[Federal Register Volume 65, Number 10 (Friday, January 14, 2000)]
[Rules and Regulations]
[Pages 2285-2287]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-876]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 99-NM-342-AD; Amendment 39-11480; AD 99-26-21]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737-300, -400, -500, -600,
-700, and -800 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 737-300, -400, -500, -600, -700,
and -800 series airplanes. This action requires a one-time detailed
visual inspection of certain wire bundles and hydraulic hoses for the
electric motor driven pump (EMDP) for hydraulic system ``B'' located in
the right main wheel well to detect discrepancies; and corrective
actions, if necessary. This amendment is prompted by a report that the
wire bundle to the EMDP had been chafed by the pressure hose for
hydraulic system ``B'' on a Model 737-700 series airplane, and reports
of failed or damaged case drain or pressure hoses on the EMDP for
hydraulic system ``B'' on Model 737-400 series airplanes. The actions
specified in this AD are intended to prevent electrical arcing due to
chafing between certain hydraulic hoses and adjacent wire bundles,
which could result in a consequent increased risk of fire.
DATES: Effective January 31, 2000.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of January 31, 2000.
Comments for inclusion in the Rules Docket must be received on or
before March 14, 2000.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 99-NM-342-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: Stephen S. Oshiro, Aerospace Engineer,
Systems and Equipment Branch, ANM-130S, FAA, Transport Airplane
Directorate, Seattle Aircraft Certification Office, 1601 Lind Avenue,
SW., Renton, Washington 98055-4056; telephone (425) 227-2793; fax (425)
227-1181.
SUPPLEMENTARY INFORMATION: The FAA has received one report from an
operator of a Boeing Model 737-700 series airplane describing how one
of the three electrical wires in the wire bundle to the electric motor
driven pump (EMDP) had chafed the pressure hose for hydraulic system
``B.'' The FAA also has received several reports of failed or damaged
case drain or pressure hoses on the EMDP for hydraulic system ``B'' for
Boeing Model 737-300, -400, and -500 series airplanes. Chafing between
the hydraulic case drain and pressure hoses could damage the hoses, and
cause a hydraulic leak and failure of the pressure hose. Chafing
between the wire bundle and hydraulic hoses could damage those
components, and lead to electrical arcing between the components and a
consequent hydraulic leak, which could result in an increased risk of
fire.
Explanation of Relevant Service Information
The FAA has reviewed and approved Boeing Alert Service Bulletin
737-29A1076, Revision 1 (for Model 737-300, -400, and -500 series
airplanes), and Boeing Alert Service Bulletin 737-29A1077, Revision 1
(for Model 737-600, -700, and -800 series airplanes); both dated
October 21, 1999; which describe procedures for an inspection of wire
bundles W0334 and W5230, and the hydraulic case drain and pressure
hoses for the EMDP for hydraulic system ``B'' to detect any
discrepancies; and corrective actions, if necessary. Corrective actions
include repair of the wire bundles if any damage is found; replacement
of any hose that is damaged outside specified limits, and any
incorrectly sized or loose components; and certain modifications.
Modifications include adjusting or changing certain support clamps,
fittings, and check valves; and installing additional clamps and
spacers in the hydraulic hoses to obtain specified separation between
the wire bundle and the hoses. For certain EMDP's, modifications also
include ensuring that certain components are attached correctly.
The alert service bulletins also specify a test of the EMDP if wire
bundles W0334 or W5230 were repaired, or a leak test if the hydraulic
case drain or pressure hoses were replaced in accordance with either
Part 1 or Part 2 of the Accomplishment Instructions of the Boeing alert
service bulletins, as applicable.
Explanation of Requirements of the Rule
Since an unsafe condition has been identified that is likely to
exist or develop on other Boeing Model 737-300, -400, -500, -600, -700,
and -800 series airplanes of the same type design, this AD is being
issued to prevent electrical arcing due to chafing between certain
hydraulic hoses and adjacent wire bundles, which could result in a
consequent increased risk of fire. This AD requires a one-time detailed
visual inspection of wire bundles W0334 and W5230 and the hydraulic
case drain and pressure hoses for the EMDP for hydraulic system ``B''
located in the right main wheel well to detect discrepancies; and
corrective actions, if necessary. The actions are required to be
accomplished in accordance with the alert service bulletins described
previously, except as described below.
[[Page 2286]]
Differences Between This AD and the Alert Service Bulletins
Operators should note that the alert service bulletins recommend
accomplishment of the inspection and corrective actions as soon as
manpower and equipment are available. However, the FAA has determined
that the compliance time proposed by the manufacturer would not address
the identified unsafe condition in a timely manner. In developing an
appropriate compliance time for this AD, the FAA considered not only
the manufacturer's recommendation, but the degree of urgency associated
with addressing the subject unsafe condition, the average utilization
of the affected fleet, and the time necessary to perform the inspection
(less than two hours). In light of all these factors, the FAA finds a
90-day compliance time for accomplishing the required actions to be
warranted, in that it represents an appropriate interval of time
allowable for affected airplanes to continue to operate without
compromising safety.
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-342-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:
99-26-21 Boeing: Amendment 39-11480. Docket 99-NM-342-AD.
