[Federal Register Volume 70, Number 30 (Tuesday, February 15, 2005)]
[Proposed Rules]
[Pages 7695-7697]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-2835]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-20355; Directorate Identifier 2004-NM-198-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 727 Airplanes, Equipped 
With An Auxiliary Fuel Tank Having a Fuel Pump Installed

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

[[Page 7696]]


ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for Boeing Model 727 airplanes equipped with an auxiliary fuel tank 
having a fuel pump installed. This proposed AD would require revising 
the airplane flight manual to include limitations on operating the fuel 
pumps for the auxiliary fuel tank. This proposed AD is prompted by a 
design review of the fuel pump installation, which revealed a potential 
unsafe condition related to the auxiliary fuel tank(s). We are 
proposing this AD to prevent dry operation of the fuel pumps for the 
auxiliary fuel tank, which could create a potential ignition source 
inside the auxiliary fuel tank that could result in a fire or explosion 
of the auxiliary fuel tank.

DATES: We must receive comments on this proposed AD by April 1, 2005.

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: Docket Management Facility, U.S. Department of 
Transportation, 400 Seventh Street SW, Nassif Building, room PL-401, 
Washington, DC 20590.
     By fax: (202) 493-2251.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street SW., Washington, DC, 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, P.O. Box 3707, Seattle, Washington 98124-
2207.
    You can examine the contents of this AD docket on the Internet at 
http://dms.dot.gov, or in person at the Docket Management Facility, 
U.S. Department of Transportation, 400 Seventh Street SW., room PL-401, 
on the plaza level of the Nassif Building, Washington, DC. This docket 
number is FAA-2005-20355; the directorate identifier for this docket is 
2004-NM-198-AD.

FOR FURTHER INFORMATION CONTACT: Sulmo Mariano, Aerospace Engineer, 
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification 
Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone 
(425) 917-6501; 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 under ADDRESSES. Include ``Docket No. FAA-2005-20355; 
Directorate Identifier 2004-NM-198-AD'' in the subject line 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 submitted 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 can review DOT's complete Privacy Act Statement in the 
Federal Register published on April 11, 2000 (65 FR 19477-78), or you 
can visit http://dms.dot.gov.

Examining the Docket

    You can examine the AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The Docket Management Facility office (telephone (800) 647-
5227) is located on the plaza level of the Nassif Building at the DOT 
street address stated in the ADDRESSES section. Comments will be 
available in the AD docket shortly after the DMS receives them.

Discussion

    The FAA has examined the underlying safety issues involved in 
recent 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 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.
    A design review of the fuel pump installation on the auxiliary fuel 
tank of Boeing Model 727 airplanes has revealed a potential unsafe 
condition related to the auxiliary fuel tank(s). Dry operation of the 
fuel pumps for the auxiliary fuel tank could cause metal-to-metal 
contact that may create high temperatures or sparks. This could create 
a potential ignition source inside the auxiliary fuel tank, which could 
result in a fire or explosion of the auxiliary fuel tank.

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

[[Page 7697]]

type design. Therefore, we are proposing this AD, which would require 
revising the airplane flight manual (AFM) to include limitations on 
operating the fuel pumps for the auxiliary fuel tank.
    In developing an appropriate compliance time for this AD, we 
considered the manufacturer's recommendation, the degree of urgency 
associated with the subject unsafe condition, and the average 
utilization of the affected fleet. In light of all of these factors, we 
find that a 30-day compliance time represents an appropriate interval 
of time for affected airplanes to continue to operate without 
compromising safety.

Costs of Compliance

    There are about 300 airplanes of the affected design in the 
worldwide fleet. This proposed AD would affect about 200 airplanes of 
U.S. registry. The proposed AFM revision would take about 1 work hour 
per airplane, at an average labor rate of $65 per work hour. Based on 
these figures, the estimated cost of the proposed AD for U.S. operators 
is $13,000, or $65 per airplane.

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. 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 FAA amends Sec.  39.13 by adding the following new 
airworthiness directive (AD):

Boeing: Docket No. FAA-2005-20355; Directorate Identifier 2004-NM-
198-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this AD action by April 1, 2005.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 727, 727C, 727-100, 727-
100C, 727-200, and 727-200F series airplanes; certificated in any 
category; equipped with an auxiliary fuel tank having a fuel pump 
installed.

Unsafe Condition

    (d) This AD was prompted by a design review of the fuel pump 
installation, which revealed a potential unsafe condition related to 
the auxiliary fuel tank(s). We are issuing this AD to prevent dry 
operation of the fuel pumps for the auxiliary fuel tank, which could 
create a potential ignition source inside the auxiliary fuel tank 
that could result in a fire or explosion of the auxiliary fuel tank.

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.

Airplane Flight Manual (AFM) Revision

    (f) Within 30 days after the effective date of this AD, revise 
the Limitations section of the AFM to contain the following 
information. This may be done by inserting a copy of this AD in the 
AFM.

Auxiliary Tank Fuel Pumps

    Auxiliary tank fuel pump switches must not be positioned `ON' 
unless the auxiliary tank(s) contain fuel. Auxiliary tank(s) fuel 
pumps must not be `ON' unless personnel are available in the flight 
deck to monitor low pressure lights.
    When established in a level attitude at cruise, if the auxiliary 
tank(s) contain usable fuel and the auxiliary tank(s) switches are 
`OFF,' the auxiliary tank(s) pump switches should be positioned `ON' 
again.
    Each auxiliary tank fuel pump switch must be positioned `OFF' 
without delay when the respective auxiliary tank fuel pump low 
pressure light illuminates.''

    Note 1: When text identical to that in paragraph (f) of this AD 
has 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.

Alternative Methods of Compliance (AMOCs)

    (g) The Manager, Seattle Aircraft Certification Office, FAA, has 
the authority to approve AMOCs for this AD, if requested in 
accordance with the procedures found in 14 CFR 39.19.

    Issued in Renton, Washington, on February 6, 2005.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 05-2835 Filed 2-14-05; 8:45 am]
BILLING CODE 4910-13-P