[Federal Register Volume 63, Number 219 (Friday, November 13, 1998)]
[Rules and Regulations]
[Pages 63402-63404]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-30531]


-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-304-AD; Amendment 39-10889; AD 98-24-02]
RIN 2120-AA64


Airworthiness Directives; McDonnell Douglas Model MD-11 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

-----------------------------------------------------------------------

SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to certain McDonnell Douglas Model MD-11 series 
airplanes. This action requires a one-time inspection to identify the 
part numbers of two dimmer controls for the overhead instrument panel 
light and circuit breaker lightplate located in the flight compartment. 
For airplanes on which a dimmer control having an incorrect part number 
is installed, this action also requires replacing the dimmer control 
with a new part; modifying and reinstalling the existing dimmer 
control; or reinstalling a dimmer control following modification of the 
part by the part manufacturer. This amendment is prompted by reports of 
smoke emitting from the overhead panels in the cockpit area. The 
actions specified in this AD are intended to prevent an electrical 
failure in the overhead dimmer control due to overheating of a printed 
circuit board capacitor in the dimmer control, which could result in 
rupture of the capacitor and smoke in the flight compartment.

DATES: Effective November 30, 1998.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of November 30, 1998.
    Comments for inclusion in the Rules Docket must be received on or 
before Janaury 12, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 98-NM-304-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056.
    The service information referenced in this AD may be obtained from 
The Boeing Company, Douglas Products Division, 3855 Lakewood Boulevard, 
Long Beach, California 90846, Attention: Technical Publications 
Business Administration, Dept. C1-L51 (2-60). This information may be 
examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, 
SW., Renton, Washington; or at the FAA, Transport Airplane Directorate, 
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: Brett Portwood, Technical Specialist, 
Systems Safety and Integration, Systems and Equipment Branch, ANM-130L, 
FAA, Transport Airplane Directorate, Los Angeles Aircraft Certification 
Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; 
telephone (562) 627-5350; fax (562) 627-5210.

SUPPLEMENTARY INFORMATION: As part of its practice of re-examining all 
aspects of the service experience of a particular aircraft whenever an 
accident occurs, the FAA has become aware of several incidents of 
dimmer switches overheating and emitting smoke. These incidents 
occurred on McDonnell Douglas Model MD-11 series airplanes.
    Investigation has revealed that, when a need for higher lighting in 
the cockpit occurs (such as during a thunderstorm) and increased 
voltage is required, a strong burning odor could occur due to 
overheating of a capacitor within the dimmer unit. The dimmer unit is 
located in the overhead switch panel to the rear of the firewall shut 
off handles. This component is well protected by a unit housing and 
additional cover that separates the unit from other components in the 
cockpit overhead compartment.
    There is no evidence from any of the in-service events that any 
overheated capacitor has led to further aircraft damage beyond the 
capacitor. These incidents are not considered to be related to a recent 
accident that occurred off the coast of Nova Scotia involving a 
McDonnell Douglas Model MD-11 series airplane. The cause of that 
accident is still under investigation.
    Overheating of a capacitor inside the dimmer controls of the 
overhead instrument panel light and circuit breaker lightplate in the 
cockpit could cause an electrical failure in the overhead dimmer 
control, and consequent rupture of the PCB capacitor and smoke in the 
flight compartment.

Explanation of Relevant Service Information

    The FAA has reviewed and approved McDonnell Douglas Service 
Bulletin
    MD11-33-045, dated June 14, 1995, which describes the following 
procedures:
     Replacing any dimmer control, part number (P/N) 263-1, of 
the overhead instrument panel light and circuit breaker lightplate in 
the flight compartment with a new dimmer control, P/N 263-2.
     Modifying any dimmer control, P/N 263-1, of the overhead 
instrument panel light and circuit breaker lightplate to improve 
reliability and to extend the service life of dimmer controls by 
replacing one capacitor (C2) of the PCB assembly with a new, higher 
voltage capacitor that is more thermal resistant, reidentifying the 
existing dimmer control, and installing a new unit nameplate; and 
reinstalling the modified part.
     Returning the incorrect dimmer control, P/N 263-1, to the 
manufacturer of the part for modification and reidentification, and 
reinstalling the modified part.