Applicability: Model 737-300, -400, and -500 series airplanes,
as listed in Boeing Alert Service Bulletin 737-29A1076, Revision 1,
dated October 21, 1999; and Model 737-600, -700, and -800 series
airplanes, as listed in Boeing Alert Service Bulletin 737-29A1077,
Revision 1, dated October 21, 1999; 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 (e) 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 electrical arcing due to chafing between certain
hydraulic hoses and adjacent wire bundles, which could result in a
consequent increased risk of fire; accomplish the following:
Actions for Model 737-300, -400, and -500 Series Airplanes
(a) For certain Model 737-300, -400, and -500 series airplanes
on which the actions specified by Boeing Alert Service Bulletin 737-
29A1076, dated April 2, 1998, have not been accomplished: Within 90
days after the effective date of this AD, perform a one-time
detailed visual inspection of wire bundle W0334 and the hydraulic
case drain and pressure hoses for the electric motor driven pump
(EMDP) for hydraulic system ``B'' to detect any discrepancy (e.g.,
damage or chafing of wire bundle W0334 and the hydraulic case drain
and pressure hoses, and incorrect separation between those
components), in accordance with Part 1 of the Accomplishment
Instructions of Boeing Alert Service Bulletin 737-29A1076, Revision
1, dated October 21, 1999.
(1) If no discrepancy is found, no further action is required by
this paragraph.
(2) If any discrepancy is found, prior to further flight,
perform corrective actions in accordance with Part 1 of the
Accomplishment Instructions of the alert service bulletin.
Note 2: For the purposes of this AD, a detailed visual
inspection is defined as: ``An intensive examination of a specific
structural area, system, installation, or assembly to detect damage,
failure, or irregularity. Available lighting is normally
supplemented with a direct source of good lighting at an
[[Page 2287]]
intensity deemed appropriate by the inspector. Inspection aids such
as mirrors, magnifying lenses, etc. may be used. Surface cleaning
and elaborate access procedures may be required.''
(b) For certain Model 737-300, -400, and -500 series airplanes
on which the actions specified by Boeing Alert Service Bulletin 737-
29A1076, dated April 2, 1998, have been accomplished: Within 90 days
after the effective date of this AD, perform a one-time detailed
visual inspection of wire bundle W0334 and the hydraulic case drain
and pressure hoses for the EMDP for hydraulic system ``B'' to detect
any discrepancy (e.g., damage or chafing of wire bundle W0334 and
the hydraulic case drain and pressure hoses; and incorrect
separation between those components), in accordance with Part 2 of
the Accomplishment Instructions of Boeing Alert Service Bulletin
737-29A1076, Revision 1, dated October 21, 1999.
(1) If no discrepancy is found, no further action is required by
this paragraph.
(2) If any discrepancy is found, prior to further flight,
perform corrective actions in accordance with Part 2 of the
Accomplishment Instructions of the alert service bulletin.
Actions for Model 737-600, -700, and -800 Series Airplanes
(c) For certain Model 737-600, -700, and -800 series airplanes
on which the actions specified by Boeing Alert Service Bulletin 737-
29A1077, dated March 4, 1999, have not been accomplished: Within 90
days after the effective date of this AD, perform a one-time
detailed visual inspection of wire bundle W5230 and the hydraulic
case drain and pressure hoses for the EMDP for hydraulic system
``B'' to detect any discrepancy (e.g., damage or chafing of the
W5230 wire bundle and the hydraulic case drain and pressure hoses;
and incorrect separation between those components) in accordance
with Part 1 of the Accomplishment Instructions of Boeing Alert
Service Bulletin 737-29A1077, Revision 1, dated October 21, 1999.
(1) If no discrepancy is found, no further action is required by
this paragraph.
(2) If any discrepancy is found, prior to further flight,
perform corrective actions in accordance with Part 1 of the
Accomplishment Instructions of the alert service bulletin.
(d) For certain Model 737-600, -700, and -800 series airplanes
on which the actions specified by Boeing Alert Service Bulletin 737-
29A1077, dated March 4, 1999, have been accomplished: Within 90 days
after the effective date of this AD, perform a one-time detailed
visual inspection of wire bundle W5230 and the case drain and
pressure hoses for the EMDP for hydraulic system ``B'' to detect any
discrepancy (e.g., damage or chafing of the W5230 wire bundles and
the hydraulic case drain and pressure hoses; and incorrect
separation between those components), in accordance with Part 2 of
Boeing Alert Service Bulletin 737-29A1077, Revision 1, dated October
21, 1999.
(1) If no discrepancy is found, no further action is required by
this paragraph.
(2) If any discrepancy is found, prior to further flight,
perform corrective actions in accordance with Part 2 of the
Accomplishment Instructions of the alert service bulletin.
Alternative Methods of Compliance
(e) 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 Manager, 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 3: 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
(f) Special flight permits may be issued in accordance with
sections 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
(g) The inspection and corrective actions shall be done in
accordance with Boeing Alert Service Bulletin 737-29A1076, Revision
1, dated October 21, 1999; or Boeing Alert Service Bulletin 737-
29A1077, Revision 1, dated October 21, 1999; as applicable. 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.
(h) This amendment becomes effective on January 31, 2000.
Issued in Renton, Washington, on January 7, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 00-876 Filed 1-13-00; 8:45 am]
BILLING CODE 4910-13-U
