[Federal Register Volume 60, Number 55 (Wednesday, March 22, 1995)]
[Rules and Regulations]
[Pages 15033-15035]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-6238]



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[[Page 15034]]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94-NM-149-AD; Amendment 39-9174; AD 95-06-04]


Airworthiness Directives; McDonnell Douglas Model DC-9-80 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to McDonnell Douglas Model DC-9-80 series airplanes, that 
requires inspection and replacement of certain suspect horizontal 
stabilizer primary trim motors. This amendment is prompted by an 
analysis which revealed that certain incorrectly manufactured motor 
shafts could fail prematurely and, in turn, cause the primary trim 
motor to fail. The actions specified by this AD are intended to prevent 
such failures of the primary trim motor, which could ultimately result 
in reduced controllability of the airplane.

DATES: Effective April 21, 1995.

    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of April 21, 1995.

ADDRESSES: The service information referenced in this AD may be 
obtained from McDonnell Douglas Corporation, P.O. Box 1771, Long Beach, 
California 90801-1771, Attention: Business Unit Manager, Technical 
Administrative support, Dept. L51, M.C. 2-98. This information may be 
examined at the Federal Aviation Administration (FAA), Transport 
Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, 
Washington; or at FAA, Los Angeles Aircraft Certification Office, 
Transport Airplane Directorate, 3960 Paramount Boulevard, Lakewood, 
California; or at the Office of the Federal Register, 800 North Capitol 
Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Walter Eierman, Aerospace Engineer, 
Systems & Equipment Branch, ANM-130L, Los Angeles Aircraft 
Certification Office, FAA, Transport Airplane Directorate, 3960 
Paramount Boulevard, Lakewood, California; telephone (310) 627-5336; 
fax (310) 627-5210.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to McDonnell Douglas Model DC-9-80 
series airplanes was published in the Federal Register on October 18, 
1994 (59 FR 52482). That action proposed to require inspecting the 
horizontal stabilizer primary trim motor to determine if the motor is 
one having a suspect serial number, and replacing the suspect motors.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the two comments received.
    Both commenters support the rule.
    As a result of recent communications with the Air Transport 
Association (ATA) of America, the FAA has learned that, in general, 
some operators may misunderstand the legal effect of AD's on airplanes 
that are identified in the applicability provision of the AD, but that 
have been altered or repaired in the area addressed by the AD. The FAA 
points out that all airplanes identified in the applicability provision 
of an AD are legally subject to the AD. If an airplane has been altered 
or repaired in the affected area in such a way as to affect compliance 
with the AD, the owner or operator is required to obtain FAA approval 
for an alternative method of compliance with the AD, in accordance with 
the paragraph of each AD that provides for such approvals. A note has 
been added to this final rule to clarify this requirement.
    The FAA has recently reviewed the figures it has used over the past 
several years in calculating the economic impact of AD activity. In 
order to account for various inflationary costs in the airline 
industry, the FAA has determined that it is necessary to increase the 
labor rate used in these calculations from $55 per work hour to $60 per 
work hour. The economic impact information, below, has been revised to 
reflect this increase in the specified hourly labor rate.
    After careful review of the available data, including the comments 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule with the changes previously 
described. The FAA has determined that these changes will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.
    There are approximately 26 Model DC-9-80 series airplanes of the 
affected design in the worldwide fleet. The FAA estimates that 13 
airplanes of U.S. registry will be affected by this AD, that it will 
take approximately .5 work hour per airplane to accomplish the required 
actions, and that the average labor rate is $60 per work hour. Based on 
these figures, the total cost impact of the AD on U.S. operators is 
estimated to be $390, or $30 per airplane.
    Replacement of suspect motors will require 4.5 work hours to 
accomplish, at an average labor charge of $60 per work hour. Required 
replacement parts will be provided by Sundstrand Electric Power Systems 
(the manufacturer of the horizontal stabilizer primary trim motors) at 
no charge to operators. Based on these figures, the total cost impact 
is estimated to be $3,510, or $270 per airplane.
    The total cost impact figure discussed above is based on 
assumptions that no operator has yet accomplished any of the 
requirements of this AD action, and that no operator would accomplish 
those actions in the future if this AD were not adopted.
    The regulations adopted herein will 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 final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this action (1) is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); and (3) 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 final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it may be obtained 
from the Rules Docket at the location provided under the caption 
ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends 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:

    [[Page 15035]] 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:

95-06-04  McDonnell Douglas: Amendment 39-9174. Docket 94-NM-149-AD.

    Applicability: Model DC-9-80 series airplanes; as listed in 
McDonnell Douglas MD-80 Alert Service Bulletin A27-342, dated August 
4, 1994; 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 use the authority 
provided in paragraph (b) to request approval from the FAA. This 
approval may address either no action, if the current configuration 
eliminates the unsafe condition; or different actions necessary to 
address the unsafe condition described in this AD. Such a request 
should include an assessment of the effect of the changed 
configuration on the unsafe condition addressed by this AD. In no 
case does the presence of any modification, alteration, or repair 
remove any airplane from the applicability of this AD.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent failure of the horizontal stabilizer primary trim 
motor, accomplish the following:
    (a) Within 6 months after the effective date of this AD, conduct 
a visual inspection of the horizontal stabilizer primary trim motor 
to determine if the motor is identified with one of the suspect 
serial numbers listed in McDonnell Douglas MD-80 Alert Service 
Bulletin A27-342, dated August 4, 1994. Conduct this inspection in 
accordance with the procedures specified in that service bulletin.
    (1) If the horizontal stabilizer primary trim motor is not 
identified with a suspect serial number, no further action is 
required by this AD.-
    (2) If the horizontal stabilizer primary trim motor is 
identified with a suspect serial number, prior to further flight, 
replace the motor in accordance with the service bulletin. -
    (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. -
    (d) The inspection and replacement shall be done in accordance 
with McDonnell Douglas MD-80 Alert Service Bulletin A27-342, dated 
August 4, 1994. This incorporation by reference was approved by the 
Director of the Federal Register in accordance with 5 U.S.C. 552(a) 
and 1 CFR part 51. Copies may be obtained from McDonnell Douglas 
Corporation, P.O. Box 1771, Long Beach, California 90801-1771, 
Attention: Business Unit Manager, Technical Administrative Support, 
Dept. L51, M.C. 2-98. Copies may be inspected at the FAA, Transport 
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or 
at FAA, Los Angeles Aircraft Certification Office, Transport 
Airplane Directorate, 3960 Paramount Boulevard, Lakewood, 
California; or at the Office of the Federal Register, 800 North 
Capitol Street, NW., suite 700, Washington, DC. -
    (e) This amendment becomes effective on April 21, 1995.

    Issued in Renton, Washington, on March 8, 1995.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 95-6238 Filed 3-21-95; 8:45 am]
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