AD Amdt-39-12451

[Federal Register Volume 66, Number 188 (Thursday, September 27, 2001)]
[Rules and Regulations]
[Page 49510]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 01-24456]



[[Page 49509]]

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Part V





Department of Transportation





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Federal Aviation Administration



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14 CFR Part 39



Airworthiness Directives; McDonnell Douglas Model MD-11 Series 
Airplanes; Final Rule

Federal Register / Vol. 66, No. 188 / Thursday, September 27, 2001 / 
Rules and Regulations

[[Page 49510]]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NM-299-AD; Amendment 39-12451; AD 2001-17-09 R1]
RIN 2120-AA64


Airworthiness Directives; McDonnell Douglas Model MD-11 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; rescission.

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SUMMARY: This amendment rescinds Airworthiness Directive (AD) 2000-17-
09, which is applicable to certain McDonnell Douglas Model MD-11 series 
airplanes. That AD requires an inspection of the upper avionics circuit 
breaker panel at the main observer's station to detect damage of the 
wires and to verify the correct routing of the wire bundles; corrective 
actions, if necessary; and installation of a new clamp, spacer, and 
sta-straps. The requirements of that AD were intended to prevent 
chafing in the upper avionics circuit breaker panel of the main 
observer's station, which could result in arcing and consequent smoke 
and/or fire in the cockpit. Since the issuance of that AD, the FAA has 
determined that the improper procedures specified by the service 
bulletin referenced in that AD could lead to wiring pre-load conditions 
and consequent wire damage, and arcing in the upper avionics circuit 
breaker panel. Such conditions could result in arcing and consequent 
smoke and/or fire in the cockpit.

EFFECTIVE DATE: September 27, 2001.

FOR FURTHER INFORMATION CONTACT: Brett Portwood, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130L, FAA, Los Angeles Aircraft 
Certification Office, 3960 Paramount Boulevard, Lakewood, California 
90712-4137; telephone (562) 627-5350; fax (562) 627-5210.

SUPPLEMENTARY INFORMATION: On August 14, 2001, the Federal Aviation 
Administration (FAA) issued AD 2001-17-09, amendment 39-12400 (66 FR 
44041, August 22, 2001), applicable to certain McDonnell Douglas Model 
MD-11 series airplanes. That AD requires an inspection of the upper 
avionics circuit breaker panel at the main observer's station to detect 
damage of the wires and to verify the correct routing of the wire 
bundles; corrective actions, if necessary; and installation of a new 
clamp, spacer, and sta-straps. Chafing in the upper avionics circuit 
breaker panel of the main observer's station, could result in arcing 
and consequent smoke and/or fire in the cockpit.

Background

    During the comment period preceding the issuance of AD 2001-17-09, 
an operator submitted a letter stating its concern about the validity 
of the wiring procedures specified by Boeing Alert Service Bulletin 
MD11-24A179, Revision 01, dated October 31, 2000, which was cited in 
that AD. In response to that concern, the FAA consulted with the 
airplane manufacturer and was informed that the wiring procedures in 
the service bulletin were workable, and that the specified wire lengths 
were adequate. In light of this information, we determined that no 
change to the wire routing requirements of paragraph (a)(1)(ii) in the 
final rule was necessary.

Actions Since Issuance of Previous AD

    Following the issuance of AD 2001-17-09, the same operator 
contacted the FAA, informing us that the wiring procedures required by 
the AD per the Boeing service bulletin could cause wiring pre-load 
conditions. In response, we again consulted with Boeing to re-confirm 
their previous assessment. Boeing informed us that it had re-evaluated 
the procedures specified in the service bulletin and determined that, 
contrary to its original assessment, those procedures could actually 
cause wiring pre-load conditions and chafing.
    In light of this information, the FAA has determined that the 
procedures in the previously referenced Boeing service bulletin could 
lead to wiring pre-load conditions and consequent wire damage, and 
arcing in the upper avionics circuit breaker panel. Such conditions 
could result in arcing and consequent smoke and/or fire in the cockpit.

FAA's Determination

    Since accomplishment of the requirements of AD 2001-17-09 could 
cause conditions that may contribute to the identified unsafe 
condition, the FAA has determined that it is necessary to rescind that 
AD to prevent operators from performing the procedures included in the 
previously referenced Boeing service bulletin, which was cited in that 
AD. The FAA may consider further rulemaking to correct the original 
unsafe condition that prompted AD 2001-17-09.
    Since this action rescinds a requirement to perform improper 
procedures, it has no adverse economic impact and imposes no additional 
burden on any person. Therefore, notice and public procedures hereon 
are unnecessary and the rescission may be made effective upon 
publication in the Federal Register.

The Rescission

    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 an AD which removes amendment 
39-12400, to read as follows:

2001-17-09  R1 McDonnell Douglas: Amendment 39-12451. Docket No. 
2001-NM-299-AD. Rescinds AD 2001-17-09, Amendment 39-12400.

    Applicability: Model MD-11 series airplanes, as listed in Boeing 
Alert Service Bulletin MD11-24A179, Revision 01, dated October 31, 
2000; certificated in any category.
    This rescission is effective September 27, 2001.

    Issued in Renton, Washington, on September 25, 2001.
Vi L. Lipski,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-24456 Filed 9-26-01; 11:10 am]
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