
[Federal Register Volume 78, Number 47 (Monday, March 11, 2013)]
[Rules and Regulations]
[Pages 15281-15283]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-05196]



[[Page 15281]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-0909; Directorate Identifier 2011-NM-027-AD; 
Amendment 39-17374; AD 2013-05-02]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for all The 
Boeing Company 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 AD was prompted by reports 
of cracks of the hinge bearing lugs of the center section ribs of the 
horizontal stabilizer. This AD requires repetitive high frequency eddy 
current (HFEC) inspections for cracking of the left and right rib hinge 
bearing lugs of the aft face of the center section of the horizontal 
stabilizer; measuring crack length and blending out cracks; and 
replacing the horizontal stabilizer center section rib, if necessary. 
We are issuing this AD to detect and correct cracking in the hinge 
bearing lugs of the horizontal stabilizer center section ribs, which 
could result in failure of the lugs, and consequent inability of the 
horizontal stabilizer to sustain the required limit loads and loss of 
control of the airplane.

DATES: This AD is effective April 15, 2013.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in the AD as of April 15, 
2013.

ADDRESSES: For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Data & Services Management, 
3855 Lakewood Boulevard, MC D800-0019, Long Beach, CA 90846-0001; 
telephone 206-544-5000, extension 2; fax 206-766-5683; Internet https://www.myboeingfleet.com. You may review copies of the referenced service 
information at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue SW., Renton, Washington. For information on the availability of 
this material at the FAA, call 425-227-1221.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this AD, the regulatory evaluation, 
any comments received, and other information. The address for the 
Docket Office (phone: 800-647-5527) is Document Management Facility, 
U.S. Department of Transportation, Docket Operations, M-30, West 
Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., 
Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Roger Durbin, Aerospace Engineer, 
Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification 
Office (ACO), 3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: 
562-627-5233; fax: 562-627-5210; email: roger.durbin@faa.gov.

SUPPLEMENTARY INFORMATION: 

Discussion

    We issued a supplemental notice of proposed rulemaking (SNPRM) to 
amend 14 CFR part 39 to include an airworthiness directive (AD) that 
would apply to the specified products. That SNPRM published in the 
Federal Register on September 11, 2012 (77 FR 55773). The original NPRM 
(76 FR 53346, August 26, 2011) proposed to require repetitive high 
frequency eddy current (HFEC) inspections for cracking of the left and 
right rib hinge bearing lugs of the aft face of the center section of 
the horizontal stabilizer; measuring crack length and blending out 
cracks; and replacing the horizontal stabilizer center section rib, if 
necessary. The SNPRM proposed to specify the corrective actions for 
airplanes on which cracking is found during the inspections of the 
blendout required by paragraphs (h)(1) and (j)(1) of the SNPRM.

Comments

    We gave the public the opportunity to participate in developing 
this AD. The following presents the comments received on the proposal 
(77 FR 55773, September 11, 2012) and the FAA's response to each 
comment. One representative of Boeing concurred with the contents of 
the proposed rule.

Request To Revise Paragraphs (h)(1)(ii) and (j)(1)(ii) of SNPRM (77 FR 
55773, September 11, 2012)

    Another representative of Boeing requested that we revise 
paragraphs (h)(1)(ii) and (j)(1)(ii) of the SNPRM (77 FR 55773, 
September 11, 2012). Those paragraphs specify that if any cracking is 
found during any inspection of the blendout to do a replacement. The 
commenter requested that we specify either doing a repair or a 
replacement.
    We disagree with the request To revise paragraphs (h)(1)(ii) and 
(j)(1)(ii) of this AD to allow a repair as an option to the 
replacement. Providing a repair option would allow a blendout repair 
for cracking found in a rib with a blendout repair already 
accomplished. The intent of the AD is to allow only one blendout repair 
before the rib must be replaced. No change has been made to the AD in 
this regard.

