specified in the CDCCLs.
Maintenance done before the maintenance program revision specified in
paragraph (g) would not need to be redone in order to comply with
paragraph (g). For example, the AWL that requires fuel pumps to be
repaired and overhauled per an FAA-approved component maintenance
manual (CMM) applies to fuel pumps repaired after the maintenance
programs are revised; spare or on-wing fuel pumps do not need to be
reworked. For AWLs that require repetitive inspections, the initial
inspection interval (threshold) starts from the date the maintenance
program revision specified in paragraph (g) is done, except as provided
by paragraph (h) of this proposed AD. This proposed AD would require
only the maintenance
[[Page 36903]]
program revision specified in paragraph (g), and initial inspections
specified in paragraph (h). No other fleet-wide inspections need to be
done.
Changes to Fuel Tank System AWLs
Paragraph (g) of this proposed AD would require revising the FAA-
approved maintenance program by incorporating certain information
specified in Document D6-8766-AWL. Paragraph (g) allows accomplishing
the maintenance program revision in accordance with later revisions of
the Document D6-8766-AWL as an acceptable method of compliance if they
are approved by the Manager, Seattle Aircraft Certification Office
(ACO), FAA. Paragraph (h) allows accomplishing the initial inspection
and repair in accordance with later revisions of Document D6-8766-AWL
as an acceptable method of compliance if they are approved by the
Manager, Seattle ACO. In addition, Section B of Document D6-8766-AWL
specifies that any deviations from the published AWL instructions,
including AWL intervals, must be approved by the Manager, Seattle ACO.
Therefore, after the maintenance program revision, any further revision
to an AWL or AWL interval should be done as an AWL change, not as an
alternative method of compliance (AMOC). For U.S.-registered airplanes,
operators must make requests through an appropriate FAA Principal
Maintenance Inspector (PMI) or Principal Avionics Inspector (PAI) for
approval by the Manager, Seattle ACO. A non-U.S. operator should
coordinate changes with its governing regulatory agency.
Exceptional Short-Term Extensions
Section B of Document D6-8766-AWL has provisions for an exceptional
short-term extension of 30 days. An exceptional short-term extension is
an increase in an AWL interval that may be needed to cover an
uncontrollable or unexpected situation. For U.S.-registered airplanes,
the FAA PMI or PAI must concur with any exceptional short-term
extension before it is used, unless the operator has identified another
appropriate procedure with the local regulatory authority. The FAA PMI
or PAI may grant the exceptional short-term extensions described in
Section B without consultation with the Manager, Seattle ACO. A non-
U.S. operator should coordinate changes with its governing regulatory
agency. As explained in Document D6-8766-AWL, exceptional short-term
extensions must not be used for fleet AWL extensions. An exceptional
short-term extension should not be confused with an operator's short-
term escalation authorization approved in accordance with the
Operations Specifications or the operator's reliability program.
Ensuring Compliance With Fuel Tank System AWLs
Boeing has revised applicable maintenance manuals and task cards to
address AWLs and to include notes about CDCCLs. 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. Appendix 1 of this
proposed AD contains a list of Air Transport Association (ATA) sections
for the revised maintenance manuals. Operators might wish to use the
appendix as an aid to implement the AWLs.
Recording Compliance With Fuel Tank System AWLs
The applicable operating rules of the Federal Aviation Regulations
(14 CFR parts 91, 121, 125, and 129) require operators to maintain
records with the identification of the current inspection status of an
airplane. Some of the AWLs contained in Section D of Document D6-8766-
AWL are inspections for which the applicable sections of the operating
rules apply. Other AWLs are CDCCLs, which are tied to conditional
maintenance actions. 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.
Changes to CMMs Cited in Fuel Tank System AWLs
Some of the AWLs in Section D of Document D6-8766-AWL refer to
specific revision levels of the CMMs as additional sources of service
information for doing the AWLs. Boeing is referring to the CMMs by
revision level in the applicable AWL for certain components rather than
including information directly in Document D6-8766-AWL because of the
volume of that information. As a result, the Manager, Seattle ACO, must
approve the CMMs. Any later revision of those CMMs will be handled like
a change to the AWL itself. Any use of parts (including the use of
parts manufacturer approval (PMA) approved parts), methods, techniques,
and practices not contained in the CMMs need to be approved by the
Manager, Seattle ACO, or governing regulatory authority. For example,
pump repair/overhaul manuals must be approved by the Manager, Seattle
ACO.
