[Federal Register: October 29, 2003 (Volume 68, Number 209)]
[Proposed Rules]               
[Page 61637-61639]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr29oc03-14]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-NM-32-AD]
RIN 2120-AA64

 
Airworthiness Directives; McDonnell Douglas Model DC-9-31 and DC-
9-32 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to certain McDonnell Douglas Model 
DC-9-31 and DC-9-32 airplanes. This proposal would require replacement 
of certain power relays, and subsequent repetitive cleaning, 
inspecting, repairing, and testing of certain replaced power relays. 
This action is necessary to prevent internal arcing of the left and 
right generator power relays, auxiliary power relays, and external 
power relays, and consequent smoke and/or fire in the cockpit and 
cabin. This action is intended to address the identified unsafe 
condition.

DATES: Comments must be received by December 15, 2003.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2003-NM-32-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9 a.m. and 3 p.m., Monday through Friday, except 
Federal holidays. Comments may be submitted via fax to (425) 227-1232. 
Comments may also be sent via the Internet using the following address: 9-anm-nprmcomment@faa.gov. Comments sent via fax or the Internet must 
contain ``Docket No. 2003-NM-32-AD'' in the subject line and need not 
be submitted in triplicate. Comments sent via the Internet as attached 
electronic files must be formatted in Microsoft Word 97 or 2000 or 
ASCII text.
    The service information referenced in the proposed rule 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 FAA, Transport Airplane Directorate, 1601 Lind 
Avenue, SW., Renton, Washington; or at the FAA, Los Angeles Aircraft 
Certification Office, 3960 Paramount Boulevard, Lakewood, California.

FOR FURTHER INFORMATION CONTACT: Elvin Wheeler, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130L, FAA, Los Angeles Aircraft 
Certification Office, 3960 Paramount Boulevard, Lakewood, California 
90712-4137; telephone (562) 627-5344; fax (562) 627-5210.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed 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 above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this action may be changed in 
light of the comments received.
    Submit comments using the following format:
    [sbull] Organize comments issue-by-issue. For example, discuss a 
request to change the compliance time and a request to change the 
service bulletin reference as two separate issues.
    [sbull] For each issue, state what specific change to the proposed 
AD is being requested.
    [sbull] Include justification (e.g., reasons or data) for each 
request.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed 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 summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this action must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2003-NM-32-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules 
Docket No. 2003-NM-32-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received reports indicating that the alternating 
current (AC) cross-tie relay shorted out internally on McDonnell 
Douglas Model DC-9 series airplanes, which caused severe smoke and burn 
damage to the relay, aircraft wiring, and adjacent panels. 
Investigation revealed that the electrical fire originated within the 
cross-tie relay of the power distribution system. The cause of this 
incident has been attributed to a phase-to-phase short within the 
relay. This condition, if not corrected, could result in in-flight 
electrical fires.

Other Relevant Rulemaking

    We have previously issued AD 2002-26-13, amendment 39-13001 (68 FR 
33, January 2, 2003), applicable to certain McDonnell Douglas airplane 
models, as follows:

                        McDonnell Douglas Models
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DC-9-11, DC-9-12, DC-9-13, DC-9-14, DC-9-15, and DC-9-15F airplanes.
DC-9-21 airplanes.

[[Page 61638]]


DC-9-31, DC-9-32, DC-9-32 (VC-9C), DC-9-32F, DC-9-32F (C-9A, C-9B), DC-9-
 33F, DC-9-34, and DC-9-34F airplanes.
DC-9-41 airplanes.
DC-9-51 airplanes.
DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD-87)
 airplanes.
MD-88 airplanes.
------------------------------------------------------------------------

That AD requires replacement of certain power relays, and subsequent 
repetitive cleaning, inspecting, repairing, and testing of certain 
replaced power relays. The actions specified by that AD are intended to 
prevent internal arcing of the left and right generator power relays, 
auxiliary power relays, and external power relays, and consequent smoke 
and/or fire in the cockpit and cabin.
    Since issuance of AD 2002-26-13, we have determined that the same 
unsafe condition addressed in that AD may exist on four additional 
Model DC-9 series airplanes. We were advised that Model DC-9-31 
airplanes having manufacturer's fuselage numbers 1039 and 1046, and 
Model DC-9-32 having manufacturer's fuselage numbers 0268 and 0505 were 
omitted inadvertently from the applicability of that AD because those 
airplanes had been excluded inadvertently from the effectivity of 
paragraph 1.A of Boeing Alert Service Bulletin DC9-24A191, Revision 01, 
dated January 9, 2002, as cited in AD 2002-26-13. Therefore, these 
additional airplanes are also subject to the same unsafe condition 
addressed in AD 2002-26-13.

