[Federal Register Volume 59, Number 139 (Thursday, July 21, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-17765]


[[Page Unknown]]

[Federal Register: July 21, 1994]


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DEPARTMENT OF TRANSPORTATION

14 CFR Part 39

[Docket No. 94-NM-62-AD]

 

Airworthiness Directives; McDonnell Douglas Model DC-10-30 and -
30F Series 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 certain McDonnell Douglas Model 
DC-10-30 and -30F series airplanes. This proposal would require 
replacement of cargo door latch spool fitting attach bolts fabricated 
from H-11 steel with Inconel bolts. This proposal is prompted by a 
report of a broken latch spool fitting attach bolt found on a cargo 
door on a Model DC-9 series freighter airplane. The actions specified 
by the proposed AD are intended to prevent inadvertent opening of a 
cargo door while the airplane is in flight, and subsequent loss of 
pressurization and reduced controllability of the airplane.

DATES: Comments must be received by October 10, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 94-NM-62-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. LS1, 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: Maureen Moreland, Aerospace Engineer, 
Airframe Branch, ANM-121L, FAA, Transport Airplane Directorate, Los 
Angeles Aircraft Certification Office, 3229 East Spring Street, Long 
Beach, California 90806-2425; telephone (310) 988-5238; 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-62-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-62-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On April 26, 1991, the FAA issued AD 91-10-07, amendment 39-6991 
(56 FR 21268), applicable to McDonnell Douglas Model DC-10 series 
airplanes, manufacturer's fuselage numbers 1 through 379 inclusive. 
That AD requires inspection of the cargo door latch spool fitting 
attach bolts fabricated from H-11 steel and replacement of those bolts 
with Inconel bolts. That action was prompted by a report of a broken 
latch spool fitting attach bolt found on a cargo door on a Model DC-9 
series freighter airplane. Broken bolts could jeopardize the integrity 
of the door locking capability. The requirements of AD 91-10-07 are 
intended to prevent loss of pressurization and reduced controllability 
of the aircraft due to inadvertent opening of a cargo door while the 
airplane is in flight.
    Since the issuance of AD 91-10-07, the manufacturer has informed 
the FAA that cargo door latch spool fitting attach bolts fabricated 
from H-11 steel also were installed on 8 additional Model DC-10 
production airplanes. Therefore, these 8 airplanes are subject to the 
same unsafe condition as addressed by that AD.
    The FAA has reviewed and approved McDonnell Douglas DC-10 Alert 
Service Bulletin A52-212, Revision 4, dated November 3, 1993, that 
describes procedures for replacement of the H-11 cargo door latch spool 
fitting attach bolts and associated hardware with Inconel bolts and 
associated hardware. Replacing the existing H-11 material bolts and 
associated hardware with new bolts made from Inconel material and 
associated hardware will eliminate the possibility of stress corrosion 
failures.
    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 replacement of H-11 cargo door latch spool 
fitting attach bolts with Inconel bolts on 8 Model DC-10-30 and -30F 
series airplanes. The actions would be required to be accomplished in 
accordance with the alert service bulletin described previously.

    Note: The FAA's normal policy is that, when an AD requires a 
substantive change, such as a change in its applicability, the 
``old'' AD is superseded by being removed from the system and a new 
AD added. In the case of this AD action, the FAA normally would have 
proposed superseding AD 91-10-07 to expand its applicability to 
include the 8 additional airplanes. However, in reconsideration of 
the entire fleet size that would be affected by such a supersedure 
action, and the consequent workload associated with revising 
maintenance record entries, the FAA has determined that a less 
burdensome approach is to issue a separate AD applicable only to the 
8 airplanes. This AD does not supersede AD 91-10-07; airplanes 
listed in the applicability of AD 91-10-07 continue to be required 
to comply with the requirements of that AD. This proposed AD is a 
separate AD action, and would be applicable only to eight airplanes 
listed in the alert service bulletin described above.

    There are 8 Model DC-10 series airplanes of the affected design in 
the worldwide fleet. The FAA estimates that 6 airplanes of U.S. 
registry would be affected by this proposed AD, that it would take 
approximately 86 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 $10,682 per airplane. Based on these 
figures, the total cost impact of the proposed AD on U.S. operators is 
estimated to be $92,472, or $15,412 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: 94-NM-62-AD.

    Applicability: Model DC-10-30 and -30F series airplanes having 
fuselage numbers 409, 412, 416, 419, 422, 433, 434, and 435; 
certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent inadvertent opening of a cargo door while the 
airplane is in flight, and subsequent loss of pressurization and 
reduced controllability of the airplane, accomplish the following:
    (a) Within 2 years after the effective date of this AD, replace 
all H-11 cargo door latch spool fitting attach bolts with Inconel 
bolts, in accordance with McDonnell Douglas DC-10 Alert Service 
Bulletin A52-212, Revision 4, dated November 3, 1993.
    (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 15, 1994.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-17765 Filed 7-20-94; 8:45 am]
BILLING CODE 4910-13-U