[Federal Register Volume 60, Number 179 (Friday, September 15, 1995)]
[Proposed Rules]
[Pages 47900-47903]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-22967]



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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 95-NM-131-AD]


Airworthiness Directives; McDonnell Douglas Models DC-9, DC-9-80, 
and MD-90-30 Series Airplanes, and Model MD-88 Airplanes, and C-9 
(Military) Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the supersedure of an exiting 
airworthiness directive (AD), applicable to certain McDonnell Douglas 
Model DC-9-80 series airplanes and Model MD-88 airplanes, that 
currently requires an inspection to detect chafing of or damage to the 
wire bundle in the overhead switch panel of the cockpit, application of 
spiral wrap to the wire bundle, and corrective actions, if necessary. 
That AD was prompted by reports of chafed and shorted wires that 
resulted in smoke emanating from the overhead switch panel of the 
cockpit. This action would expand the applicability of the rule to 
include certain Model DC-9, C-9 (military), and MD-90-30 series 
airplanes. This action also proposes to add a requirement to reroute 
the wire bundle to preclude chafing and damage. The actions specified 
by the proposed AD are intended to prevent the potential for fire and 
uncontrolled smoke throughout the cockpit as a result of chafing and 
shorting in the electrical wire bundles.

DATES: Comments must be received by November 13, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 95-NM-131-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except 
Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from McDonnell Douglas Corporation, 3855 Lakewood Boulevard, 
Long Beach, California 90846, Attention: Technical Publications 
Business Administration, Department 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 90712.

FOR FURTHER INFORMATION CONTACT: J. Kirk Baker, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130L, FAA, Los Angeles Aircraft 
Certification Office, 3960 Paramount Boulevard, Lakewood, California 
90712; telephone (310) 627-5345; fax (310) 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 notice may be changed in 
light of the comments received.
    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 notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 95-NM-131-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-103, Attention: Rules 
Docket No. 95-NM-131-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On April 25, 1995, the FAA issued AD 95-09-10, amendment 39-9213 
(60 FR 21977, May 4, 1995), applicable to certain McDonnell Douglas 
Model DC-9-80 series airplanes and Model MD-88 airplanes. That AD 
requires a one-time visual inspection to detect chafing of or damage to 
the wire bundle in the overhead switch panel of the cockpit, 
application of spiral wrap to the wire bundle, repair of chafed wire 
insulation, and splicing of damaged wires. That action was prompted by 
reports of chafed and shorted wires that resulted in smoke emanating 
from the overhead switch panel of the cockpit. The requirements of that 
AD are intended to prevent the potential for fire and uncontrolled 
smoke throughout the cockpit as a result of chafing and shorting in the 
electrical wire bundles.
    In the preamble to AD 95-09-10, the FAA indicated that the required 
actions were considered to be interim action, and that additional 
rulemaking action was being considered to require modification 
(rerouting) of the wire bundles. The FAA also indicated that subsequent 
rulemaking action may be proposed to require the same actions that are 
required by AD 95-09-10 be applicable to certain Model DC-9, C-9 
(military), and MD-90-30 series airplanes.
    The FAA now has determined that certain Model DC-9, C-9 (military), 
and MD-90-30 series airplanes are subject to the same unsafe condition 
as Model DC-9-80 series airplanes and Model MD-88 airplanes that were 
identified in the applicability of AD-95-09-10, The wire bundle in the 
overhead switch panel of the cockpit is routed similarly in all of 
these airplanes and, therefore, the same potential for wire chafing and 
damage exists on all of these airplanes. Further, the FAA has 
determined the rerouting the wire bundles in the overhead switch panel 
of the cockpit on these airplanes will preclude the potential for fire 
and uncontrolled smoke throughout the cockpit .
    Based on these determinations, the FAA finds that additional 
rulemaking is indeed necessary, and this proposed rule follows from 
these determinations.
    Additionally, the FAA has reviewed and approved McDonnell Douglass 
MD-90 Alert Service Bullletin MD90-24A001, dated April 11, 1995, which 
describes procedures for a one-time visual inspection to detect chafing 
of the wire bundle in the overhead switch panel of the cockpit, 
application of spiral wrap, repair of chafed wire insulation, and 
splicing of damaged wires. This service bulletin pertains only to 
certain Model MD-90 series airplanes.
    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 supersede AD 95-09-10 to continue to require a one-
time visual inspection to detect chafing of or damage to the wire 
bundle in the overhead switch panel of the cockpit, application of 
spiral wrap to the wire bundle, repair of chafed wire insulation, and 
splicing of damaged wires. For certain Model MD-90-30 series airplanes, 
the actions would be 

