[Federal Register Volume 59, Number 217 (Thursday, November 10, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-27853]


[[Page Unknown]]

[Federal Register: November 10, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 94-NM-92-AD]

 

Airworthiness Directives; McDonnell Douglas Model DC-9, DC-9-80, 
and C-9 (Military) Series Airplanes, and Model MD-88 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the supersedure of an existing 
airworthiness directive (AD), applicable to McDonnell Douglas Model DC-
9, DC-9-80, and C-9 (military) series airplanes, and Model MD-88 
airplanes, that currently requires certain inspections and structural 
modifications. This action would require additional inspections and 
structural modifications. This proposal is prompted by an evaluation 
conducted by the Airworthiness Assurance Working Group (AAWG), Model 
DC-9/MD-80 Task Group, which identified additional modifications for 
mandatory action. The actions specified by the proposed AD are intended 
to prevent degradation in the structural capabilities of the affected 
airplanes. This action also reflects the FAA's decision that long term 
continued operational safety should be assured by actual modification 
of the airframe, where feasible, rather than only by repetitive 
inspections for known service problems.

DATES: Comments must be received by December 23, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 94-NM-92-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: David Y. J. Hsu, Aerospace Engineer, 
Airframe Branch, ANM-122L, FAA, Transport Airplane Directorate, Los 
Angeles Aircraft Certification Office, 3229 East Spring Street, Long 
Beach, California 90806-2425; telephone (310) 988-5323; 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-92-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-92-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On August 6, 1990, the FAA issued AD 90-18-03, amendment 39-6701 
(55 FR 34704, August 24, 1990), applicable to Model DC-9, DC-9-80, and 
C-9 (military) series airplanes, and Model MD-88 airplanes, to require 
certain inspections and structural modifications. That action was 
prompted by reports of incidents involving fatigue cracking, corrosion, 
and stress corrosion cracking in transport category airplanes that are 
approaching or have exceeded their economic design goal. These 
incidents have jeopardized the airworthiness of the affected airplanes. 
The requirements of that AD are intended to prevent degradation in the 
structural capabilities of the affected airplanes.
    Since the issuance of that AD, the Airworthiness Assurance Working 
Group (AAWG), Model DC-9/MD-80 Task Group, comprised of representatives 
from operators of Model DC-9/MD-80 series airplanes, the manufacturer, 
and the FAA, has completed its review of certain service bulletins that 
are applicable to aging Model DC-9/MD-80 series airplanes. The Task 
Group has recommended these service bulletins for mandatory inspection 
and structural modification in order to reduce the potential for major 
structural failure of those airplanes.
    Consequently, McDonnell Douglas has issued Revision B to Report No. 
MDC K1572, ``DC-9/MD80 Aging Aircraft Service Action Requirements 
Document,'' dated January 15, 1993. The Task Group's most recent 
recommendations for mandatory actions are contained in Tables 2.3, 2.4, 
and 3.1 of that document. (The actions contained in Tables 2.1 and 2.2 
were made mandatory by AD 90-18-03.) The FAA has reviewed and approved 
that document. Tables 2.3 and 2.4 of the document reference the 
following service bulletins:
    1. One service bulletin that describes inspections and modification 
of the slat drive mechanism;
    2. Four service bulletins that describe inspections and 
modifications of the doors;
    3. Eleven service bulletins that describe inspections and 
modifications of the fuselage;
    4. Four service bulletins that describe inspections and 
modifications of the horizontal stabilizers;
    5. Two service bulletins that describe inspections and 
modifications of the wings;
    6. One service bulletin that describes inspections and modification 
of the engine thrust reverser system;
    7. One service bulletin that describes inspections and modification 
of the nose gear steering;
    8. Two service bulletins that describe inspections and 
modifications of the engine pylon;
    9. One service bulletin that describes inspections and modification 
of the rudder; and
    10. Two service bulletins that describe inspections and 
modifications of the main landing gear structures.
    Table 3.1 of the document references the following service 
bulletins for mandatory inspections:
    1. One service bulletin that describes inspections of the doors;
    2. One service bulletin that describes inspections of the engine 
pylons; and
    3. Two service bulletins that describe inspections of the wings. 
(These two service bulletins were made mandatory by AD 90-18-03.) -
    The Task Group has also recommended, for mandatory modification, 
the actions contained in McDonnell Douglas DC-9 Service Bulletin 53-
230, Revision 1, dated January 12, 1993. The FAA has reviewed and 
approved this service bulletin, which describes procedures for 
installation of doublers and clips at the intersections of upper 
longerons/intercostals and fuselage frames between longerons 10L and 