[[Page 63403]]

    Accomplishment of either the replacement or modification specified 
in the service bulletin is intended to adequately address the 
identified unsafe condition.

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 an electrical failure in the overhead dimmer 
control due to overheating of a PCB capacitor in the dimmer control, 
which could result in rupture of the capacitor and smoke in the flight 
compartment. This AD requires a one-time visual inspection to identify 
the part numbers of two dimmer controls for the overhead instrument 
panel light and circuit breaker lightplate located in the flight 
compartment. For airplanes on which a dimmer control having a certain 
part number installed, this action also requires replacing the dimmer 
control with a new part; or replacing the existing dimmer control with 
a modified dimmer control.
    The FAA has been notified by the manufacturer that a 30-day lead 
time for obtaining the required parts will be required, following the 
30 days specified for inspection of the dimmer controls. The FAA 
considers that the 30-day lead time will accommodate the time necessary 
for affected operators to order and obtain the necessary parts required 
for the replacement of the dimmer controls, without adversely affecting 
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 98-NM-304-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:

98-24-02 McDonnell Douglas: Amendment 39-10889. Docket 98-NM-304-AD.

    Applicability: Model MD-11 series airplanes, serial numbers 447 
through 597 inclusive; 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 an electrical failure in the dimmer control for the 
overhead instrument panel light and circuit breaker lightplate due 
to overheating of a printed circuit board (PCB) capacitor in the 
dimmer control, which could result in rupture of the capacitor and 
smoke in the flight compartment, accomplish the following:
    (a) Within 30 days after the effective date of this AD, perform 
a one-time visual inspection of the two dimmer controls for the 
overhead instrument panel light and circuit breaker lightplate 
located in the flight compartment to identify the part numbers of 
the dimmer controls.
    (1) If all dimmer controls are identified as part number (P/N) 
263-2, no further action is required by this AD.
    (2) If any dimmer control is identified as P/N 263-1, within 30 
days after accomplishing the inspection specified by paragraph (a) 
of this AD, accomplish the actions required by paragraph (a)(2)(i), 
(a)(2)(ii), or (a)(2)(iii) of this AD, in accordance with McDonnell 
Douglas Service Bulletin MD11-33-045, dated June 14, 1995.
    (i) Replace any dimmer control, P/N 263-1, with a new dimmer 
control, P/N 263-2. Or

[[Page 63404]]

    (ii) Modify any dimmer control, P/N 263-1, and reinstall the 
modified and reidentified dimmer control in the flight compartment. 
Or
    (iii) Remove any dimmer control, P/N 263-1; return it for 
modification and reidentification to Olin Aerospace Company, 11441 
Willows Road NE, Redmond, Washington, 98073-9745; and reinstall the 
modified and reidentified dimmer control in the flight compartment.
    (b) As of the effective date of this AD, no person shall install 
on any McDonnell Douglas Model MD-11 series airplane, a dimmer 
control, P/N 263-1, unless that dimmer control has been modified and 
reidentified to P/N 263-2 in accordance with McDonnell Douglas 
Service Bulletin MD11-33-045, dated June 14, 1995.
    (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 Manager, Los Angeles 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, Los Angeles ACO.

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

    (d) 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.
    (e) Except as provided by paragraph (a) of this AD, the actions 
shall be done in accordance with McDonnell Douglas Service Bulletin 
MD11-33-045, dated June 14, 1995. 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 
The Boeing Company, Douglas Products Division, 3855 Lakewood 
Boulevard, Long Beach, California 90846, Attention: Technical 
Publications Business Administration, Dept. C1-L51 (2-60). Copies 
may be inspected at the FAA, Transport Airplane Directorate, 1601 
Lind Avenue, SW., Renton, Washington; or at the FAA, Transport 
Airplane Directorate, 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.
    (f) This amendment becomes effective on Novemebr 30, 1998.

    Issued in Renton, Washington, on November 9, 1998.
Vi L. Lipski,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-30531 Filed 11-12-98; 8:45 am]
BILLING CODE 4910-13-U