[[Page 47902]]
required to be accomplished in accordance with the alert service 
bulletin described previously. For certain Model DC-9, C-9 (military), 
DC-9-80 series airplanes, and Model MD-88 airplanes, the actions would 
continue to be required to be accomplished in accordance with McDonnell 
Douglas DC-9 Alert Service Bulletin DC9-24A157, dated April 11, 1995 
(which was referenced in AD 95-09-10 as the appropriate source of 
service information).
    Additionally, the proposed AD would add a requirement to reroute 
the wire bundle in accordance with a method approved by the FAA.
    As a result of recent communications with the Air Transport 
Association (ATA) of America, the FAA has learned that, in general, 
some operators may misunderstand the legal effect of AD's on airplanes 
that are identified in the applicability provision of the AD, but that 
have been altered or repaired in the area addressed by the AD. The FAA 
points out that all airplanes identified in the applicability provision 
of an AD are legally subject to the AD. If an airplane has been altered 
or repaired in the affected area in such a way as to affect compliance 
with the AD, the owner or operator is required to obtain FAA approval 
for an alternative method of compliance with the AD, in accordance with 
the paragraph of each AD that provides for such approvals. A note has 
been included in this notice to clarify this long-standing requirement.
    There are approximately 2,012 Model DC-9, C-9 (military, DC-9-80, 
and MD-90-30 series airplanes, and Model MD-88 airplanes of the 
affected design in the worldwide fleet. The FAA estimates that 816 
airplanes of U.S. registry would be affected by this proposed AD. The 
proposed requirement to inspect and spiral wrap the wire bundle would 
take approximately 3 work hours per airplane to accomplish, and the 
average labor rate is $60 per work hour. Required parts would cost 
approximately $5 per airplane. Based on these figures that total cost 
impact of these proposed actions on U.S. operators is estimated to be 
$185 per airplane.
    The requirement to inspect and spiral wrap the wire bundle, 
specified in this proposed rule, was previously required by AD 95-09-
10, which was applicable to 614 Model DC-9-80 series airplanes and 
Model MD-88 airplanes of U.S. registry. Based on the figures discussed 
above, the total cost impact of the current requirements of that AD on 
U.S. operators of Model DC-9-80 series airplanes and Model MD-88 
airplanes is estimated to be $113,590. In consideration of the 
compliance time and effective date of AD 95-09-10, the FAA assumes that 
U.S. operators of airplanes that are subject to the requirements of 
that AD have already initiated the required actions. Therefore, the 
proposed action to inspect and spiral wrap the wire bundle would add no 
new costs associated with those airplanes.
    However, this proposed action would also be applicable to 
approximately 202 Model DC-9, C-9 (military), and Model MD-9-30 series 
airplanes of U.S. registry. Based on the figures discussed above, the 
total new costs imposed by this proposal on U.S. operators of these 
airplanes are estimated to be $37,370. This figure is based on 
assumptions that no operator of these additional airplanes 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 
AD were not adopted.
    The newly proposed requirements of this AD action to reroute the 
wire bundle would be applicable to 816 Model DC-9, C-9 (military), DC-
9-80, and Model MD-90-30 series airplanes, and Model MD-88 airplanes of 
U.S. registry. The proposed requirement to reroute the wire bundle 
would take approximately 0.5 work hour per airplane to accomplish, and 
the average labor rate is $60 per work hour. Required parts would cost 
approximately $5 per airplane. Based on these figures the total cost 
impact of this proposed action on U.S. operators is estimated to be 
$28,560, or $35 per airplane.
    The regulations proposed herein would 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 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    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), 40101, 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing amendment 39-9213 (60 FR 
21977, May 4, 1995), and by adding a new airworthiness directive (AD), 
to read as follows:

McDonnell Douglas: Docket 95-NM-131-AD. Supersedes AD 95-09-10, 
Amendment 39-9213.

