AD 2003-26-07
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | MD-90-30 | Airworthiness Directives; McDonnell Douglas MD-90-30 Airplanes |
Unsafe Condition
Internal overheating and arcing of circuit breakers and airplane wiring due to long-term use and breakdown of internal components of the circuit breakers, which could result in smoke and fire in the flight compartment and main cabin.
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Required Actions
Perform a one-time general visual inspection of the circuit breakers to determine if discrepant circuit breakers are installed. If discrepant circuit breakers are found, replace them with new, approved circuit breakers before further flight. Alternatively, review airplane maintenance records to determine if discrepant circuit breakers were installed after delivery.
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Compliance Time
Within 18 months after the effective date of this AD.
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Affected Aircraft
McDonnell Douglas Model MD-90-30 airplanes, as listed in Boeing Alert Service Bulletin MD90-24A081, Revision 01, dated March 7, 2003; certificated in any category.
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Federal Register Abstract
This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model MD-90-30 airplanes, that requires a one-time general visual inspection of the circuit breakers to determine if discrepant circuit breakers are installed, and corrective action if necessary. This action is necessary to prevent internal overheating and arcing of circuit breakers and airplane wiring due to long-term use and breakdown of internal components of the circuit breakers, which could result in smoke and fire in the flight compartment and main cabin. This action is intended to address the identified unsafe condition.
Document Text
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[Federal Register Volume 68, Number 250 (Wednesday, December 31, 2003)]
[Rules and Regulations]
[Pages 75396-75397]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 03-31851]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2002-NM-103-AD; Amendment 39-13404; AD 2003-26-07]
RIN 2120-AA64
Airworthiness Directives; McDonnell Douglas MD-90-30 Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
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SUMMARY: This amendment adopts a new airworthiness directive (AD),
applicable to certain McDonnell Douglas Model MD-90-30 airplanes, that
requires a one-time general visual inspection of the circuit breakers
to determine if discrepant circuit breakers are installed, and
corrective action if necessary. This action is necessary to prevent
internal overheating and arcing of circuit breakers and airplane wiring
due to long-term use and breakdown of internal components of the
circuit breakers, which could result in smoke and fire in the flight
compartment and main cabin. This action is intended to address the
identified unsafe condition.
DATES: Effective February 4, 2004.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of February 4, 2004.
ADDRESSES: The service information referenced in this AD may be
obtained from Boeing Commercial Aircraft Group, Long Beach Division,
3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Data
and Service Management, Dept. C1-L5A (D800-0024). This information may
be examined at the Federal Aviation Administration (FAA), Transport
Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton,
Washington; or at the FAA, Los Angeles Aircraft Certification Office,
3960 Paramount Boulevard, Lakewood, California; or at the Office of the
Federal Register, 800 North Capitol Street, NW., suite 700, Washington,
DC.
FOR FURTHER INFORMATION CONTACT: George Mabuni, Aerospace Engineer,
Systems and Equipment Branch, ANM-130L, FAA, Los Angeles Aircraft
Certification Office, 3960 Paramount Boulevard, Lakewood, California
90712-4137; telephone (562) 627-5341; fax (562) 627-5210.
SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal
Aviation Regulations (14 CFR part 39) to include an airworthiness
directive (AD) that is applicable to certain McDonnell Douglas Model
MD-90-30 airplanes was published in the Federal Register on June 11,
2003 (68 FR 34849). That action proposed to require a one-time general
visual inspection of the circuit breakers to determine if discrepant
circuit breakers are installed, and corrective action if necessary.
Comments
Interested persons have been afforded an opportunity to participate
in the making of this amendment. Due consideration has been given to
the single comment received.
Request for Clarification of Applicability
The commenter, an operator, requests clarification of the
applicability listed in the proposed AD. The commenter states that it
has nine airplanes that are included in the applicability listed in the
proposed AD. Because no Wood Electric circuit breakers were installed
on its newly delivered airplanes or installed on any airplane during
maintenance, those airplanes fall into ``Group 1, Condition 1,'' as
listed in Boeing Alert Service Bulletin MD90-24A081, Revision 01, dated
March 7, 2003 (which was referenced as the appropriate source of
service information for accomplishment of the inspection in the
proposed AD). For those airplanes, the alert service bulletin states
that no action is required. However, the proposed AD would require
those airplanes to be inspected to determine if any Wood Electric
circuit breaker is installed even though the commenter knows the
circuit breakers are not installed.
The FAA agrees that clarification is necessary. Paragraph (a) of
the AD does require that all airplanes listed in the applicability
statement of the AD be inspected to verify installation of the
discrepant circuit breaker. However, the airplane manufacturer has
determined that no Model MD-90-30 airplanes were delivered with the
subject discrepant circuit breakers installed. Therefore, instead of
accomplishing the inspection provided in paragraph (a) of the AD, we
will allow operators to review the airplane maintenance records to
determine if any discrepant circuit breaker was installed on the
airplane after delivery--if the part number of the circuit breakers can
be positively determined from that review. We have revised paragraph
(a) of this final rule accordingly.
Conclusion
After careful review of the available data, including the comment
noted above, the FAA has determined that air safety and the public
interest require the adoption of the rule with the change previously
described. The FAA has determined that this change will neither
increase the economic burden on any operator nor increase the scope of
the AD.
