

[Federal Register: September 11, 2007 (Volume 72, Number 175)]
[Proposed Rules]               
[Page 51725-51728]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr11se07-14]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-29173; Directorate Identifier 2006-NM-283-AD]
RIN 2120-AA64

 
Airworthiness Directives; Boeing Model 767 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 767 airplanes. This proposed AD would require 
installing an automatic shutoff system for the auxiliary fuel tank 
pump, revising the airplane flight manual (AFM) to advise the flight 
crew of certain operating restrictions for airplanes equipped with an 
automatic auxiliary fuel tank pump shutoff control, revising the 
Airworthiness Limitations (AWLs) section of certain maintenance 
documents to include new inspections of the automatic shutoff system 
for the auxiliary fuel tank boost pumps, and, for certain airplanes, 
installing a placard to alert the flight crew of certain fuel usage 
restrictions. This proposed AD results from a design review of the fuel 
tank systems. We are proposing this AD to prevent an overheat condition 
outside the pump explosion-resistance area that is open to the pump 
inlet, which could cause an ignition source for the fuel vapors in the 
fuel tank and result in fuel tank explosions and consequent loss of the 
airplane.

DATES: We must receive comments on this proposed AD by October 26, 
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: Judy Coyle, Aerospace Engineer, 
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification 
Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone 
(425) 917-6497; 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-
29173; Directorate Identifier 2006-NM-283-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, 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) 647-5227) 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'' 
(66 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

[[Page 51726]]

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 a 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.
    Initial results from the SFAR 88 analysis show that fuel pumps that 
run dry could cause an overheat condition outside the pump explosion-
resistance area that is open to the pump inlet, which could cause an 
ignition source for the fuel vapors in the fuel tank.
    We have determined that the actions identified in this AD are 
necessary to reduce the potential of ignition sources inside fuel 
tanks, which, in combination with flammable fuel vapors, could result 
in fuel tank explosions and consequent loss of the airplane.

Relevant Service Information

    We have reviewed Boeing Alert Service Bulletins 767-28A0083 and 
767-28A0084, both Revision 1, dated April 26, 2007. The service 
bulletins describe procedures for installing an automatic shutoff 
system for the auxiliary fuel tank pump. The actions involve installing 
new relay brackets and relays in the P36 and P37 panels, and, for 
certain airplanes, in the P33 panels; changing the wiring in the 
panels; and installing wiring between the panels.
    We have also reviewed Section 9, ``Airworthiness Limitations (AWLs) 
and Certification Maintenance Requirements (CMRs),'' of Boeing 767 
Maintenance Planning Data (MPD) Document D622T001-9, Revision March 
2006. That revision adds new fuel system Airworthiness Limitations 
Instruction (ALI) 28-AWL-20 to Subsection G, ``AIRWORTHINESS 
LIMITATIONS--FUEL SYSTEM AWLs, of Section 9, which includes periodic 
inspections of the automatic shutoff system for the auxiliary tank fuel 
boost pumps to detect latent failures that could contribute to an 
ignition source. That revision also adds critical design configuration 
control limitation (CDCCL) 28-AWL-19, which includes a post-maintenance 
inspection of certain wiring in the fuel quantity indicating system. 
CDCCLs 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 accomplishing the actions specified in the service 
information described previously. For certain airplanes, this proposed 
AD would also require installing a placard to alert the flight crew of 
certain fuel usage restrictions imposed by AD 2001-15-08. This proposed 
AD would also allow accomplishing the AWL revision in accordance with 
later revisions of the MPD as an acceptable method of compliance if 
they are approved by the Manager, Seattle Aircraft Certification Office 
(ACO), FAA.

Costs of Compliance

    There are about 941 airplanes of the affected design in the 
worldwide fleet; of these, 414 are U.S. registered. The following table 
provides the estimated costs for U.S. operators to comply with this 
proposed AD. The total fleet cost could be as high as $4,655,016.

                                                 Estimated Costs
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                                                                      Average
      Affected airplanes            Affected        Work hours     hourly  labor       Parts         Cost per
                                 airplane groups                       rate                          airplane
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767-200, 767-300, 767-300F....  1-39............              29             $80          $8,924         $11,244
                                40-79...........              25              80           8,495          10,495
                                80-81...........               3              80             420             660
767-400ER.....................  All.............              23              80           7,911           9,751
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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;

[[Page 51727]]

    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-2007-29173; Directorate Identifier 2006-NM-
283-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by October 
26, 2007.

Affected ADs

    (b) Accomplishment of certain requirements of this AD terminates 
certain requirements of AD 2001-15-08, amendment 39-12342.

Applicability

    (c) This AD applies to all Boeing Model 767-200, -300, -300F, 
and -400ER series airplanes, certificated in any category.

Unsafe Condition

    (d) This AD results from a design review of the fuel tank 
systems. We are issuing this AD to prevent an overheat condition 
outside the pump explosion-resistance area that is open to the pump 
inlet, which could cause an ignition source for the fuel vapors in 
the fuel tank and result in fuel tank explosions 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.

    Note 1: 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 according 
to paragraph (m) of this AD.

Installation

    (f) Within 36 months after the effective date of this AD, 
install an automatic shutoff system for the auxiliary fuel tank 
pump, in accordance with Boeing Alert Service Bulletin 767-28A0083 
(for Model 767-200, -300, and -300F airplanes) or 767-28A0084 (for 
Model 767-400ER airplanes), both Revision 1, dated April 26, 2007; 
as applicable.