    Applicability: Models DC-9, C-9 (military), and DC-9-80 series 
airplanes, and Model MD-88 airplanes, as listed in McDonnell Douglas 
DC-9 Alert Service Bulletin DC9-24A157, dated April 11, 1995; and 
Model MD-90-30 series airplanes, as listed in McDonnell Douglas 
Alert Service Bulletin MD90-24A001, dated April 11, 1995; 
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 use the authority 
provided in paragraph (b) of this AD to request approval from the 
FAA. This approval may address either no action, if the current 
configuration eliminates the unsafe condition; or different actions 
necessary to address the unsafe condition described in this AD. Such 
a request should include an assessment of the effect of the changed 
configuration on the unsafe condition addressed by this AD. In no 
case does the presence of any modification, alteration, or repair 
remove any airplane from the applicability of this AD.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent the potential for fire and uncontrolled smoke 
throughout the cockpit, accomplish the follows:
    (a) For Model DC-9-80 series airplanes and Model MD-88 
airplanes: Within 90 days after May 19, 1995 (the effective date of 
AD 95-09-10, amendment 39-9213), perform a 

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visual inspection to detect chafing of or damage to the wire bundle in 
the overhead switch panel of the cockpit, in accordance with 
McDonnell Douglas Alert Service Bulletin DC9-24A157, dated April 11, 
1995.
    (1) If no chafing or damage is detected, prior to further 
flight, apply spiral wrap to the wire bundle in accordance with the 
alert service bulletin.
    (2) If the wire insulation is chafed, prior to further flight, 
repair it and then apply spiral wrap to the wire bundle, in 
accordance with the alert service bulletin.
    (3) If the wire conductor is damaged, prior to further flight, 
splice the wires and then apply spiral wrap to the wire bundle, in 
accordance with the alert service bulletin.
    (b) For Model DC-9 and C-9 (military), and MD-90-30 series 
airplanes: Within 6 months after the effective date of this AD, 
perform a visual inspection to detect chafing of or damage to the 
wire bundle in the overhead switch panel of the cockpit, in 
accordance with McDonnell Douglas CD-9 Alert Service Bulletin DC9-
24A157, dated April 11, 1995 [for Model DC-9 and C-9 (military) 
series airplanes], or McDonnell Douglas MD-90 Alert Service Bulletin 
MD90-24A001, dated April 11, 1995 (for Model MD-90-30 series 
airplanes), as applicable.
    (1) If no chafing or damage is detected, prior to further 
flight, apply spiral wrap to the wire bundle in accordance with the 
applicable alert service bulletin.
    (2) If the wire insulation is chafed, prior to further flight, 
repair it and then apply spiral wrap to the wire bundle, in 
accordance with the alert service bulletin.
    (3) If the wire conductor is damaged, prior to further flight, 
splice the wires and them apply spiral wrap to the wire bundle, in 
accordance with the applicable alert service bulletin.
    (c) Within 6 months after the effective date of this AD, reroute 
the wire bundle in the overhead switch panel of the cockpit in 
accordance with a method approved by the Manager, Los Angeles 
Aircraft Certification Office (ACO), FAA, Transport Airplane 
Directorate.
    (d) 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 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.
    Note 3: Alternative methods of compliance previously granted for 
amendment 39-9213, AD 95-09-10, continue to be considered as 
acceptable alternative methods of compliance with this amendment.

    (e) 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.

    Issued in Renton, Washington, on September 11, 1995.
D.L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 95-22967 Filed 9-14-95; 8:45 am]
BILLING CODE 4910-13-M