
[Federal Register: October 19, 2009 (Volume 74, Number 200)]
[Proposed Rules]               
[Page 53436-53438]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr19oc09-21]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2009-0908; Directorate Identifier 2009-NM-067-AD]
RIN 2120-AA64

 
Airworthiness Directives; Boeing Model 757 Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for 
certain Boeing Model 757 airplanes. This proposed AD would require 
replacing the power control relays for the fuel boost pumps and 
override pumps with new relays having a ground fault interrupt (GFI) 
feature. This proposed AD results from fuel system reviews conducted by 
the manufacturer. We are proposing this AD to prevent damage to the 
fuel pumps caused by electrical arcing that could introduce an ignition 
source in the fuel tank, 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 December 3, 
2009.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://
www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this proposed AD, contact 
Boeing Commercial Airplanes, Attention: Data & Services Management, 
P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone 206-
544-5000, extension 1; fax 206-766-5680; e-mail me.boecom@boeing.com; 
Internet https://www.myboeingfleet.com. You may review copies of the 
referenced service information at the FAA, Transport Airplane 
Directorate, 1601 Lind Avenue SW., Renton, Washington. For information 
on the availability of this material at the FAA, call 425-227-1221 or 
425-227-1152.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (telephone 800-647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

FOR FURTHER INFORMATION CONTACT: Georgios Roussos, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue SW., Renton, Washington 98057-
3356; telephone (425) 917-6482; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2009-0908; 
Directorate Identifier 2009-NM-067-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://
www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    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 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

[[Page 53437]]

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.
    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.
    As part of the SFAR 88 required review, Boeing determined that the 
power control relays for the fuel boost pumps and override pumps should 
be replaced with new relays having a ground fault interrupt (GFI) 
feature. The relays are located in the P33 and P37 equipment panels in 
the main equipment center. The GFI feature is intended to protect the 
fuel pumps from damage caused by electrical arcing by removing 
electrical power from the pump if a ground fault is detected. 
Electrical arcing, if not prevented, could introduce an ignition source 
in the fuel tank, 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 Boeing Alert Service Bulletin 757-28A0078, dated 
July 16, 2008 (for Boeing Model 757-200, 757-200CB, and 757-200PF 
series airplanes); and Boeing Alert Service Bulletin 757-28A0079, dated 
July 16, 2008 (for Boeing Model 757-300 series airplanes). These 
service bulletins describe procedures for replacing the power control 
relays for the fuel boost pumps and override pumps with new relays 
having a ground fault interrupt (GFI) feature. The replacement also 
includes an operational test of the fuel boost pumps, override pumps, 
and new relays.

FAA's Determination and Requirements of This Proposed AD

    We are proposing this AD because we evaluated all relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design. 
This proposed AD would require accomplishing the actions specified in 
the service information described previously.
    Airworthiness Limitation (AWL) 28-AWL-21, of Section 9 of the 
Boeing 757 Maintenance Planning Document (MPD) Document, D622N001-9, 
Revision March 2008, which was required by AD 2008-10-11, is also 
related to this proposed AD by including a repetitive operational test 
of the GFI relays, and repair of any failed GFI relay to ensure 
continued functionality of the GFI circuit.

Costs of Compliance

    We estimate that this proposed AD would affect 696 airplanes of 
U.S. registry. The following table provides the estimated costs for 
U.S. operators to comply with this proposed AD.

                                                                 Table--Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                        Number of U.S.-
                      Action                           Work hours     Average labor        Parts           Cost per        registered       Fleet cost
                                                                      rate per hour                        product         airplanes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Replacement.......................................               7              $80          $12,600          $13,160              696       $9,159,360
--------------------------------------------------------------------------------------------------------------------------------------------------------

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 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 this 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.
    You can find our regulatory evaluation and the estimated costs of 
compliance in the AD Docket.

List of Subjects in 14 CFR Part 39

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

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

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

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


Sec.  39.13  [Amended]

    2. The FAA amends Sec.  39.13 by adding the following new AD:

    Boeing: Docket No. FAA-2009-0908; Directorate Identifier 2009-
NM-067-AD.

Comments Due Date

    (a) We must receive comments by December 3, 2009.

[[Page 53438]]

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 757-200, -200PF, -200CB, and 
-300 series airplanes, certificated in any category; as identified 
in the applicable service bulletin in paragraphs (c)(1) or (c)(2) of 
this AD.
    (1) For Model 757-200, -200PF, and -200CB series airplanes: 
Boeing Alert Service Bulletin 757-28A0078, dated July 16, 2008.
    (2) For Model 757-300 series airplanes: Boeing Alert Service 
Bulletin 757-28A0079, dated July 16, 2008.

Subject

    (d) Air Transport Association (ATA) of America Code 28: Fuel.

Unsafe Condition

    (e) This AD results from fuel system reviews conducted by the 
manufacturer. The Federal Aviation Administration is issuing this AD 
to prevent damage to the fuel pumps caused by electrical arcing that 
could introduce an ignition source in the fuel tank, which, in 
combination with flammable fuel vapors, could result in a fuel tank 
explosion and consequent loss of the airplane.

Compliance

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

Replacement

    (g) Within 60 months after the effective date of this AD: 
Replace the power control relays for the fuel boost pumps and 
override pumps with new relays having a ground fault interrupt (GFI) 
feature, and do an operational test, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin 757-
28A0078, dated July 16, 2008 (for Model 757-200, -200CB, and -200PF 
airplanes); or Boeing Alert Service Bulletin 757-28A0079, dated July 
16, 2008 (for Model 757-300 airplanes).

Alternative Methods of Compliance (AMOCs)

    (h)(1) The Manager, Seattle Aircraft Certification Office (ACO), 
FAA, has the authority to approve AMOCs for this AD, if requested 
using the procedures found in 14 CFR 39.19. Send information to 
ATTN: Georgios Roussos, Aerospace Engineer, Systems and Equipment 
Branch, ANM-130S, FAA, Seattle ACO, 1601 Lind Avenue, SW., Renton, 
Washington 98057-3356; telephone (425) 917-6482; fax (425) 917-6590. 
Or, e-mail information to 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.
    (2) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Before using any approved AMOC on any airplane to which the AMOC 
applies, notify your principal maintenance inspector (PMI) or 
principal avionics inspector (PAI), as appropriate, or lacking a 
principal inspector, your local Flight Standards District Office. 
The AMOC approval letter must specifically reference this AD.


    Issued in Renton, Washington, on September 30, 2009.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E9-24987 Filed 10-16-09; 8:45 am]

BILLING CODE 4910-13-P
