[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 [www.gpo.gov]
[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]
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