[Federal Register Volume 60, Number 173 (Thursday, September 7, 1995)]
[Proposed Rules]
[Pages 46544-46547]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-22209]



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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 94-NM-244-AD]


Airworthiness Directives; McDonnell Douglas Model DC-10 Series 
Airplanes and KC-10A (Military) Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Supplemental notice of proposed rulemaking; reopening of 
comment period.

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SUMMARY: This document revises an earlier proposed airworthiness 
directive (AD), which would have superseded an existing AD that is 
applicable to McDonnell Douglas Model DC-10 series airplanes and KC-10A 
(military) airplanes. The existing AD currently requires the 
implementation of a program of structural inspections to detect and 
correct fatigue cracking in order to ensure the continued airworthiness 
of these airplanes as they approach the manufacturer's original fatigue 
design life goal. The previously proposed action would have required, 
among other things, clarification of some Principle Structural Elements 
(PSE) and some non-destructive inspection (NDI) procedures. The 
previously proposed action was prompted by new data submitted by the 
manufacturer indicating that certain revisions to the program are 
necessary in order to clarify some PSE's and some NDI procedures. This 
action revises the proposed rule by deleting the requirement to perform 
visual inspections of Fleet Leader Operator Sampling (FLOS) PSE's. The 
actions specified by this proposed AD are intended to prevent fatigue 
cracking that could compromise the structural integrity of these 
airplanes.

DATES: Comments must be received by October 2, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 94-NM-244-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 90846-1771, Attention: Business Unit Manager, Contract Data 
Management C1-255 (35-22) This information may be examined at the FAA, 
Transport 

[[Page 46545]]
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at 
the FAA, Transport Airplane Directorate, Los Angeles Aircraft 
Certification Office, 3960 Paramount Boulevard, Lakewood, California.

FOR FURTHER INFORMATION CONTACT: Maureen Moreland, Aerospace Engineer, 
Airframe Branch, ANM-120L, FAA, Transport Airplane Directorate, Los 
Angeles Aircraft Certification Office, 3960 Paramount Boulevard, 
Lakewood, California 90712; telephone (310) 627-5238; fax (310) 627-
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-244-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-244-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to add an airworthiness directive (AD), applicable to 
McDonnell Douglas Model DC-10 series airplanes and KC-10A (military) 
airplanes, was published as a notice of proposed rulemaking (NPRM) in 
the Federal Register on April 17, 1995 (60 FR 19185). That NPRM would 
have required the implementation of a program of structural inspections 
to detect and correct fatigue cracking in order to ensure the continued 
airworthiness of these airplanes as they approach the manufacturer's 
original fatigue design life goal. That NPRM was prompted by new data 
submitted by the manufacturer indicating that certain revisions to the 
program are necessary in order to clarify some Principle Structural 
Elements (PSE) and some non-destructive inspection (NDI) procedures. 
Fatigue cracking in PSE's could compromise the structural integrity of 
these airplanes.
    Since the issuance of that NPRM, the FAA has received several 
comments from the manufacturer that have caused the FAA to reconsider 
its position on certain aspects of the proposed rule.

Changes to the Proposal

    McDonnell Douglas requests a revision of paragraph (b)(1) of the 
proposal for purposes of clarification. The manufacturer notes that the 
proposal states that operators are required to inspect aircraft before 
the threshold (Nth); however, the proposal does not clearly 
indicate that operators do not receive credit for these inspections in 
the Supplemental Inspection Document (SID) program, unless the aircraft 
has exceeded one-half of that threshold (Nth/2). The FAA concurs. 
The FAA has revised proposed paragraph (b)(1) to indicate that the 
inspections are to be performed prior to reaching the threshold 
(Nth), but no earlier than Nth/2.
    McDonnell Douglas also requests the deletion of the requirement to 
visually inspect fleet leader-operator sampling (FLOS) PSE's that are 
proposed in paragraph (b)(3). The manufacturer states that these 
requirements are redundant to those required by AD 92-22-09 R1, 
amendment 39-8590 (58 FR 32278, June 9, 1993), which requires the 
implementation of a corrosion prevention and control program to inspect 
all primary structures, including all PSE's.
    The FAA concurs. Paragraph (b)(3) of this supplemental NPRM [which 
was designated paragraph (b)(2) in the original NPRM] has been revised 
to indicate that these visual inspections are not required. However, 
the visual inspections that are part of the NDI procedures specified in 
Section 2 of Volume II of the SID are still required by this AD action. 
Additionally, paragraph (b)(4) from the originally proposed rule, which 
would have required general visual inspections, has been deleted from 
this supplemental NPRM since the requirement to perform visual 
inspections of FLOS PSE's are no longer necessary. Therefore, 
references to Section 4, ``Normal Maintenance Visual Inspections,'' of 
Volume II of the SID have been removed since those inspections are no 
longer required.
    Since these changes significantly revise the originally proposed 
rule, the FAA has determined that it is necessary to reopen the comment 
period to provide additional opportunity for public comment.
    Although other comments were received in response to the original 
NPRM, those comments, as well as any others received in response to 
this supplemental NPRM, will be addressed in the final rule.