Installation According to Previous Issue of Service Bulletin

    (g) Installing an automatic shutoff system is also acceptable 
for compliance with the requirements of paragraph (f) of this AD if 
done before the effective date of this AD in accordance with Boeing 
Alert Service Bulletin 767-28A0083 or 767-28A0084, both dated May 3, 
2006; as applicable.

Revision of Airplane Flight Manual (AFM)

    (h) Concurrently with accomplishing the actions required by 
paragraph (f) of this AD: Revise the Boeing 767 AFM as specified in 
paragraphs (h)(1) and (h)(2) of this AD. This may be done by 
inserting a copy of this AD into the AFM.
    (1) Revise Section 1, Certificate Limitations, to include the 
following:

    ``Intentional dry running of a center tank fuel pump (CTR L FUEL 
PUMP or CTR R FUEL PUMP message displayed on EICAS) is prohibited.
    Do not reset a tripped fuel pump or fuel pump control circuit 
breaker.''

    (2) Revise Section 3.1, Normal Procedures, to include the 
following:

``CENTER TANK FUEL PUMPS

    Center tank fuel pumps must not be ``ON'' unless personnel are 
available in the flight deck to monitor low PRESS lights.
    For ground operations prior to engine start:
    The center tank fuel pump switches must not be positioned ON 
unless the center tank contains usable fuel. With center tank fuel 
pump switches ON, verify both center tank fuel pump low PRESS lights 
are illuminated and EICAS CTR L FUEL PUMP and CTR R FUEL PUMP 
messages are displayed.
    For ground operations after engine start and flight operations: 
The center tank fuel pump switch must be selected OFF when the 
respective CTR L FUEL PUMP or CTR R FUEL PUMP message displays. Both 
center tank fuel pump switches must be selected OFF when either the 
CTR L FUEL PUMP or CTR R FUEL PUMP message displays if the center 
tank is empty. During cruise flight, both center tank pump switches 
may be reselected ON whenever center tank usable fuel is indicated.

DE-FUELING AND FUEL TRANSFER

    When transferring fuel or de-fueling center or main wing tanks, 
the center fuel pump low PRESS must be monitored and the fuel pump 
switches positioned to ``OFF'' at the first indication of low 
pressure. Prior to transferring fuel or de-fueling, conduct a lamp 
test of the respective fuel pump low PRESS lights.''

    Note 2: When statements identical to those in paragraph (g) of 
this AD have been included in the general revisions of the AFM, the 
general revisions may be inserted into the AFM, and the copy of this 
AD may be removed from the AFM.

Revision of Airworthiness Limitations

    (i) Concurrently with accomplishing the actions required by 
paragraph (f) of this AD: Revise Section 9 of the Boeing 767 
Maintenance Planning Data (MPD) Document D622T001-9, ``Airworthiness 
Limitations (AWLs) and Certification Maintenance Requirements 
(CMRs),'' to incorporate Revision March 2006. Accomplishing the 
revision in accordance with a later revision of the MPD is an 
acceptable method of compliance if the revision is approved by the 
Manager, Seattle Aircraft Certification Office (ACO), FAA.

Placard Installation

    (j) For Model 767-200, -300, or -300F airplanes that meet the 
conditions of paragraphs (j)(1) and (j)(2) of this AD: Within 30 
days after the effective date of this AD, install a placard in the 
flight deck adjacent to each pilot's primary flight display, to 
alert the flight crew to follow the procedures required by paragraph 
(b) of AD 2001-15-08. The placard must include the following 
statement:

    ``AD 2001-15-08 fuel usage restrictions required.''

Alternative placard wording may be used if approved by an 
appropriate FAA Principal Operations Inspector. Alternative placard 
methods and alternative methods of mixed fleet configuration control 
may be used if submitted for review in accordance with the 
procedures specified in paragraph (l) of this AD.
    (1) The airplane is operated in a fleet of airplanes on which 
the actions specified in paragraph (f) of this AD have been done on 
at least one of the fleet's airplanes.
    (2) The actions specified in paragraph (i) of AD 2001-15-08 
(installation of modified center tank override and override/jettison 
fuel pumps that are not subject to the unsafe condition described in 
this AD) or paragraph (f) of this AD have not been done on the 
airplane.

    Note 3: If the actions specified in paragraph (f) of this AD 
have been done on all airplanes operated within an operator's fleet, 
or if operation according to the fuel usage restrictions of AD 2001-
15-08 is maintained until automatic shutoff systems are installed on 
all airplanes in an operator's fleet: No placard is necessary before 
removal of the wet shutoff restrictions of AD 2001-15-08.


[[Page 51728]]



Terminating Action for AD 2001-15-08

    (k) For airplanes that have automatic shutoff systems installed: 
Accomplishment of paragraphs (f) and (j) of this AD terminates the 
requirements of paragraphs (b) and (c) of AD 2001-15-08.

Alternative Methods of Compliance (AMOCs)

    (l)(1) The Manager, Seattle Aircraft Certification Office (ACO), 
FAA, 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.

    Issued in Renton, Washington, on August 31, 2007.
Stephen P. Boyd,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E7-17830 Filed 9-10-07; 8:45 am]

BILLING CODE 4910-13-P
