[Federal Register Volume 64, Number 169 (Wednesday, September 1, 1999)]
[Rules and Regulations]
[Pages 47656-47658]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-22531]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 99-NM-187-AD; Amendment 39-11283; AD 99-18-17]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737-100, -200, -300, -400,
and -500 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 all Boeing Model 737-100, -200, -300, -400, and -500
series airplanes. This action requires repetitive replacements of the
airplane battery with a new or reconditioned battery, and for certain
airplanes, replacement of the battery charger with a new or serviceable
battery charger. This action also requires performing repetitive tests
to determine the condition of a certain diode of the Generator Control
Units (GCU); and corrective actions, if necessary. This amendment is
prompted by an incident during which all electrical power was lost due
to a combination of a weak or depleted battery and the failure of a
certain diode of the GCU. The actions specified in this AD are intended
to prevent failure of all electrically powered airplane systems, which
could result in the inability to continue safe flight and landing.
DATES: Effective September 16, 1999.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of September 16, 1999.
Comments for inclusion in the Rules Docket must be received on or
before November 1, 1999.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 99-NM-187-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 a report of an incident
during which all electrical power was lost due to a combination of a
weak or depleted battery and the failure of a certain diode of the GCU
on a Boeing Model 737-200 series airplane. The electrical configuration
of a Boeing Model 737-200 series airplane is similar in design to that
of Boeing Model 737-100, -300, -400, and -500 series airplanes.
Therefore, Boeing Model 737-100, -300, -400, and -500 series airplanes
maybe subject to the same unsafe condition revealed on the Model 737-
200 series airplane. The report revealed that, during an approach for
landing, all electrical power was lost while the flight crew attempted
a routine, in-flight start of the Auxiliary Power Unit (APU).
Following from that incident, an assessment of airplane battery
maintenance was conducted, which resulted in the determination that
some operators have extended the maintenance intervals beyond those
recommended by the manufacturer. Such extended maintenance intervals
increase the likelihood of allowing an airplane to operate with a weak
or depleted airplane battery. The risk of a weak or depleted battery is
greater on Model 737-100 and -200 series airplanes than the Model 737-
300, -400 and -500 series airplanes because some of these airplanes
utilize an older version of a battery charger. This older version of a
battery charger has charging characteristics (overcharges and dries out
the battery) that are not compatible with the extended airplane battery
maintenance intervals. Additionally, certain diodes of the GCU have
exhibited a susceptibility to short-circuit failure. The cause of these
failures is under investigation.
If an attempt is made to start the APU during flight with a weak or
depleted battery, and a short-circuit failure of a certain diode of the
GCU has occurred, all electrical power could be lost for all airplane
systems. Such failure could result in the inability to continue safe
flight and landing.
Explanation of Relevant Service Information
The FAA has reviewed and approved Boeing Telex Message M-7200-99-
01528, dated March 5, 1999, which describes procedures for performing
repetitive tests to determine the condition of a certain diode of the
GCU; and corrective actions, if necessary. The corrective actions
include replacement of any GCU with a new or serviceable GCU if a
failed diode is detected, and for certain conditions, replacement of
the airplane battery with a new or reconditioned airplane battery.
The FAA also has reviewed and approved Boeing 737 Airplane
Maintenance Manual (AMM) Chapters 20-10-111 and 24-31-11. These service
documents describe the following:
AMM 20-10-111: For Model 737-100 and -200 series
airplanes, this AMM describes procedures for removal and installation
of black box units. For these airplane models, the airplane battery
charger is considered to be a black box unit.
AMM 24-31-11: For all Model 737-100, -200, -300, -400, and
-500 series airplanes this AMM describes procedures for removal and
installation of the airplane battery with a new or reconditioned
airplane battery. Additionally, the AMM describes
[[Page 47657]]
procedures for cleaning and checking any installed airplane battery.
