[Federal Register Volume 61, Number 57 (Friday, March 22, 1996)]
[Proposed Rules]
[Pages 11789-11790]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-6931]



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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 95-NM-199-AD]


Airworthiness Directives; McDonnell Douglas Model DC-10 Series 
Airplanes and 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 certain McDonnell Douglas Model 
DC-10 series airplanes, and KC-10A (military) airplanes. This proposal 
would require high frequency eddy current inspection(s) to detect 
cracks in the secondary pivot support of the horizontal stabilizer, and 
various follow-on actions, if necessary. This proposal is prompted by 
reports of crack development in the secondary pivot support of the 
horizontal stabilizer due to fatigue. The actions specified by the 
proposed AD are intended to prevent such fatigue cracking, which could 
result in reduced structural integrity of the horizontal stabilizer 
and, subsequently, lead to reduced controllability of the airplane.

DATES: Comments must be received by May 17, 1996.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 95-NM-199-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, 3855 Lakewood Boulevard, 
Long Beach, California 90846, Attention: Technical Publications 
Business Administration, Department C1-L51 (2-60). 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, 3960 Paramount 
Boulevard, Lakewood, California.

FOR FURTHER INFORMATION CONTACT: Ron Atmur, Aerospace Engineer, 
Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification 
Office, 3960 Paramount Boulevard, Lakewood, California 90712; telephone 
(310) 627-5224; 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 95-NM-199-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. 95-NM-199-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received reports of crack development in the secondary 
pivot support of the horizontal stabilizer on several McDonnell Douglas 
Model DC-10 series airplanes. These airplanes had accumulated between 
37,738 and 57,029 total flight hours and between 13,831 and 32,313 
total flight cycles. The cause of such cracking has been attributed to 
fatigue. Fatigue cracking in the secondary pivot support of the 
horizontal stabilizer, if not detected and corrected in a timely 
manner, could result in reduced structural integrity of the horizontal 
stabilizer; this situation subsequently could lead to reduced 
controllability of the airplane.
    The FAA has reviewed and approved McDonnell Douglas DC-10 Service 
Bulletin 53-167, Revision 1, dated February 15, 1995, which describes 
procedures for high frequency eddy current (HFEC) inspection(s) to 
detect cracks in the secondary pivot support of the horizontal 
stabilizer. For cases where no cracks are detected during inspection, 
the service bulletin describes procedures for either conducting 
repetitive inspections, or installing a preventative modification. The 
preventative modification entails cold working holes in angles and 
installing angles on pivot supports. For cases where any crack is 
detected during inspection, the service bulletin describes procedures 
for either repairing the cracked area (temporary repair) and follow-on 
actions, or replacing the secondary pivot support of the horizontal 
stabilizer with a new secondary pivot support (permanent repair). 
Replacement of the affected secondary pivot support will ensure the 
structural integrity of the horizontal stabilizer, and will eliminate 
the need for repetitive inspections.
    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 HFEC inspection(s) to detect cracks in the 
secondary pivot support of the horizontal stabilizer. The proposed AD 
would also require repair of the cracked area and follow-on actions, or 
replacement of the cracked secondary pivot support of the horizontal 
stabilizer with a new secondary pivot support. Such replacement would 
constitute

[[Page 11790]]
terminating action for the repetitive inspections. The actions would be 
required to be accomplished in accordance with the service bulletin 
described previously.
    There are approximately 376 McDonnell Douglas Model DC-10 series 
airplanes and KC-10A (military) airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 230 airplanes of U.S. registry 
would be affected by this proposed AD, that it would take approximately 
5 work hours per airplane to accomplish the proposed actions, and that 
the average labor rate is $60 per work hour. Based on these figures, 
the cost impact of the proposed AD on U.S. operators is estimated to be 
$69,000, or $300 per airplane, per inspection cycle.
    The 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 USC 106(g) 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

McDonnell Douglas: Docket 95-NM-199-AD.

    Applicability: Model DC-10-10, -15, -30, and -40 series 
airplanes, and KC-10A (military) airplanes; as listed in McDonnell 
Douglas DC-10 Service Bulletin 53-167, Revision 1, dated February 
15, 1995; certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
otherwise modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must request approval for an 
alternative method of compliance in accordance with paragraph (d) of 
this AD. The request should include an assessment of the effect of 
the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent fatigue cracking in the secondary pivot support of 
the horizontal stabilizer, which could result in reduced structural 
integrity of the horizontal stabilizer and, subsequently, lead to 
reduced controllability of the airplane, accomplish the following:
    (a) Prior to the accumulation of 10,000 total landings, or 
within 3,000 landings after the effective date of this AD, whichever 
occurs later, perform a high frequency eddy current (HFEC) 
inspection to detect cracks in the secondary pivot support of the 
horizontal stabilizer, in accordance with McDonnell Douglas DC-10 
Service Bulletin 53-167, Revision 1, dated February 15, 1995.
    (b) If no cracks are detected during the HFEC inspection 
required by paragraph (a) of this AD, accomplish paragraph (b)(1) of 
this AD until paragraph (b)(2) of this AD is accomplished.
    (1) Repeat the HFEC inspection thereafter at intervals not to 
exceed 10,000 landings.
    (2) Accomplishment of the preventative modification in 
accordance with Condition I (no cracks), Option 2, of the service 
bulletin constitutes terminating action for the repetitive 
inspection requirements of paragraph (b)(1) of this AD.
    (c) If any crack is detected during the HFEC inspection required 
by paragraph (a) or (b) of this AD, prior to further flight, 
accomplish either paragraph (c)(1) or (c)(2) of this AD.
    (1) Repair the crack in accordance with Paragraph (1) of 
Condition II (cracks), Option 1 (temporary repair), of the 
Accomplishment Instructions of the service bulletin. Within 300 
landings after accomplishing that repair, perform a visual 
inspection to detect cracks at the area of the repair, in accordance 
with the service bulletin.
    (i) If any crack is detected during the visual inspection 
required by paragraph (c)(1) of this AD, prior to further flight, 
repair it in accordance with a method approved by the Manager, Los 
Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane 
Directorate.
    (ii) Prior to 2,800 landings after accomplishing the HFEC 
inspection required by paragraph (a) of this AD, replace the 
secondary pivot support of the horizontal stabilizer with a new 
secondary pivot support, in accordance with Condition II (cracks), 
Option 2, of the service bulletin. Accomplishment of this 
replacement constitutes terminating action for the repetitive HFEC 
and visual inspection requirements of this AD.
    (2) Replace the secondary pivot support of the horizontal 
stabilizer with a new secondary pivot support, in accordance with 
Condition II (cracks), Option 2 (permanent repair), of the service 
bulletin. Accomplishment of this replacement constitutes terminating 
action for the repetitive HFEC and visual inspection requirements of 
this AD.
    (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.

    (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 March 18, 1996.
James V. Devany,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-6931 Filed 3-21-96; 8:45 am]
BILLING CODE 4910-13-U