10R at various overwing stations between Y=484.000 and Y=851.000, as 
applicable, depending upon series of the airplane. Accomplishment of 
these modifications would terminate the inspections required by AD 88-
24-08 R2, amendment 39-6469 (55 FR 1002, January 11, 1990), which 
requires external eddy current inspection to detect cracking of the 
fuselage skin and certain longerons, internal visual inspections of 
certain longerons, and repair of any findings of cracking. -
    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 90-18-03 to require additional 
structural modifications and inspections. The actions would be required 
to be accomplished in accordance with the document described 
previously. -
    There are approximately 892 Model DC-9 and C-9 (military) series 
airplanes of the affected design in the worldwide fleet. -
    The FAA estimates that 568 Model DC-9 and C-9 (military) series 
airplanes of U.S. registry were originally affected by AD 90-18-03. The 
requirements of that AD were estimated to take approximately 946 work 
hours to accomplish, at a current average labor rate of $55 per work 
hour. The cost for required modification kits was estimated to be 
$15,140 per airplane. Based on these figures, the FAA estimated that 
the total cost impact of AD 90-18-03 on U.S. operators of Model DC-9 
and C-9 (military) series airplanes would be $38,152,560, or $67,170 
per airplane, over the initial 4-year time period. (These figures do 
not include the cost of downtime, planning, set-up, familiarization, or 
tool acquisition.) -
    The FAA estimates that a total of 511 Model DC-9 and C-9 (military) 
series airplanes of U.S. registry would be affected by the new 
requirements specified in this proposed AD. The new additional 
requirements proposed by this AD action would take approximately 638 
additional work hours per airplane to accomplish, at an average labor 
rate of $55 per work hour. Required parts would cost an additional 
$37,027 per airplane. Based on these figures, the total additional cost 
impact of this proposed AD on U.S. operators is estimated to be 
$36,851,787, or $72,117 per airplane, over a 4-year time period. (These 
figures do not include the cost of downtime, planning, set-up, 
familiarization, and tool acquisition.) -
    There are approximately 1,090 Model DC-9-80 series airplanes and 
Model MD-88 airplanes of the affected design in the worldwide fleet. -
    The FAA estimates that 173 Model DC-9-80 series airplanes and Model 
MD-88 airplanes of U.S. registry were originally affected by AD 90-18-
03. The requirements of that AD were estimated to take approximately 47 
work hours to accomplish, at a current average labor rate of $55 per 
work hour. The cost for required modification kits was estimated to be 
$752 per airplane. Based on these figures, the FAA estimated that the 
total cost impact of AD 90-18-03 on U.S. operators of Model DC-9-80 
series airplanes and Model MD-88 airplanes would be $577,301, or $3,337 
per airplane, over the initial 4-year time period. (These figures do 
not include the cost of downtime, planning, set-up, familiarization, or 
tool acquisition.) -
    The FAA estimates that a total of 615 Model DC-9-80 series 
airplanes and Model MD-88 airplanes of U.S. registry would be affected 
by the new requirements specified in this proposed AD. This increase in 
the number of affected airplanes is due to various reasons, including 
transfer of ownership and the fact that additional airplanes have 
accumulated time-in-service since the issuance of AD 90-18-03 and have 
reached the threshold for modification/inspection. The new additional 
requirements proposed by this AD action would take approximately 13 
additional work hours per airplane to accomplish, at an average labor 
rate of $55 per work hour. Required parts would cost an additional $943 
per airplane. Based on these figures, the total additional cost impact 
of this proposed AD on U.S. operators is estimated to be $1,019,670, or 
$1,658 per airplane, over a 4-year time period. (These figures do not 
include the cost of downtime, planning, set-up, familiarization, or 
tool acquisition.) -
    The total cost impact figure discussed above is based on 
assumptions that no operator has yet accomplished the currently 
required or the newly proposed requirements of this AD action; however, 
it can reasonably be assumed that a majority of affected operators have 
already initiated the inspections and structural modifications required 
by AD 90-18-03 [retained in paragraphs (a) and (d) of this AD] and many 
may have already initiated the additional inspections and structural 
modifications proposed in this new AD action. -
    The number of required work hours, as indicated above, is presented 
as if the accomplishment of the actions proposed in this AD were to be 
conducted as ``stand alone'' actions. However, in actual practice, 
these actions for the most part would 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 would be minimal in many instances. Additionally, 
any costs associated with special airplane scheduling would be minimal. 
-
    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 39-6701 (55 FR 
34704, August 24, 1990), and by adding a new airworthiness directive 
(AD), to read as follows:

McDonnell Douglas: Docket 94-NM-92-AD. Supersedes AD 90-18-03, 
Amendment 39-6701.