Changes to AMMs Referenced in Fuel Tank System AWLs
In other AWLs in Section D of Document D6-8766-AWL, the AWLs
contain all the necessary data. The applicable section of the
maintenance manual is usually included in the AWLs. Boeing intended
this information to assist operators in maintaining the maintenance
manuals. A maintenance manual change to these tasks may be made without
approval by the Manager, Seattle ACO, through an appropriate FAA PMI or
PAI, by the governing regulatory authority, or by using the operator's
standard process for revising maintenance manuals. An acceptable change
would have to maintain the information specified in the AWL such as the
pass/fail criteria or special test equipment.
Costs of Compliance
There are about 530 airplanes of the affected design in the
worldwide fleet. The following table provides the estimated costs, at
an average labor rate of $80 per hour, for U.S. operators to comply
with this proposed AD.
Estimated Costs
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Number of
Cost per U.S.-
Action Work hours Parts airplane registered Fleet cost
airplanes
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Maintenance program revision........ 8 None.................. $640 272 $174,080
Inspection.......................... 8 None.................. 640 272 174,080
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[[Page 36904]]
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, 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.
Sec. 39.13 [Amended]
2. The Federal Aviation Administration (FAA) amends Sec. 39.13 by
adding the following new airworthiness directive (AD):
Boeing: Docket No. FAA-2007-28382; Directorate Identifier 2006-NM-
179-AD.
Comments Due Date
(a) The FAA must receive comments on this AD action by August
20, 2007.
Affected ADs
(b) None.
Applicability
(c) This AD applies to all Boeing Model 727, 727C, 727-100, 727-
100C, 727-200, and 727-200F series airplanes, certificated in any
category.
Note 1: This AD requires revisions to certain operator
maintenance documents to include new inspections and maintenance
actions. Compliance with these limitations is required by 14 CFR
43.16 and 91.403(c). For airplanes that have been previously
modified, altered, or repaired in the areas addressed by these
limitations, the operator may not be able to accomplish the actions
described in the revisions. In this situation, to comply with 14 CFR
43.16 and 91.403(c), the operator must request approval for revision
to the airworthiness limitations in the Boeing 727-100/200
Airworthiness Limitations (AWLs), D6-8766-AWL, according to
paragraph (g) or (i) of this AD, as applicable.
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 a fuel tank explosion
and consequent loss of the airplane.
Compliance
(e) You are responsible for having the actions required by this
AD performed within the compliance times specified, unless the
actions have already been done.
Service Information Reference
(f) The term ``Document D6-8766-AWL'' as used in this AD, means
Boeing 727-100/200 Airworthiness Limitations (AWLs), D6-8766-AWL,
original release, dated March 2006.
Maintenance Program Revision
(g) Before December 16, 2008, revise the FAA-approved
maintenance program to incorporate the information in the sections
specified in paragraphs (g)(1), (g)(2), (g)(3), and (g)(4) of this
AD; except that the initial inspection required by paragraph (h) of
this AD must be done at the applicable compliance time specified in
that paragraph. Accomplishing the revision in accordance with a
later revision of Document D6-8766-AWL is an acceptable method of
compliance if the revision is approved by the Manager, Seattle
Aircraft Certification Office (ACO), FAA.
(1) Section A, ``SCOPE'' of Document D6-8766-AWL.
(2) Section B, ``FUEL SYSTEMS AIRWORTHINESS LIMITATIONS,'' of
Document D6-8766-AWL.
(3) Section C, ``SYSTEM AWL PAGE FORMAT,'' of Document D6-8766-
AWL.
(4) Section D, ``AIRWORTHINESS LIMITATIONS--FUEL SYSTEMS,'' of
Document D6-8766-AWL.