Cost Impact

    There are approximately 419 Model DC-10 series airplanes and KC-10A 
(military) airplanes of the affected design in the worldwide fleet. The 
FAA estimates that 249 airplanes of U.S. registry and 13 U.S. operators 
would be affected by this proposed AD.
    Incorporation of the SID program into an operator's maintenance 
program, as required by AD 93-17-09 is estimated to necessitate 1,270 
work hours (per operator), at an average labor rate of $60 per work 
hour. Based on these figures, the cost to the 13 affected U.S. 
operators to incorporate the SID program is estimated to be $990,600.
    The incorporation of the revised procedures proposed in this AD 
action would require approximately 20 additional work hours per 
operator to accomplish, at an average labor rate of $60 per work hour. 
Based on these figures, the cost to the 13 affected U.S. operators to 
incorporate these revised procedures into the SID program into an 
operator's maintenance program is estimated to be $15,600.
    The recurring inspection costs, as required by AD 93-17-09, are 
estimated to be 365 work hours per airplane per year, at an average 
labor rate of $60 per work hour. Based on these figures, the recurring 
inspection costs required by AD 93-17-09 are estimated to be $21,900 
per airplane, or $5,453,100 for the affected U.S. fleet.
    Since no new recurring inspection procedures have been added to the 
program by this proposed AD action, there would be no additional 
economic burden on affected operators to perform additional recurrent 
inspections.
    Based on the above figures, the total cost impact of the proposed 
AD on U.S. operators is estimated to be $5,468,700 

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for the first year, and $5,453,100 for each year thereafter. These 
``total cost impact'' figures assume that no operator has yet 
accomplished any of the requirements of this AD. However, it can be 
reasonably assumed that a majority of the affected operators have 
already initiated the SID program (as required by AD 93-17-09).
    Additionally, the number of required work hours for each proposed 
inspection (and the SID program), as indicated above, is presented as 
if the accomplishment of those actions were to be conducted as ``stand 
alone'' actions. However, in actual practice, these actions for the 
most part will be accomplished coincidentally or in combination with 
normally scheduled airplane inspections and other maintenance program 
tasks. Therefore, the actual number of necessary additional work hours 
will be minimal in many instances. Further, any cost associated with 
special airplane scheduling can be expected to be minimal.

Regulatory Impact

    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. 106(g), 40101, 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing amendment 39-8680 (58 FR 
54949, October 25, 1993), and by adding a new airworthiness directive 
(AD), to read as follows:

McDonnell Douglas: Docket 94-NM-244-AD. Supersedes AD 93-17-09, 
Amendment 39-8680.

