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[Federal Register Volume 63, Number 123 (Friday, June 26, 1998)]
[Proposed Rules]
[Pages 34832-34833]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-17007]

[[Page 34832]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-166-AD]
RIN 2120-AA64

Airworthiness Directives; McDonnell Douglas Model DC-9-80 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 adoption of a new airworthiness 
directive (AD) that is applicable to certain McDonnell Douglas Model 
DC-9-80 series airplanes, and Model MD-88 airplanes. This proposal 
would require a one-time inspection to detect corrosion of the lug 
bores and the surface of the hinge plates of the vertical-to-horizontal 
stabilizer; and corrective actions, if necessary. This proposal is 
prompted by reports of corrosion of the lug bores and the surface of 
the hinge plates of the vertical-to-horizontal stabilizer, apparently 
due to the improper brushing of cadmium on the hinge plates during 
manufacture. The actions specified by the proposed AD are intended to 
detect and correct corrosion of the lug bores and the surface of the 
hinge plates of the vertical-to-horizontal stabilizer, which could 
result in reduced structural integrity of the airplane.

DATES: Comments must be received by August 10, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 98-NM-166-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 The Boeing Company, Douglas Products Division, 3855 
Lakewood Boulevard, Long Beach, California 90846, Attention: Technical 
Publications Business Administration, Dept. 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: Brent Bandley, Aerospace Engineer, 
Airframe Branch, ANM-120L, FAA, Transport Airplane Directorate, Los 
Angeles Aircraft Certification Office, 3960 Paramount Boulevard, 
Lakewood, California 90712-4137; telephone (562) 627-5237; fax (562) 
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 98-NM-166-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-114, Attention: Rules 
Docket No. 98-NM-166-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received reports of corrosion on the lug bores and the 
surface of the hinge plates of the vertical-to-horizontal stabilizer on 
certain McDonnell Douglas Model DC-9-80 series airplanes, and Model MD-
88 airplanes. This corrosion occurred on airplanes that had accumulated 
between 15,000 and 30,000 total flight hours. Investigation has 
revealed that the hinge plates were apparently brushed with cadmium 
during the assembly drill out and line ream processes. During these 
manufacturing processes, it appears that the cadmium material became 
trapped between the mating hinge plates. Consequently, chemical action 
caused corrosion to occur around the lug bores. The corrosion has been 
attributed to the cadmium-brushed plates, which were not part of the 
approved type design. Such corrosion, if not detected and corrected in 
a timely manner, could result in reduced structural integrity of the 
airplane.

Explanation of Relevant Service Information

    The FAA has reviewed and approved McDonnell Douglas Service 
Bulletin MD80-55-054, dated March 3, 1998, which describes procedures 
for a one-time visual inspection to detect corrosion of the lug bores 
and the surface of the hinge plates of the vertical-to-horizontal 
stabilizer; and corrective actions, if necessary. Corrective actions 
include removal of corrosion that is within the limits specified in the 
Structural Repair Manual; and replacement of the hinge plates with new 
parts, if the corrosion exceeds the limits specified in the Structural 
Repair Manual. Accomplishment of the actions specified in the service 
bulletin is intended to adequately address the identified unsafe 
condition.

Explanation of Requirements of Proposed Rule

    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 a one-time inspection to detect corrosion of 
the lug bores and the surface of the hinge plates of the vertical-to-
horizontal stabilizer; and corrective actions, if necessary. The 
proposed AD also would require that operators report results of 
inspection findings (positive or negative) to the FAA.

Cost Impact

    There are approximately 1,059 airplanes of the affected design in 
the worldwide fleet. The FAA estimates that 706 airplanes of U.S. 
registry would be affected by this proposed AD. It would take 
approximately 117 work hours per airplane (which includes removal and 
installation) to accomplish the proposed inspection, at an average 
labor rate of $60 per work hour. Based on these figures, the cost 
impact of the proposed AD on U.S. operators is estimated to be 
$4,956,120, or $7,020 per airplane.

[[Page 34833]]

    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.

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), 40113, 44701.

Sec. 39.13  [Amended]

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

McDonnell Douglas: Docket 98-NM-166-AD.

    Applicability: Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 
(MD-83), and DC-9-87 (MD-87) series airplanes, and Model MD-88 
airplanes; as listed in McDonnell Douglas Service Bulletin MD80-55-
054, dated March 3, 1998; certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
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 (c) 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 detect and correct corrosion of the lug bores and the surface 
of the hinge plates of the vertical-to-horizontal stabilizer, which 
could result in reduced structural integrity of the airplane, 
accomplish the following:
    (a) Within 18 months after the effective date of this AD, 
perform a one-time visual inspection to detect corrosion of the lug 
bores and the surface of the hinge plates of the vertical-to-
horizontal stabilizer, in accordance with McDonnell Douglas Service 
Bulletin MD80-55-054, dated March 3, 1998.
    (1) Condition 1: If no corrosion is detected, no further action 
is required by this paragraph.
    (2) Condition 2: If any corrosion is detected that is within the 
limits specified in the Structural Repair Manual, prior to further 
flight, remove the corrosion in accordance with the service 
bulletin.
    (3) Condition 3: If any corrosion is detected that exceeds the 
limits specified in the Structural Repair Manual, prior to further 
flight, replace the hinge plates with new parts, in accordance with 
the service bulletin.
    (b) Within 10 days after accomplishing the inspection required 
by paragraph (a) of this AD, or within 10 days after the effective 
date of this AD, whichever occurs later, submit a report of the 
inspection results (both positive and negative findings) to the 
Manager, Los Angeles Aircraft Certification Office (ACO), FAA, 
Transport Airplane Directorate, 3960 Paramount Boulevard, Lakewood, 
California 90712-4137; fax (562) 627-5210. 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) 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.
    (d) 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 June 19, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-17007 Filed 6-25-98; 8:45 am]
BILLING CODE 4910-13-P
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