Initial Inspection and Repair if Necessary
(h) At the later of the compliance times specified in paragraphs
(h)(1) and (h)(2) of this AD, do a detailed inspection of the wire
bundles routed over the center fuel tank for damaged clamps, wire
chafing, and wire bundles in contact with the surface of the center
fuel tank, in accordance with AWL Number 28-AWL-01 of Section D of
Document D6-8766-AWL. If any discrepancy is found during the
inspection, repair the discrepancy before further flight in
accordance with AWL Number 28-AWL-01 of Section D of Document D6-
8766-AWL. Accomplishing the actions required by this paragraph in
accordance with a later revision of Document D6-8766-AWL is an
acceptable method of compliance if the revision is approved by the
Manager, Seattle ACO.
Note 2: 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.''
(1) Prior to the accumulation of 36,000 total flight hours, or
within 120 months since the date of issuance of the original
standard airworthiness certification or the date of issuance of the
original export certificate of airworthiness, whichever ever occurs
first.
(2) Within 72 months after the effective date of this AD.
Alternative Methods of Compliance (AMOCs)
(i)(1) The Manager, Seattle ACO, has the authority to approve
AMOCs for this AD, if requested in accordance with the procedures
found in 14 CFR 39.19.
(2) 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.
[[Page 36905]]
Appendix 1.--Implementing Fuel Tank System Airworthiness Limitations on Model 727, 727C, 727-100, 727-100C, 727-
200, 727-200F Series Airplanes
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ATA section or CMM
AWL No. ALI/CDCCL document Task title
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28-AWL-01......................... ALI.................. AMM 28-11-00/601.......... External Wires Over the
Tank No. 2 Inspection.
28-AWL-02......................... CDCCL................ SWPM 20-10-11............. Wiring Assembly and
Installation
Configuration.
28-AWL-03......................... CDCCL................ SWPM 20-10-11............. Wiring Assembly and
Installation
Configuration.
28-AWL-04......................... CDCCL................ CMM 28-41-01, Revision 12;
CMM 28-41-02, Revision 5;
CMM 28-41-03, Revision 3;
CMM 28-41-06, Revision 8;
CMM 28-41-07, Revision
17; CMM 28-41-08,
Revision 9; CMM 28-41-09,
Revision 8; CMM 28-41-23,
Revision 10; or
subsequent revisions.
28-AWL-05......................... CDCCL................ CMM 28-40-03, Revision 5;
CMM 28-41-06, Revision 8;
or subsequent revisions.
28-AWL-06......................... CDCCL................ SWPM 20-14-12............. Repair of Fuel Quantity
Indicator System (FQIS)
Wire Harness.
AMM 28-41-21/401 Remove/Install Fuel Tank
Bulkhead (Spar)
Receptacle Wire Harness.
28-AWL-07......................... CDCCL................ AMM 29-11-53/401.......... Install System A
Hydraulic Fluid Heat
Exchanger.
AMM 29-12-61/401 Install System B
Hydraulic Fluid Heat
Exchanger.
28-AWL-08......................... CDCCL................
28-AWL-09......................... CDCCL................ CMM 28-20-1, Revision 7;
CMM 28-20-5, Revision 6;
CMM 28-20-06, Revision 6;
or subsequent revisions.
28-AWL-10......................... CDCCL................ AMM 28-22-21/401.......... Install Fuel Boost Pump.
28-AWL-11......................... CDCCL................ AMM 28-21-93/401.......... Remove the Auxiliary Tank
Fueling Float Switch.
AMM 28-21-93/401 Install the Auxiliary
Tank Fueling Float
Switch.
28-AWL-12......................... CDCCL................ AMM 28-11-21/401.......... Removal/Installation Cast
Fuel Tank Access Panels.
28-AWL-13......................... CDCCL................ AMM 28-11-21/401.......... Removal/Installation
Machined Fuel Tank
Access Panels.
AMM 28-13-11/401 Install the Relief Valve.
28-AWL-14......................... CDCCL................ AMM 28-22-21/601.......... Fuel Boost Pump--
Inspection/Check.
28-AWL-15......................... CDCCL................ AMM 28-22-00/101.......... Engine Fuel Feed System--
Trouble Shooting.
----------------------------------------------------------------------------------------------------------------
Issued in Renton, Washington, on June 22, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E7-13115 Filed 7-5-07; 8:45 am]
BILLING CODE 4910-13-P