Explanation of Relevant Service Information

    We have reviewed and approved Boeing Alert Service Bulletin DC9-
24A191, Revision 02, dated January 7, 2003. The service bulletin 
describes procedures for a one-time inspection of the generator power 
relays, auxiliary power relays, and external power relays to determine 
if a certain Sundstrand (Westinghouse) part number (P/N) is installed; 
and corrective actions, if necessary. The corrective actions include 
modifying and reidentifying the power relay assemblies; installing 
certain power relay assemblies within service interval limits; 
replacing the existing power relay assemblies with power relay 
assemblies that are within service interval limits; and cleaning, 
inspecting, repairing, and testing of relay assemblies; as applicable. 
The revised service bulletin adds four fuselage numbers to the 
effectivity. No more work is necessary on airplanes changed as shown in 
Revision 01 of this service bulletin. Accomplishment of the actions 
specified in the service bulletin is intended to adequately address the 
identified unsafe condition.
    The procedures specified by Revision 02 of the service bulletin are 
essentially the same as those procedures specified in the Revision 01 
Boeing Alert Service Bulletin DC9-24A191.
    Accomplishment of the actions specified in AD 2002-26-13 is 
acceptable for compliance with the requirements of this proposed AD.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other products of this same type design, the 
proposed AD would require accomplishment of the actions specified in 
the service bulletin described previously, except as discussed below.
    Since this proposed AD expands the applicability of AD 2002-26-13, 
we have considered a number of factors in determining whether to issue 
a new proposed AD or to supersede the ``old'' AD. We have considered 
the entire fleet size that would be affected by superseding AD 2002-26-
13 and the consequent workload associated with revising maintenance 
record entries. In light of this, we have determined that a less 
burdensome approach is to issue a separate AD applicable only to the 
four additional airplanes. This proposed AD would not supersede AD 
2002-26-13; airplanes listed in the applicability of AD 2002-26-13 are 
required to continue to comply with the requirements of that AD. This 
proposed AD is a separate AD action, and is applicable only to 
McDonnell Douglas Model DC-9-31 airplanes having manufacturer's 
fuselage numbers 1039 and 1046, and Model DC-9-32 airplanes having 
manufacturer's fuselage numbers 0268 and 0505; certificated in any 
category.

Differences Between Relevant Service Information and Proposed Rule

    Operators should note that, although the procedures described in 
Boeing Alert Service Bulletin DC9-24A191, Revision 02, dated January 7, 
2003, specify maintenance (i.e., clean, inspect, repair, and test) of 
power relays, Sundstrand (Westinghouse) P/N 9008D09 series, when they 
are beyond service interval limits, this proposed AD would not require 
those procedures. The design of the main contact arc box for this relay 
is entirely different than that of power relays, Sundstrand 
(Westinghouse) P/Ns 914F567-3 and -4, and is not susceptible to the 
same type of failure in the AC cross-tie position. Therefore, we have 
determined that power relays having Sundstrand (Westinghouse) P/N 
9008D09 series are not subject to the identified unsafe condition of 
this proposed AD.
    Operators should also note that the proposed AD would not require 
installation of certain power relays or replacement of the existing 
power relays with power relays that are ``within service interval 
limits'' (i.e., 7,000 flight hours) as described in the service 
bulletin. The FAA has determined that any generator power relay, 
auxiliary power relay, or external power relay having Sundstrand 
(Westinghouse) P/N 914F567-4 that is removed from the airplane must go 
through maintenance and be made serviceable before the power relay can 
be reinstalled on an airplane. Therefore, the proposed AD would require 
cleaning, inspecting, repairing, and testing of power relays having 
Sundstrand (Westinghouse) P/N 914F567-4, or replacing those power 
relays with serviceable power relays having Sundstrand (Westinghouse) 
P/N 9008D09 series or 914F567-4. The proposed AD also would require 
subsequent repetitive cleaning, inspecting, repairing, and testing of 
power relays having Sundstrand (Westinghouse) P/N 914F567-4.