Explanation of the Requirements of the Rule
Since an unsafe condition has been identified that is likely to
exist or develop on other airplanes of the same type design, this AD is
being issued to prevent failure of all electrically powered airplane
systems, which could result in the inability to continue safe flight
and landing. This AD requires accomplishment of the actions specified
in the service documents described previously. This AD also requires
that operators report results of inspection findings to the FAA.
Interim Action
Since the cause of the failures of the GCU's is under
investigation, this is considered to be interim action until final
action is identified, at which time the FAA may consider further
rulemaking.
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-187-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:
99-18-17 Boeing: Amendment 39-11283. Docket 99-NM-187-AD.
Applicability: All Model 737-100, -200, -300, -400, and -500
series airplanes; 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 (f) 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 all electrically powered airplane systems,
which could result in the inability to continue safe flight and
landing, accomplish the following:
(a) For Model 737-100 and -200 series airplanes equipped with
battery charger Boeing part number (P/N) 10-60701-1: Within 90 days
after the effective date of this AD, accomplish the requirements of
paragraphs (a)(1) and (a)(2) of this AD.
(1) Replace the airplane battery charger with a new or
serviceable airplane battery charger, Boeing P/N 10-60701-3, in
accordance with Chapter 20-10-111 of the Boeing 737 Airplane
Maintenance Manual (AMM); and
(2) Replace the airplane battery with a new or reconditioned
airplane battery in accordance with Chapter 24-31-11 of the Boeing
737 AMM. Thereafter, replace the airplane battery with a new or
reconditioned airplane battery at intervals not to exceed 750 flight
hours.
(b) For Model 737-300, -400, and -500 series airplanes: Within
90 days after the effective date of this AD, replace the airplane
battery with a new or reconditioned airplane battery in accordance
with Chapter 24-31-11 of the Boeing 737 AMM. Thereafter, replace the
airplane battery with a new or reconditioned airplane battery at
intervals not to exceed 750 flight hours.
(c) For all airplanes: Within 90 days after the effective date
of this AD, perform a test to determine the condition of diode CR910
of the Generator Control Units (GCU) in accordance with Boeing Telex
Message M-7200-99-01528, dated March 5, 1999.
Note 2: Any tests performed prior to the effective date of this
AD, in accordance with Boeing Telex Message M-7200-99-01528, dated
February 19, 1999, or dated March 4, 1999, are not considered
acceptable for compliance with the applicable action specified by
this AD.
[[Page 47658]]
(1) If all diodes pass the test, repeat the diode test
thereafter, at intervals not to exceed 600 flight hours.
(2) If any diode fails the test: Prior to further flight,
replace the GCU with a new or serviceable GCU, and if necessary, the
airplane battery with new or reconditioned airplane battery, and
repeat the diode test for the replaced GCU in accordance with the
telex message until successful completion of the test is achieved.
Repeat the diode test thereafter, at intervals not to exceed 600
flight hours.
(d) As of the effective date of this AD, no person shall install
a battery charger having P/N 10-60701-1 on any Model 737 series
airplane.
(e) Within 10 days after accomplishing the initial diode test
required by paragraph (c) of this AD, submit a report of the test
results (negative findings) to the Manager, Seattle Aircraft
Certification Office (ACO), FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; fax (425) 227-
1181. Information collection requirements contained in this
regulation have been approved by the Office of Management and Budget
(OMB) under the provisions of the Paperwork Reduction Act of 1980
(44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number
2120-0056.
Alternative Methods of Compliance
(f) 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 ACO. 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
(g) 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
(h) Except as provided by paragraphs (a) and (b) of this AD, the
test shall be done in accordance with Boeing Telex Message M-7200-
99-01528, dated March 5, 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. 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.
(i) This amendment becomes effective on September 16, 1999.
Issued in Renton, Washington, on August 24, 1999.
Vi L. Lipski,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 99-22531 Filed 8-31-99; 8:45 am]
BILLING CODE 4910-13-P