Change to Labor Rate
We have reviewed the figures we have used over the past several
years to calculate AD costs to operators. To account for various
inflationary costs in the airline industry, we find it necessary to
increase the labor rate used in these calculations from $60 per work
hour to $65 per work hour. The cost impact information, below, reflects
this increase in the specified hourly labor rate.
Cost Impact
There are approximately 126 airplanes of the affected design in the
worldwide fleet. The FAA estimates that 21 airplanes of U.S. registry
will be affected by this AD, that it will take approximately 20 work
hours per airplane to accomplish the required
[[Page 75397]]
inspection of the circuit breakers (over 700 installed on each
airplane), and that the average labor rate is $65 per work hour. Based
on these figures, the cost impact of the AD on U.S. operators is
estimated to be $27,300, or $1,300 per airplane.
The cost impact figure discussed above is based on assumptions that
no operator has yet accomplished any of the requirements of this AD
action, and that no operator would accomplish those actions in the
future if this AD were not adopted. The cost impact figures discussed
in AD rulemaking actions represent only the time necessary to perform
the specific actions actually required by the AD. These figures
typically do not include incidental costs, such as the time required to
gain access and close up, planning time, or time necessitated by other
administrative actions.
Regulatory Impact
The regulations adopted herein will 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. Therefore, it
is determined that this final rule does not have federalism
implications under Executive Order 13132.
For the reasons discussed above, I certify that this action (1) is
not a ``significant regulatory action'' under Executive Order 12866;
(2) is not a ``significant rule'' under 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. A final evaluation has been prepared for this action
and it is contained in the Rules Docket. A copy of it 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
0
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
0
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]
0
2. Section 39.13 is amended by adding the following new airworthiness
directive:
2003-26-07 McDonnell Douglas: Amendment 39-13404. Docket 2002-NM-
103-AD.
Applicability: Model MD-90-30 airplanes, as listed in Boeing
Alert Service Bulletin MD90-24A081, Revision 01, dated March 7,
2003; certificated in any category.
Compliance: Required as indicated, unless accomplished
previously.
To prevent internal overheating and arcing of circuit breakers
and airplane wiring due to long-term use and breakdown of internal
components of the circuit breakers, which could result in smoke and
fire in the flight compartment and main cabin, accomplish the
following:
Inspection and Replacement
(a) Within 18 months after the effective date of this AD:
Perform a one-time general visual inspection of the circuit breakers
to determine if discrepant circuit breakers are installed (includes
circuit breakers manufactured by Wood Electric and Wood Electric
Division of Brumfield Potter Corporations, and incorrect circuit
breakers installed per Boeing Alert Service Bulletin MD90-24A081,
dated February 14, 2002), per Boeing Alert Service Bulletin MD90-
24A081, Revision 01, dated March 7, 2003. Instead of performing the
one-time inspection, a review of the airplane maintenance records is
acceptable if the part number of the discrepant circuit breakers can
be positively determined by that review.
Note 1: For the purposes of this AD, a general visual inspection
is defined as: ``A visual examination of an interior or exterior
area, installation, or assembly to detect obvious damage, failure,
or irregularity. This level of inspection is made from within
touching distance unless otherwise specified. A mirror may be
necessary to enhance visual access to all exposed surfaces in the
inspection area. This level of inspection is made under normally
available lighting conditions such as daylight, hangar lighting,
flashlight, or droplight and may require removal or opening of
access panels or doors. Stands, ladders, or platforms may be
required to gain proximity to the area being checked.''
(1) If no discrepant circuit breaker is found: No further action
is required by this paragraph.
(2) If any discrepant circuit breaker is found: Before further
flight, replace the circuit breaker with a new, approved circuit
breaker, per the service bulletin.
Part Installation
(b) As of the effective date of this AD, no person shall install
a circuit breaker manufactured by Wood Electric Corporation or Wood
Electric Division of Potter Brumfield Corporation on any airplane.
Alternative Methods of Compliance
(c) In accordance with 14 CFR 39.19, the Manager, Los Angeles
Aircraft Certification Office, FAA, is authorized to approve
alternative methods of compliance for this AD.
Incorporation by Reference
(d) Unless otherwise provided in this AD, the actions shall be
done in accordance with Boeing Alert Service Bulletin MD90-24A081,
Revision 01, dated March 7, 2003. 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 Aircraft Group, Long Beach Division, 3855 Lakewood
Boulevard, Long Beach, California 90846, Attention: Data and Service
Management, Dept. C1-L5A (D800-0024). Copies may be inspected at the
FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,
Washington; or at the FAA, Los Angeles Aircraft Certification
Office, 3960 Paramount Boulevard, Lakewood, California; or at the
Office of the Federal Register, 800 North Capitol Street, NW., suite
700, Washington, DC.
Effective Date
(e) This amendment becomes effective on February 4, 2004.
Issued in Renton, Washington, on December 19, 2003.
Ali Bahrami,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 03-31851 Filed 12-30-03; 8:45 am]
BILLING CODE 4910-13-P
Source: Official FAA Source ↗
Retrieved: Apr 6, 2026
Rights: U.S. Government Public Domain
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