Cost Impact

    There are approximately 4 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 2 airplanes of U.S. registry 
would be affected by this proposed AD, that it would take approximately 
2 work hours per airplane to accomplish the proposed inspection, and 
that the average labor rate is $65 per work hour. Based on these 
figures, the cost impact of the proposed AD on U.S. operators is 
estimated to be $260, or $130 per airplane.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of the proposed requirements of 
this AD action, and that no operator would accomplish those actions in 
the future if this proposed 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 proposed herein would not have a substantial direct

[[Page 61639]]

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 proposal would not have federalism implications 
under Executive Order 13132.
    For the reasons discussed above, I certify that this proposed 
regulation (1) Is not a ``significant regulatory action'' under 
Executive Order 12866; (2) is not a ``significant rule'' under the DOT 
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); 
and (3) if promulgated, 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 copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting the Rules 
Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
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:

McDonnell Douglas: Docket 2003-NM-32-AD.
    Applicability: Model DC-9-31 airplanes having manufacturer's 
fuselage numbers 1039 and 1046, and Model DC-9-32 airplanes having 
manufacturer's fuselage numbers 0268 and 0505; certificated in any 
category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent internal arcing of the left and right generator power 
relays, auxiliary power relays, and external power relays, and 
consequent smoke and/or fire in the cockpit and cabin, accomplish 
the following:

Inspection

    (a) Within 24 months after the effective date of this AD, 
perform a one-time inspection of the left and right generator power 
relays, auxiliary power relays, and external power relays, to 
determine if Sundstrand (Westinghouse) part number (P/N) 914F567-3 
or -4 is installed, per Boeing Alert Service Bulletin DC9-24A191, 
Revision 02, dated January 7, 2003.

Replacement or Modification/Reidentification of Any Generator Power 
Relay, Auxiliary Power Relay, or External Power Relay, P/N 914F567-3

    (b) If any generator power relay, auxiliary power relay, or 
external power relay, Sundstrand (Westinghouse) P/N 914F567-3, is 
found installed during the inspection required by paragraph (a) of 
this AD, within 24 months after the effective date of this AD, do 
either action specified in paragraph (b)(1) or (b)(2) of this AD per 
the Accomplishment Instructions of Boeing Alert Service Bulletin 
DC9-24A191, Revision 02, dated January 7, 2003.
    (1) Replace the power relay having Sundstrand (Westinghouse) P/N 
914F567-3 with either a serviceable power relay having Sundstrand 
(Westinghouse) P/N 9008D09 series or 914F567-4.
    (2) Modify the power relay, Sundstrand (Westinghouse) P/N 
914F567-3, to a -4 configuration.

Maintenance or Replacement of Any Generator Power Relay, Auxiliary 
Power Relay, or External Power Relay, P/N 914F567-4

    (c) If any generator power relay, auxiliary power relay, or 
external power relay, Sundstrand (Westinghouse) P/N 914F567-4, is 
found installed during the inspection required by paragraph (a) of 
this AD, clean, inspect, repair, and test the relay, or replace the 
power relay with a serviceable power relay having Sundstrand 
(Westinghouse) P/N 9008D09 series or 914F567-4; per Boeing Alert 
Service Bulletin DC9-24A191, Revision 02, dated January 7, 2003; at 
the time specified in paragraph (c)(1) of this AD, except as 
provided by paragraph (c)(2) of this AD.
    (1) Within 7,000 flight hours after installation of the 
generator power relay, auxiliary power relay, or external power 
relay, Sundstrand (Westinghouse) P/N 914F567-4, or within 24 months 
after the effective date of this AD, whichever occurs later.
    (2) For airplanes on which the flight hours since installation 
of any generator power relay, auxiliary power relay, or external 
power relay, Sundstrand (Westinghouse) P/N 914F567-4, cannot be 
determined: Within 24 months after the effective date of this AD.

Repetitive Maintenance of Generator Power Relay, Auxiliary Power Relay, 
or External Power Relay, Sundstrand (Westinghouse) P/N 914F567-4

    (d) Before or upon the accumulation of 7,000 flight hours on any 
generator power relay, auxiliary power relay, or external power 
relay, Sundstrand (Westinghouse) P/N 914F567-4 since accomplishing 
the action(s) required by either paragraph (b) or (c) of this AD, as 
applicable, clean, inspect, repair, and test; per Boeing Alert 
Service Bulletin DC9-24A191, Revision 02, dated January 7, 2003. 
Thereafter, repeat these actions at intervals not to exceed the 
accumulation of 7,000 flight hours on the power relay.

Credit for AD 2002-26-13, Amendment 39-13001

    (e) Accomplishment of the actions specified in AD 2002-26-13 is 
acceptable for compliance with the requirements of this AD.

Alternative Methods of Compliance

    (f) In accordance with 14 CFR 39.19, the Manager, Los Angeles 
Aircraft Certification Office (ACO), FAA, is authorized to approve 
alternative methods of compliance (AMOCs) for this AD.


    Issued in Renton, Washington, on October 23, 2003.
Ali Bahrami,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 03-27213 Filed 10-28-03; 8:45 am]

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