[Federal Register Volume 59, Number 136 (Monday, July 18, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-17327]


[[Page Unknown]]

[Federal Register: July 18, 1994]


=======================================================================
-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94-NM-22-AD]

 

Airworthiness Directives; McDonnell Douglas Model DC-10 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: This document proposes the supersedure of an existing 
airworthiness directive (AD), applicable to all McDonnell Douglas Model 
DC-10-10, -10F, -30, and -30F series airplanes, that currently requires 
inspections to detect ice or snow accumulation on top of the fuselage 
and in the inlet of the number 2 engine, and removal of ice and snow 
accumulation. This action would add certain airplanes to the 
applicability of the rule and would limit the inspection requirement to 
only a certain group of airplanes. This proposal is prompted by the 
development of improved fan blades on certain engines and the 
identification of additional airplanes that are subject to the unsafe 
condition. The actions specified by the proposed AD are intended to 
minimize damage to the number 2 engine due to ingestion of ice and 
snow.

DATES: Comments must be received by September 7, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 94-NM-22-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, Department 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.

FOR FURTHER INFORMATION CONTACT: Raymond 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 rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 94-NM-22-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. 94-NM-22-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA issued AD 75-04-11, amendment 39-2094, applicable to all 
McDonnell Douglas Model DC-10-10, -10F, -30, and -30F series airplanes, 
to require inspection to detect ice and snow accumulation on top of the 
fuselage and in the inlet of the number 2 engine, and removal of ice 
and snow. That action was prompted by reports from operators of Model 
DC-10 series airplanes that ice was ingested into the number 2 engine. 
In these incidents, the number 2 engine on airplanes that had been 
parked during icing conditions ingested ice and sustained damage 
shortly after the engine was started. The requirements of that AD are 
intended to prevent damage to the number 2 engine due to ingestion of 
ice and snow.
    Since the issuance of that AD, the General Electric (GE) Company 
has issued design changes to the GE Model CF6 series engines that 
include replacement of the gundrilled fan blades (that is, blades 
having radial lightening holes) with solid blades. The FAA has 
determined that in the event of excessive ice ingestion, these solid 
fan blades are less likely to result in an uncontained failure. 
Therefore, the FAA finds that the applicability of the existing rule 
must be revised to exclude airplanes equipped with these engines and 
fan blades from the AD requirement to inspect to detect ice and snow on 
top of the fuselage and in the inlet of the number 2 engine. 
(Similarly, Model DC-10-40 series airplanes equipped with Pratt and 
Whitney Model JT9D series engines having solid fan blades were excluded 
from the requirements of AD 75-04-11 since they, too, are not subject 
to the unsafe condition.)
    Further, since the issuance of AD 75-04-11, the FAA has determined 
that Model DC-10-15 series airplanes and Model KC-10A (military) 
airplanes are subject to the addressed unsafe condition since they 
utilize the same gundrilled blade engines as Model DC-10-10, -10F, -30, 
and -30F series airplanes, which are subject to the requirements of AD 
75-04-11 and are also susceptible to ice and snow ingestion into the 
number 2 engine. Therefore, the FAA finds that the applicability of the 
existing rule must be expanded to include Model DC-10-15 series 
airplanes and Model KC-10A (military) airplanes.
    Ingestion of ice and snow into the number 2 engine could result in 
damage to that engine.
    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 75-04-11 to require inspections to 
detect ice and snow accumulation on top of the fuselage and in the 
inlet of the number 2 engine, and removal of ice and snow. The 
applicability of this proposal would be revised to include all Model 
DC-10-10, -10F, -30, -30F, and -15 series airplanes and Model KC-10A 
(military) airplanes, equipped with GE Model CF6 series turbofan 
engines having gundrilled blades.
    Additionally, paragraph (b) of AD 75-04-11, which relates to making 
``appropriate maintenance record entries'' after accomplishing the 
requirements of the AD, has not been reiterated in this proposed AD 
since those requirements are redundant of the requirements contained in 
sections 43.9 (``Content, form, and disposition of maintenance, 
preventive maintenance, rebuilding, and alteration records'') and 43.11 
(``Content, form, disposition of records for inspections . . .'') of 
the Federal Aviation Regulations (14 CFR 43.9 and 43.11). As such, 
operators are not relieved from the requirement to make appropriate 
entries in their maintenance records.
    There are approximately 379 McDonnell Douglas Model DC-10-10, -10F, 
-30, -30F, and -15 series airplanes and Model KC-10A (military) 
airplanes of the affected design in the worldwide fleet. The FAA 
estimates that 226 airplanes of U.S. registry would be affected by this 
proposed AD.
    The inspections that were previously required by AD 75-04-11, and 
retained in this AD, take approximately 1 work hour per airplane to 
accomplish, at an average labor rate of $55 per work hour. Based on 
these figures, the total cost impact of the inspection requirement on 
U.S. operators is estimated to be $12,430, or $55 per airplane, per 
inspection. This proposal would only add the cost of inspections for 
the operators of Model KC-10A (military) airplanes. Currently, there 
are no Model DC-10-15 series airplanes of U.S. registry that would be 
affected by this proposal.
    For operators of Model DC-10-10, -10F, -30, and -30F series 
airplanes having all solid fan blades in the number 2 engine position, 
the economic burden would be reduced since the previous requirement to 
inspect these airplanes in accordance with the existing AD would be 
eliminated by this proposal. However, this does not relieve operators 
of the responsibility to comply with the requirements of sections 
91.527 (``Operating in icing conditions'') and 121.629 (``Operation in 
icing conditions''--air carriers) of the Federal Aviation Regulations 
(14 CFR 91.527 and 121.629).
    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 removing amendment 39-2094, and by 
adding a new airworthiness directive (AD), to read as follows:

McDonnell Douglas: Docket 94-NM-22-AD. Supersedes AD 75-04-11, 
Amendment 39-2094.

    Applicability: Model DC-10-10, -10F, -30, -30F, and -15 series 
airplanes, and Model KC-10A (military) airplanes, on which the 
number 2 engine is a General Electric Model CF6 series turbofan 
engine having one or more gundrilled fan blades installed, including 
but not limited to part numbers 9010M33 and 9137M39; certificated in 
any category.
    Compliance: Required as indicated, unless accomplished 
previously. To prevent possible damage to the number 2 engine due to 
ingestion of ice and snow, accomplish the following:
    (a) As of the effective date of this AD, prior to starting the 
number 2 engine on any airplane that has been parked during icing 
conditions (freezing rain, snow, sleet) for any period of time 
during which ice or snow may have accumulated on the airplane in the 
area of the number 2 engine, inspect to detect ice and snow 
accumulation on top of the fuselage and in the inlet of the number 2 
engine. If ice or snow accumulation is found, prior to further 
flight, remove the ice or snow accumulation.

    Note 1: Guidelines for inspection and safeguarding the aircraft 
are contained in these documents:

Douglas All Operators Letter (AOL) 10-546, dated January 11, 1974
Douglas AOL 10-673, dated August 7, 1974
DC-10 Airplane Maintenance Manual, Chapter 12-31-01

    (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 2: 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 
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 July 12, 1994.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-17327 Filed 7-15-94; 8:45 am]
BILLING CODE 4910-13-U