    Applicability: Model DC-9-10, -20, -30, -40, -50 series 
airplanes; Model DC-9-81 (MD-81), -82 (MD-82), -83 (MD-83), and -87 
(MD-87) series airplanes; Model MD-88 airplanes; and C-9 (military) 
series airplanes; certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent structural failure, accomplish the following:
    (a) Within the threshold for inspections specified in the 
service bulletins listed in either Table 2.1 [for Model DC-9-10, -
20, -30, -40, -50, and C-9 (military) series airplanes], or Table 
2.2 [for Model DC-9-81, -82, -83, -87 (MD-81, -82, -83, -87), and 
Model MD-88 airplanes], as applicable, of McDonnell Douglas Report 
No. MDC K1572, ``DC-9/MD-80 Aging Aircraft Service Action 
Requirements Document,'' Revision A, dated June 1, 1990 (hereinafter 
referred to as ``SARD, Revision A''), or within one repetitive 
inspection period specified in those service bulletins after 
September 24, 1990 (the effective date of AD 90-18-03, Amendment 39-
6701), whichever occurs later: Inspect to detect cracks in 
accordance with those service bulletins. Repeat these inspections 
thereafter at the intervals specified in the service bulletins 
listed in either Table 2.1 [for Model DC-9-10, -20, -30, -40, -50, 
and C-9 (military) series airplanes], or Table 2.2 [for Model DC-9-
81, -82, -83, -87 (MD-81, -82, -83, -87), and Model MD-88 
airplanes], as applicable, of SARD, Revision A, until the applicable 
terminating modification required by paragraph (d) of this AD is 
accomplished.

    -Note 1: Paragraph (a) of this AD restates the requirements for 
an initial inspection and the repetitive inspections contained in 
paragraph A. of AD 90-18-03. Therefore, for operators who have 
previously accomplished at least the initial inspection in 
accordance with AD 90-18-03, paragraph (a) of this AD requires that 
the next scheduled inspection be performed within the specified 
repetitive inspection interval after the last inspection performed 
in accordance with paragraph A. of AD 90-18-03.

    -(b) Within the threshold for inspections specified in the 
service bulletins listed in Tables 2.3 and 3.1 [for Model DC-9-10, -
20, -30, -40, -50, and C-9 (military) series airplanes], or Table 
2.4 [for Model DC-9-81, -82, -83, -87 (MD-81, -82, -83, -87), and 
Model MD-88 airplanes], as applicable, of McDonnell Douglas Report 
No. MDC K1572, ``DC-9/MD-80 Aging Aircraft Service Action 
Requirements Document,'' Revision B, dated January 15, 1993 
(hereinafter referred to as ``SARD, Revision B''), or within one 
repetitive inspection period specified in those service bulletins 
after the effective date of this AD, whichever occurs later: Inspect 
to detect cracks in accordance with those service bulletins. Repeat 
these inspections thereafter at the intervals specified in the 
service bulletins listed in either paragraph (b)(1) or (b)(2) of 
this AD, as applicable, until the applicable terminating 
modification required by paragraph (e) of this AD is accomplished. -
    (1) For Model DC-9-10, -20, -30, -40, -50, and C-9 (military) 
series airplanes: The service bulletins listed in Tables 2.3 and 3.1 
of SARD, Revision B. Or -
    (2) For Model DC-9-81, -82, -83, -87 (MD-81, -82, -83, -87), and 
Model MD-88 airplanes: The service bulletins listed in Table 2.4 of 
SARD, Revision B. -
    (c) If any crack is found during any inspection required by this 
AD, prior to further flight, either accomplish the applicable 
terminating modification in accordance with paragraph (d) or (e) of 
this AD, or repair in accordance with a method approved by the 
Manager, Los Angeles Aircraft Certification Office (ACO), FAA, 
Transport Airplane Directorate.

    -Note 2: Detection of any discrepancy, other than cracking, 
necessitates appropriate corrective action in accordance with the 
provisions of part 43 of the Federal Aviation Regulations (14 CFR 
part 43).

