[Federal Register Volume 59, Number 143 (Wednesday, July 27, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-18195]


[[Page Unknown]]

[Federal Register: July 27, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket Number 94-NM-70-AD]

 

Airworthiness Directives; McDonnell Douglas Model DC-10 Series 
Airplanes and Model KC-10A (Military) 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 all McDonnell Douglas Model DC-10 
series airplanes and KC-10A (military) airplanes. This proposal would 
require modification of the fuel crossfeed dump shutoff system. This 
proposal is prompted by an FAA determination that, in the event of a 
failure of the number 2 bus tie relay and the subsequent loss of 
electrical power source of the number 2 engine, an all-engine flameout 
event could occur due to fuel starvation during or shortly after a fuel 
dumping operation. The actions specified by the proposed AD are 
intended to prevent loss of the fuel crossfeed dump shutoff system due 
to a failure of the number 2 DC bus electrical relay and the subsequent 
loss of electrical power source of the number 2 engine.

DATES: Comments must be received by September 19, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket Number 94-NM-70-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, P.O. Box 1771, Long Beach, 
California 90801-1771, Attention: Business Unit Manager, Technical 
Administrative Support, Dept. L51, M.C. 2-98. 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, 3229 East Spring Street, 
Long Beach, California 90806-2425.

FOR FURTHER INFORMATION CONTACT: Ray Vakili, Aerospace Engineer, 
Propulsion Branch, ANM-141L, FAA, Transport Airplane Directorate, Los 
Angeles Aircraft Certification Office, 3229 East Spring Street, Long 
Beach, California 90806-2425; telephone (310) 988-5262; fax (310) 988-
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 94-NM-70-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 Number 94-NM-70-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On October 1, 1992, the FAA issued AD 92-22-06, amendment 39-8392, 
(57 FR 47570, October 19, 1992), applicable to all McDonnell Douglas 
Model MD-11 airplanes, Model DC-10 series airplanes, and Model KC-10A 
(military) airplanes. That AD requires revising the Airplane Flight 
Manual (AFM) to include information to specify that electrical 
malfunctions may render the automatic fuel dump termination feature 
inoperative. That action was prompted by an incident in which the 
automatic fuel crossfeed dump shutoff system became inoperative, and 
fuel was dumped below the minimum allowable level. Dumping fuel below 
the minimum allowable level could lead to an all-engine-out condition.
    Since issuance of that AD, an in-depth review has revealed that the 
fuel dump shutoff system on Model DC-10 series airplanes and Model KC-
10A airplanes is such that, in the event of a failure of the number 2 
bus tie relay and the subsequent loss of electrical power source of the 
number 2 engine, an all-engine flameout event could occur due to fuel 
starvation during or shortly after fuel dumping operations. This 
condition, if not corrected, could render the fuel crossfeed dump 
shutoff system inoperable due to a failure of the number 2 DC bus 
electrical relay and the subsequent loss of the number 2 electrical 
power source.
    The FAA has reviewed and approved McDonnell Douglas DC-10 Service 
Bulletin 28-208, dated April 14, 1994, that describes procedures for 
modification of the fuel crossfeed dump shutoff system. This 
modification provides isolation of the engine fuel system, which 
entails installation of new fuel relays and, for certain airplanes, 
relocation of existing relays. Further, this modification also revises 
the electrical wiring for the fuel crossfeed dump shutoff system to 
provide redundant electrical power sources, which minimizes the 
possibility of system loss in the event of a number 2 engine shutdown.
    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 modification of the fuel crossfeed dump 
shutoff system. The actions would be required to be accomplished in 
accordance with the service bulletin described previously. 
Accomplishment of this modification will terminate the requirement 
imposed by paragraph (b) of AD 92-22-06 to revise the FAA-approved AFM, 
which cautioned that electrical malfunctions may render the automatic 
fuel dump termination feature inoperative.

    [Note: On March 23, 1994, the FAA issued AD 94-07-07, amendment 
39-8865 (59 FR 15853, April 5, 1994), applicable to certain Model 
MD-11 and MD-11F airplanes, to require a similar modification to 
terminate the requirement imposed by paragraph (a) of AD 92-22-06.]

    There are approximately 425 Model DC-10 series airplanes and KC-10A 
(military) airplanes of the affected design in the worldwide fleet. The 
FAA estimates that 221 airplanes of U.S. registry would be affected by 
this proposed AD, that it would take approximately 9 work hours per 
airplane to accomplish the proposed actions, and that the average labor 
rate is $55 per work hour. Required parts would cost approximately 
$1,560 per airplane. Based on these figures, the total cost impact of 
the proposed AD on U.S. operators is estimated to be $454,155, or 
$2,055 per airplane.
    The total 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 AD were not adopted.
    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. 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:

McDonnell Douglas: Docket 94-NM-70-AD.

    Applicability: All Model DC-10 series airplanes and KC-10A 
(military) airplanes, certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent loss of the fuel dump system shutoff due to a failure 
of the number 2 DC bus electrical relay and the subsequent loss of 
electrical power source of the number 2 engine, accomplish the 
following:
    (a) Within 24 months after the effective date of this AD, modify 
the fuel crossfeed dump shutoff system in accordance with McDonnell 
Douglas DC-10 Service Bulletin 28-208, dated April 14, 1994. 
Accomplishment of the modification constitutes terminating action 
for the revisions to the Airplane Flight Manual (AFM) required by 
paragraph (b) of AD 92-22-06, amendment 39-8392.
    (b) 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: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Los Angeles ACO.

    (c) 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.

    Issued in Renton, Washington, on July 20, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-18195 Filed 7-26-94; 8:45 am]
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