

[Federal Register: September 28, 2007 (Volume 72, Number 188)]
[Proposed Rules]               
[Page 55111-55113]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr28se07-31]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-29335; Directorate Identifier 2007-NM-045-AD]
RIN 2120-AA64

 
Airworthiness Directives; McDonnell Douglas Model DC-9-81 (MD-
81), DC-9-82 (MD-82), DC-9-83 (MD-83), DC-9-87 (MD-87), and MD-88 
Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for all McDonnell Douglas Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-
83 (MD-83), DC-9-87 (MD-87), and MD-88 airplanes. This proposed AD 
would require repetitive inspections for cracking of the overwing 
frames from stations 845 to 905 (MD-87 stations 731 to 791), left and 
right sides, and corrective actions if necessary. This proposed AD 
results from reports of cracked overwing frames. We are proposing this 
AD to detect and correct such cracking, which could sever the frame, 
increase the loading of adjacent frames, and result in damage to 
adjacent structure and loss of overall structural integrity of the 
airplane.

DATES: We must receive comments on this proposed AD by November 13, 
2007.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD.
     DOT Docket Web site: Go to http://dms.dot.gov and follow 

the instructions for sending your comments electronically.
     Government-wide rulemaking Web site: Go to http://www.regulations.gov
 and follow the instructions for sending your 

comments electronically.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590.
     Fax: (202) 493-2251.
     Hand Delivery: Room W12-140 on the ground floor of the 
West Building, 1200 New Jersey Avenue, SE., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    Contact Boeing Commercial Airplanes, Long Beach Division, 3855 
Lakewood Boulevard, Long Beach, California 90846, Attention: Data and 
Service Management, Dept. C1-L5A (D800-0024), for the service 
information identified in this proposed AD.

FOR FURTHER INFORMATION CONTACT: Roger Durbin, Aerospace Engineer, 
Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification 
Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; 
telephone (562) 627-5233; fax (562) 627-5210.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to submit any relevant written data, views, or 
arguments regarding this proposed AD. Send your comments to an address 
listed in the ADDRESSES section. Include the docket number ``FAA-2007-
29335; Directorate Identifier 2007-NM-045-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the proposed AD. We will 
consider all comments received by the closing date and may amend the 
proposed AD in light of those comments.
    We will post all comments we receive, without change, to http://dms.dot.gov
, including any personal information you provide. We will 

also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this proposed AD. Using the search function of 
that Web site, anyone can find and read the comments in any of our 
dockets, including the name of the individual who sent the comment (or 
signed the comment on behalf of an association, business, labor union, 
etc.). You may review DOT's complete Privacy Act Statement in the 
Federal Register published on April 11, 2000 (65 FR 19477-78), or you 
may visit http://dms.dot.gov.


Examining the Docket

    You may examine the AD docket on the Internet at http://dms.dot.gov
, or in person at the Docket Operations office between 9 

a.m. and 5 p.m., Monday through Friday, except Federal holidays. The 
Docket Operations office (telephone (800) 647-5527) is located on the 
ground floor of the West Building at the DOT street address stated in 
the ADDRESSES section. Comments will be available in the AD docket 
shortly after the Docket Management System receives them.

Discussion

    We have received a report indicating that four MD-80 operators 
reported six instances of cracked overwing frames. The reports indicate 
two failures at frame station 886 on the left side, three failures at 
frame station 886 on the right side, and one failure at frame station 
905 on the right side. The cracking occurred on airplanes that had 
accumulated between 25,965 and 40,612 total flight cycles. The cracks, 
which originate in the upper radius of the frame inboard tab just below 
the floor, were caused by fatigue. Frames at stations 845 and 864, 
although not reported to be cracked, are also susceptible to this type 
of failure. All of the noted frames are a part of MD-80 principal 
structural element (PSE) 53.80.005 (although the inspections that would 
be required by this proposed AD are not included in supplemental 
inspections already required for PSE 53.80.005). If not corrected, an 
undetected crack might sever the frame, which could increase the 
loading of adjacent frames, result in damage to adjacent structure, 
necessitate extensive repair, and ultimately lead to the loss of 
overall structural integrity of the airplane.

