[Federal Register Volume 64, Number 139 (Wednesday, July 21, 1999)]
[Rules and Regulations]
[Pages 39005-39007]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-18365]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-113-AD; Amendment 39-11230; AD 99-15-10]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 777 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to certain Boeing Model 777 series airplanes. This action 
requires replacement of a certain engine-driven pump (EDP) supply 
shutoff valve, which is located in the aft strut fairing, with a new 
shutoff valve. This amendment is prompted by reports of failure of the 
shutoff valve due to corrosion in the direct current motor in the 
shutoff valve. The actions specified in this AD are intended to prevent 
failure of an EDP supply shutoff valve. Such failure, in the event of 
an engine fire, could result in an uncontrolled fire in the engine 
compartment.

DATES: Effective August 5, 1999.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of August 5, 1999.
    Comments for inclusion in the Rules Docket must be received on or 
before September 20, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 99-NM-113-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056.
    The service information referenced in this AD may be obtained from 
Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 
98124-2207. This information may be examined at the FAA, Transport 
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at 
the Office of the Federal Register, 800 North Capitol Street, NW., 
suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Kenneth W. Frey, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130S; FAA, Transport Airplane 
Directorate, Seattle Aircraft Certification Office (ACO), 1601 Lind 
Avenue, SW., Renton, Washington; telephone (425) 227-2673; fax (425) 
227-1181.

SUPPLEMENTARY INFORMATION: The FAA has received reports of failures of 
the engine-driven pump (EDP) supply shutoff valves located in the aft 
strut fairings. Subsequently, the airplane manufacturer investigated 
this failure mode and reported to the FAA that failure of the supply 
shutoff valves was caused by corrosion in the direct current (DC) 
motors in the valves. Such corrosion forms between the stator and rotor 
in the DC motor in the supply shutoff valve assembly. Since the DC 
motor drives the actuator in the motor-operated supply shutoff valve to 
the commanded position, corrosion in the motor prevents the motor and 
the actuator from operating. In the event of an engine fire, failure of 
an EDP supply shutoff valve, if not corrected, could result in an 
uncontrolled fire in the engine compartment.

[[Page 39006]]

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Alert Service Bulletin 
777-29A0022, Revision 1, dated May 21, 1999, which describes procedures 
for replacement of a certain EDP supply shutoff valve with a new EDP 
supply shutoff valve. The Boeing alert service bulletin references 
Parker-Hannifin Service Bulletin 2910044-29-48, ``Introduction of Motor 
Operated Shutoff Valve, Part Number (P/N) 2960034-101,'' as an 
additional source of service information to accomplish the replacement.

Explanation of the Requirements of the Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other Boeing Model 777 series airplanes of the same 
type design, this AD is being issued to prevent failure of an EDP 
supply shutoff valve due to corrosion in the DC motor in the shutoff 
valve. In the event of an engine fire, failure of an EDP supply shutoff 
valve could result in an uncontrolled fire in the engine compartment. 
This AD requires replacement of a certain EDP supply shutoff valve, 
which is located in the aft strut fairing, with a new shutoff valve.

Differences Between the AD and the Alert Service Bulletin

    Boeing Alert Service Bulletin 777-29A0022, Revision 1, specifies 
that the replacement actions required by this AD may be accomplished in 
accordance with the procedures specified in the alert service bulletin, 
or in accordance with an ``operator's equivalent procedure.'' However, 
this AD requires that the actions be accomplished in accordance with 
the procedures specified in the Boeing alert service bulletin. An 
``operator's equivalent procedure'' may be used only if approved as an 
alternative method of compliance in accordance with paragraph (c) of 
this AD.

Determination of Rule's Effective Date

    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this rule by 
submitting such written data, views, or arguments as they may desire. 
Communications shall identify the Rules Docket number and be submitted 
in triplicate to the address specified under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the rule. All comments submitted will be 
available, both before and after the closing date for comments, in the 
Rules Docket for examination by interested persons. A report that 
summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 99-NM-113-AD.'' The postcard will be date stamped and 
returned to the commenter.

Regulatory Impact

    The regulations adopted herein will not have substantial direct 
effects 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. Therefore, in 
accordance with Executive Order 12612, it is determined that this final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and that it is not a ``significant regulatory 
action'' under Executive Order 12866. It has been determined further 
that this action involves an emergency regulation under DOT Regulatory 
Policies and Procedures (44 FR 11034, February 26, 1979). If it is 
determined that this emergency regulation otherwise would be 
significant under DOT Regulatory Policies and Procedures, a final 
regulatory evaluation will be prepared and placed in the Rules Docket. 
A copy of it, if filed, may be obtained from the Rules Docket at the 
location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

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

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends part 39 of 
the Federal Aviation Regulations (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. Section 39.13 is amended by adding the following new 
airworthiness directive:

99-15-10 BOEING: Amendment 39-11230. Docket 99-NM-113-AD.

    Applicability: Model 777 series airplanes, equipped with an 
engine-driven pump supply shutoff valve having Boeing part number 
S271W741-21; certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must request approval for an 
alternative method of compliance in accordance with paragraph (c) of 
this AD. The request should include an assessment of the effect of 
the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent failure of an engine-driven pump (EDP) supply shutoff 
valve, which, in the event of an engine fire, could result in an 
uncontrolled fire in the engine compartment, accomplish the 
following:

Replacement

    (a) Except as provided by paragraph (b) of this AD, within 90 
days after the effective date of this AD, replace any EDP supply 
shutoff valve, Boeing part number (P/N) S271W741-21, that is located 
in each aft strut fairing, with a new EDP supply shutoff valve, 
Boeing P/N S271W741-22, in accordance with Boeing Alert Service 
Bulletin 777-29A0022, Revision 1, dated May 21, 1999.

[[Page 39007]]

    (b) Where Boeing Alert Service Bulletin 777-29A0022, Revision 1, 
dated May 21, 1999, specifies that replacements may be accomplished 
in accordance with an operator's ``equivalent procedure,'' those 
actions must be accomplished in accordance with the applicable 
chapter of the Boeing 777 Airplane Maintenance Manual (AMM) 
specified in the alert service bulletin.

Alternative Methods of Compliance

    (c) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Seattle Aircraft Certification Office (ACO), 
FAA, Transport Airplane Directorate. Operators shall submit their 
requests through an appropriate FAA Principal Maintenance Inspector, 
who may add comments and then send it to the Manager, Seattle ACO.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Seattle ACO.

Special Flight Permits

    (d) Special flight permits may be issued in accordance with 
Secs. 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 
21.197 and 21.199) to operate the airplane to a location where the 
requirements of this AD can be accomplished.

Incorporation by Reference

    (e) The replacement shall be done in accordance with Boeing 
Alert Service Bulletin 777-29A0022, Revision 1, dated May 21, 1999. 
This incorporation by reference was approved by the Director of the 
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 
51. Copies may be obtained from Boeing Commercial Airplane Group, 
P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be 
inspected at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue, SW., Renton, Washington; or at the Office of the Federal 
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.
    (f) This amendment becomes effective on August 5, 1999.

    Issued in Renton, Washington, on July 13, 1999.
D. L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-18365 Filed 7-20-99; 8:45 am]
BILLING CODE 4910-13-P