    -(d) Prior to reaching the incorporation thresholds listed in 
either Table 2.1 [for Model DC-9-10, -20, -30, -40, -50, and C-9 
(military) series airplanes], or Table 2.2 [for Model DC-9-81, -82, 
-83, -87 (MD-81, -82, -83, -87), and Model MD-88 airplanes], as 
applicable, of SARD, Revision A or Revision B, or within 4 years 
after September 24, 1990 (the effective date of AD 90-18-03), 
whichever occurs later: Accomplish the structural modifications 
specified in the service bulletins listed in either Table 2.1 [for 
Model DC-9-10, -20, -30, -40, -50, and C-9 (military) series 
airplanes], or Table 2.2 [for Model DC-9-81, -82, -83, -87 (MD-81, -
82, -83, -87), and Model MD-88 airplanes], as applicable, of SARD, 
Revision A or Revision B. Accomplishment of these modifications 
constitutes terminating action for the applicable inspections 
required by paragraph (a) of this AD.

    -Note 3: Paragraph (d) of this AD restates the modification 
requirements of paragraph B. of AD 90-18-03. As allowed by the 
phrase, ``unless accomplished previously,'' if the requirements of 
paragraph B. of AD 90-18-03 have been accomplished previously, 
paragraph (d) of this AD does not require that they be repeated. -
    Note 4: The service bulletin revision levels listed under 
``Recommended Modification'' in either Table 2.1 [for Model DC-9-10, 
-20, -30, -40, -50, and C-9 (military) series airplanes], or Table 
2.2 [for Model DC-9-81, -82, -83, -87 (MD-81, -82, -83, -87), and 
Model MD-88 airplanes], as applicable, of SARD, Revision B, are 
acceptable revisions for modifications accomplished prior to 
September 24, 1994.

    -(e) Prior to reaching the incorporation thresholds listed in 
either Table 2.3 [for Model DC-9-10, -20, -30, -40, -50, and C-9 
(military) series airplanes], or Table 2.4 [for Model DC-9-81, -82, 
-83, -87 (MD-81, -82, -83, -87), and Model MD-88 airplanes], as 
applicable, of SARD, Revision B, or within 4 years after the 
effective date of this AD, whichever occurs later: Accomplish the 
structural modifications specified in the service bulletins listed 
in either Table 2.3 [for Model DC-9-10, -20, -30, -40, -50, and C-9 
(military) series airplanes], or Table 2.4 [for Model DC-9-81, -82, 
-83, -87 (MD-81, -82, -83, -87), and Model MD-88 airplanes], as 
applicable, of SARD, Revision B.
    Accomplishment of this modification constitutes terminating 
action for the applicable inspections required by paragraph (b) of 
this AD.

    -Note 5: The service bulletin revision levels listed under 
``Recommended Modification'' in either Table 2.3 [for Model DC-9-10, 
-20, -30, -40, -50, and C-9 (military) series airplanes], or Table 
2.4 [for Model DC-9-81, -82, -83, -87 (MD-81, -82, -83, -87), and 
Model MD-88 airplanes] of SARD, Revision B, are acceptable revisions 
for modifications accomplished prior to the effective date of this 
AD. -
    Note 6: The modifications required by paragraphs (d) and (e) of 
this AD do not terminate the inspection requirements of any other AD 
unless that AD specifies that any such modification constitutes 
terminating action for those specified inspection requirements.

    (f) For Model DC-9-10, -20, -30, -40, -50, and C-9 (military) 
series airplanes: Prior to the accumulation of 100,000 total 
landings, accomplish the modifications specified in McDonnell 
Douglas DC-9 Service Bulletin 53-230, Revision 1, dated January 12, 
1993. Accomplishment of these modifications constitute terminating 
action for the inspections required by AD 88-24-08 R2, amendment 39-
6469. -
    (g) Accomplishment of the modifications in accordance with the 
service bulletins listed in Tables 2.1 and 2.3 [for Model DC-9-10, -
20, -30, -40, -50, and C-9 (military) series airplanes], or Tables 
2.2 and 2.4 [for Model DC-9-81, -82, -83, -87 (MD-81, -82, -83, -
87), and Model MD-88 airplanes] of SARD, Revision A or B, terminates 
the individual inspection requirements of the applicable service 
bulletin. -
    (h) The requirements of this AD exclude the actions specified in 
the following McDonnell Douglas service bulletins that are 
referenced in the following tables of SARD, Revision A or B:

------------------------------------------------------------------------
    Table(s)-                         Service Bulletin                  
------------------------------------------------------------------------
2.1 and 2.2-.....  MD-80 Service Bulletin 53-186.                       
2.2-.............  MD-80 Service Bulletin 53-216                        
------------------------------------------------------------------------

    -(i) 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 7: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Los Angeles ACO.

    (j) Alternative methods of compliance previously granted for 
amendment AD 90-18-03, 39-6701 continue to be considered as 
acceptable alternative methods of compliance with this amendment.
    (k) 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 November 4, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-27853 Filed 11-9-94; 8:45 am]
BILLING CODE 4910-13-U