Relevant Service Information

    We have reviewed Boeing Alert Service Bulletin MD80-53A301, 
Revision 1, dated May 25, 2007. The service bulletin describes 
procedures for inspections, using general visual and high frequency 
eddy current methods, to detect cracking of the overwing frames from 
stations 845 to 905 (MD-87 stations 731 to 791), left and right sides. 
The service bulletin specifies repeating the inspections within 9,300 
flight cycles after any repair, within 20,000 flight cycles after any 
replacement, and at intervals not to exceed 9,300 flight cycles if no 
cracks are found. Corrective actions are done before further flight and 
include a blend out repair of cracks less than 0.125 inch deep, and 
replacement of any overwing frame with a crack 0.125 inch or deeper.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to exist or

[[Page 55112]]

develop on other airplanes of this same type design. For this reason, 
we are proposing this AD, which would require accomplishing the actions 
specified in the service information described previously.

Interim Action

    We consider this proposed AD interim action. The manufacturer is 
currently developing a modification that will address the unsafe 
condition identified in this proposed AD. Once this modification is 
developed, approved, and available, we may consider additional 
rulemaking.

Costs of Compliance

    There are about 1,189 airplanes of the affected design in the 
worldwide fleet. The following table provides the estimated costs for 
U.S. operators to comply with this proposed AD.

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                              Number of U.S.-
     Work hours       Average labor         Parts          Cost per airplane    registered        Fleet cost
                      rate per hour                                              airplanes
----------------------------------------------------------------------------------------------------------------
4..................             $80  None...............  $320, per                      670  $214,400, per
                                                           inspection cycle.                   inspection cycle.
----------------------------------------------------------------------------------------------------------------

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, Section 106, describes the 
authority of the FAA Administrator. Subtitle VII, Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We have determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would not 
have a substantial direct effect 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.
    For the reasons discussed above, I certify that the 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. 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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this proposed AD and placed it in the AD docket. See the 
ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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. The Federal Aviation Administration (FAA) amends Sec.  39.13 by 
adding the following new airworthiness directive (AD):

McDonnell Douglas: Docket No. FAA-2007-29335; Directorate Identifier 
2007-NM-045-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by November 
13, 2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to all McDonnell Douglas Model DC-9-81 (MD-
81), DC-9-82 (MD-82), DC-9-83 (MD-83), DC-9-87 (MD-87), and MD-88 
airplanes, certificated in any category.

Unsafe Condition

    (d) This AD results from reports of cracked overwing frames. We 
are issuing this AD to detect and correct such cracking, which could 
sever the frame, increase the loading of adjacent frames, and result 
in damage to adjacent structure and loss of overall structural 
integrity of the airplane.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified, unless the 
actions have already been done.

Inspections

    (f) Before the accumulation of 20,000 total flight cycles, or 
within 24 months after the effective date of this AD, whichever 
occurs later: Do general visual and high frequency eddy current 
inspections, and all applicable corrective actions, in accordance 
with the Accomplishment Instructions of Boeing Alert Service 
Bulletin MD80-53A301, Revision 1, dated May 25, 2007. Do the 
applicable corrective actions before further flight after 
accomplishing the inspections. Repeat the inspections thereafter at 
applicable intervals not to exceed those specified in paragraph 
1.E., ``Compliance,'' of the service bulletin.

Actions According to Previous Issue of Service Bulletin

    (g) Inspections and related investigative and corrective actions 
are also acceptable for compliance with the requirements of 
paragraph (f) of this AD if done before the effective date of this 
AD in accordance with Boeing Alert Service Bulletin MD80-53A301, 
dated January 9, 2007.

Alternative Methods of Compliance (AMOCs)

    (h)(1) The Manager, Los Angeles Aircraft Certification Office 
(ACO), FAA, has the authority to approve AMOCs for this AD, if 
requested in accordance with the procedures found in 14 CFR 39.19.
    (2) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Before using any approved AMOC on any airplane to which the AMOC 
applies, notify your appropriate principal inspector (PI) in the FAA 
Flight Standards District Office (FSDO), or lacking a PI, your local 
FSDO.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair required by this AD, if it is approved by an 
Authorized Representative for the Boeing Commercial Airplanes 
Delegation Option Authorization Organization who has been authorized 
by the Manager, Los Angeles ACO, to make those findings. For a 
repair

[[Page 55113]]

method to be approved, the repair must meet the certification basis 
of the airplane and 14 CFR 25.571, Amendment 45, and the approval 
must specifically refer to this AD.

    Issued in Renton, Washington, on September 21, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E7-19204 Filed 9-27-07; 8:45 am]

BILLING CODE 4910-13-P