    Applicability: Model DC-10 series airplanes and KC-10A 
(military) airplanes, certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To ensure the continuing structural integrity of these 
airplanes, accomplish the following:
    (a) Within 6 months after November 24, 1993 (the effective date 
of AD 93-17-09, amendment 39-8680), incorporate a revision into the 
FAA-approved maintenance inspection program which provides for 
inspection(s) of the Principal Structural Elements (PSE's) defined 
in Section 2 of Volume I of McDonnell Douglas Report No. L26-012, 
``DC-10 Supplemental Inspection Document (SID),'' Revision 3, dated 
December 1992, in accordance with Section 2 of Volume III-92, dated 
October 1992, of the SID. The non-destructive inspection (NDI) 
techniques set forth in Section 2 and Section 4 of Volume II, 
Revision 3, dated December 1992, of the SID provide acceptable 
methods for accomplishing the inspections required by this 
paragraph. All inspection results (negative or positive) must be 
reported to McDonnell Douglas, in accordance with the instructions 
contained in Section 2 of Volume III-92, dated October 1992, of the 
SID. Information collection requirements contained in this 
regulation have been approved by the Office of Management and Budget 
(OMB) under the provisions of the Paperwork Reduction Act of 1980 
(44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number 
2120-0056.
    (1) For those Fleet Leader Operator Sampling (FLOS) PSE's that 
do not have a Normal Maintenance Visual Inspection specified in 
Section 4 of Volume II, Revision 3, dated December 1992, of the SID, 
the procedure for general visual inspection is as follows: Perform 
an inspection of the general PSE area for cleanliness, presence of 
foreign objects, security of parts, cracks, corrosion, and damage.
    (2) For PSE's 53.10.031E/.032E, 53.10.047E/.048E, and 
57.10.029E/.030E: The ENDDATE for these PSE's is October 1993. (For 
these PSE's disregard the June 1993 ENDDATE specified in Section 2 
of Volume III-92, dated October 1992, of the SID.)
    (b) Within 6 months after the effective date of this AD, replace 
the revision of the FAA-approved maintenance inspection program 
required by paragraph (a) of this AD with a revision that provides 
for inspection(s) of the PSE's defined in Section 2 of Volume I of 
McDonnell Douglas Report No. L26-012, ``DC-10 Supplemental 
Inspection Document (SID),'' Revision 5, dated October 1994, in 
accordance with Section 2 of Volume III-94, dated November 1994, of 
the SID. The NDI techniques set forth in Section 2 of Volume II, 
Revision 5, dated October 1994, of the SID provide acceptable 
methods for accomplishing the inspections required by this 
paragraph.
    (1) Prior to reaching the threshold (Nth), but no earlier 
than one-half of the threshold (Nth/2), specified for all PSE's 
listed in Volume III-94, dated November 1994, of the SID, inspect 
each PSE sample in accordance with the NDI procedures set forth in 
Section 2 of Volume II, Revision 5, dated October 1994. Thereafter, 
repeat the inspection for that PSE at intervals not to exceed DNDI/2 
of the NDI procedure that is specified in Volume III-94, dated 
November 1994, of the SID.
    (2) This AD does not require visual inspections of FLOS PSE's on 
airplanes listed in Volume III-94, dated November 1994, of the SID 
planning data at least once during the specified inspection 
interval, in accordance with Section 2 of Volume III-94, dated 
November 1994, of the SID.
    (3) For PSE's 53.10.055/.056E, 55.10.013/.014B, 53.10.005/.006E, 
53.10.031/.032E, 53.10.047/.048E, 57.10.029/.030E: The EDATE for 
these PSE's is June 1998. (For these PSE's, disregard the June 1996 
EDATE specified in Section 2, of Volume III-94, dated November 1994, 
of the SID.)
    (4) All inspection results (negative or positive) must be 
reported to McDonnell Douglas in accordance with the instructions 
contained in Section 2 of Volume III-94, dated November 1994, of the 
SID. Information collection requirements contained in this 
regulation have been approved by the Office of Management and Budget 
(OMB) under the provisions of the Paperwork Reduction Act of 1980 
(44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number 
2120-0056.
    (c) Any cracked structure detected during the inspections 
required by paragraph (a) or (b) of this AD must be repaired before 
further flight, in accordance with a method approved by the Manager, 
Los Angeles Aircraft Certification Office (ACO), FAA, Transport 
Airplane Directorate.

    Note 1: Requests for approval of any PSE repair that would 
affect the FAA-approved maintenance inspection program required by 
this AD should include a damage tolerance assessment for that PSE 
repair.

    (d) 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 ACO. 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. 

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    Note 3: Alternative methods of compliance previously granted for 
AD 93-17-09, amendment 39-8680, continue to be considered as 
acceptable alternative methods of compliance with this amendment.

    (e) 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 August 31, 1995.

Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.

[FR Doc. 95-22209 Filed 9-6-95; 8:45 am]

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