[Federal Register Volume 60, Number 73 (Monday, April 17, 1995)]
[Rules and Regulations]
[Pages 19158-19160]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-8826]



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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 95-NM-44-AD; Amendment 39-9198; AD 95-08-09]


Airworthiness Directives; McDonnell Douglas Model MD-11 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to certain McDonnell Douglas Model MD-11 series 
airplanes. This action requires modification of the support structure 
of the cargo liner. This amendment is prompted by a report of chafing 
and arcing in the vacuum waste exhaust heater that caused a spark to 
ignite the surrounding insulation blankets. The actions specified in 
this AD are intended to prevent fire and/or smoke due to chafing and 
arcing of the vacuum waste exhaust port heater.

DATES: Effective May 2, 1995.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of May 2, 1995.
    Comments for inclusion in the Rules Docket must be received on or 
before June 16, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 95-NM-44-AD, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056.
    The service information referenced in this AD may be obtained from 
McDonnell Douglas Corporation, P.O. Box 1771, Long Beach, California 
90801-1771, Attention: Business Unit Manager, Technical Administrative 
Support, Dept. L51, M.C. 2-98. This [[Page 19159]] information may be 
examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, 
SW., Renton, Washington; or at 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: Brett Portwood, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130L, FAA, Transport Airplane 
Directorate, 3960 Paramount Boulevard, Lakewood, California 90712-4137; 
telephone (310) 627-5347; fax (310) 627-5210.

SUPPLEMENTARY INFORMATION: Recently, an operator of McDonnell Douglas 
Model MD-11 series airplanes reported that chafing and arcing in the 
vacuum waste exhaust heater caused a spark to ignite the surrounding 
insulation blankets. Investigation revealed that the cutout in the 
baffle for the vacuum waste exhaust duct rubbed against the heater 
tape, which caused the heater tape to chafe. (Split heater cuffs were 
installed on the vacuum waste exhaust ducts of these airplanes in 
accordance with McDonnell Douglas Service Bulletin 38-15, dated October 
23, 1992.) This condition, if not corrected, could result in undetected 
fire and/or smoke due to chafing and arcing of the vacuum waste exhaust 
port heater.
    The FAA has reviewed and approved McDonnell Douglas Alert Service 
Bulletin MD11-38A044, dated March 22, 1995, which describes procedures 
for modification of the support structure of the cargo liner. This 
modification entails removing the baffle assemblies and trimming the 
insulation blankets surrounding the vacuum waste exhaust duct, which 
will reduce chafing and minimize the possibility of igniting the 
insulation blanket.
    The alert service bulletin includes two groups of airplanes in its 
effectivity listing: Airplanes identified as ``Group 1'' are equipped 
with split heater cuffs that were installed, after delivery, on the 
vacuum waste exhaust ducts of the heaters of these airplanes in 
accordance with McDonnell Douglas Service Bulletin 38-15, dated October 
23, 1992. Airplanes identified as ``Group 2'' are those on which the 
manufacturer accomplished a similar modification prior to delivery.
    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 fire and/or smoke due to chafing and arcing of 
the heater. This AD requires modification of the support structure of 
the cargo liner of airplanes identified in the alert service bulletin 
as Group 1 airplanes. The actions are required to be accomplished in 
accordance with the alert service bulletin described previously.
    Although all of the airplanes identified in the effectivity listing 
of the referenced alert service bulletin have had split heater cuffs 
installed on the vacuum waste exhaust ducts, those identified as Group 
1 airplanes differ significantly from those identified as Group 2 
airplanes: Group 1 airplanes have had split heater cuffs installed on 
the vacuum waste exhaust ducts, in accordance with McDonnell Douglas 
Service Bulletin 38-15, dated October 23, 1992; that service bulletin 
did not adequately specify the minimum distance between the baffle 
assemblies and the vacuum waste exhaust duct. Group 2 airplanes have 
had split heater cuffs installed during production using production 
drawings that adequately specified the minimum distance between the 
baffle assemblies and the vacuum waste exhaust duct. Consequently, 
because of the configuration of this installation, the FAA finds that 
the potential for chafing and arcing to occur on Group 1 airplanes is 
much greater. Further, a review of service history indicates that no 
incidents of chafing and arcing have occurred on Group 2 airplanes.
    In light of this, the FAA has determined that airplanes identified 
in the alert service bulletin as Group 2 airplanes are not subject to 
the unsafe condition. Accordingly, Group 2 airplanes have been excluded 
from the requirements of this AD.
    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 rule to clarify this long-standing requirement.
    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 95-NM-44-AD.'' The postcard will be date stamped and 
returned to the commenter.
    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 
[[Page 19160]] 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. App. 1354(a), 1421 and 1423; 49 U.S.C. 
106(g); and 14 CFR 11.89.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

95-08-09 McDonnell Douglas: Amendment 39-9198. Docket 95-NM-44-AD.

    Applicability: Model MD-11 series airplanes, as listed in 
McDonnell Douglas Alert Service Bulletin MD11-38A044, dated March 
22, 1995, and identified as ``Group 1 airplanes,'' on which split 
heater cuffs have been installed on the waste exhaust ducts of 
heaters in accordance with McDonnell Douglas MD-11 Service Bulletin 
38-15, dated October 23, 1992; 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 (c) 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 a fire and/or smoke due to chafing and arcing of the 
heater, accomplish the following:
    (a) Within 30 days after the effective date of this AD, modify 
the support structure of the cargo liner, in accordance with 
McDonnell Douglas MD-11 Alert Service Bulletin MD11-38A044, dated 
March 22, 1995.
    (b) As of the effective date of this AD, the support structure 
of the cargo liner on any airplane must be modified in accordance 
with McDonnell Douglas Alert Service Bulletin MD11-38A044, dated 
March 22 1995, prior to installing a vacuum waste exhaust port 
heater, P/N 62-5745, in accordance with McDonnell Douglas MD-11 
Service Bulletin 38-15, dated October 23, 1992.
    (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 
Secs. 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) The modification shall be done in accordance with McDonnell 
Douglas Alert Service Bulletin MD11-38A044, dated March 22, 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 McDonnell Douglas Corporation, P.O. 
Box 1771, Long Beach, California 90801-1771, Attention: Business 
Unit Manager, Technical Administrative Support, Dept. L51, M.C. 2-
98. Copies may be inspected at the FAA, Transport Airplane 
Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at 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.
    (f) This amendment becomes effective on May 2, 1995.

    Issued in Renton, Washington, on April 5, 1995.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 95-8826 Filed 4-14-95; 8:45 am]
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