Request To Permit Rib Replacement Using Structural Repair Manual

    American Airlines (American) stated that paragraphs (h)(2) and 
(j)(2) of the SNPRM (77 FR 55773, September 11, 2012) would require 
replacing the horizontal stabilizer rib in accordance with a method 
approved by the FAA. American stated that the rib replacement is not a 
type design change, and this action should be allowed to be 
accomplished with approved type design data and the structural repair 
manual (SRM) without the need for FAA approval.
    We partially agree. Although we have determined that rib 
replacement using the SRM is acceptable, we cannot refer to the SRM 
without revision levels and dates as a method of compliance because 
doing so violates Office of the Federal Register regulations for 
approving materials that are incorporated by reference. We will 
consider approving a global AMOC allowing rib replacement using the 
SRM.

Conclusion

    We reviewed the relevant data, considered the comments received, 
and determined that air safety and the public interest require adopting 
the AD as proposed--except for minor editorial changes. We have 
determined that these minor changes:
     Are consistent with the intent that was proposed in the 
SNPRM (77 FR 55773, September 11, 2012) for correcting the unsafe 
condition; and
     Do not add any additional burden upon the public than was 
already proposed in the SNPRM (77 FR 55773, September 11, 2012).

Interim Action

    We consider this AD interim action since investigation is ongoing 
and no terminating action has been developed yet. The manufacturer is 
currently developing a modification that will address the unsafe 
condition identified in this AD. Once this modification is developed, 
approved, and available, we may consider additional rulemaking.

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Costs of Compliance

    We estimate that this AD affects 668 airplanes of U.S. registry.
    We estimate the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                    Cost per       Cost on U.S.
             Action                        Labor cost             Parts cost        product         operators
----------------------------------------------------------------------------------------------------------------
Inspection......................  6 work-hours x $85 per hour              $0             $510         $340,680
                                   = $510 per inspection
                                   cycle.
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that would enable us to provide 
labor cost estimates for the on-condition actions (blendout repair(s) 
or replacement of center section rib(s)) specified in this AD. However, 
we have been advised that replacement parts would be $14,500 per 
horizontal stabilizer rib crack repair kit.

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

    This AD will not have federalism implications under Executive Order 
13132. This AD will 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 this AD:
    (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),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) 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.

List of Subjects in 14 CFR Part 39

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

Adoption of the Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive (AD):

2013-05-02 The Boeing Company: Amendment 39-17374; Docket No. FAA-
2011-0909; Directorate Identifier 2011-NM-027-AD.

(a) Effective Date

    This AD is effective April 15, 2013.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company 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, as identified in Boeing Alert Service 
Bulletin MD80-55A069, dated January 19, 2011.

(d) Subject

    Air Transport Association (ATA) of America Code 55, Stabilizers.

(e) Unsafe Condition

    This AD was prompted by reports of cracks of the hinge bearing 
lugs of the center section ribs of the horizontal stabilizer. We are 
issuing this AD to detect and correct cracking in the hinge bearing 
lugs of the horizontal stabilizer center section ribs, which could 
result in failure of the lugs, resulting in the inability of the 
horizontal stabilizer to sustain the required limit loads and 
consequent loss of control of the airplane.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Inspection of Horizontal Stabilizer Ribs Made From 7075-T7351 
Material

    For Group 1 airplanes, as identified in Boeing Alert Service 
Bulletin MD80-55A069, dated January 19, 2011: Before the 
accumulation of 23,000 total flight cycles, or within 4,383 flight 
cycles after the effective date of this AD, whichever occurs later, 
do a high frequency eddy current (HFEC) inspection for cracking of 
the left and right rib hinge bearing lugs of the aft face of the 
center section of the horizontal stabilizer, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin MD80-
55A069, dated January 19, 2011. For any crack-free lug, repeat the 
inspection thereafter at intervals not to exceed 8,200 flight 
cycles.

(h) Repair and Replacement for Cracking of 7075-T7351 Material

    If, during any inspection required by paragraph (g) of this AD, 
any crack is found: Before further flight, measure the length of the 
crack between the points specified in Boeing Alert Service Bulletin 
MD80-55A069, dated January 19, 2011. Do the action in accordance 
with the Accomplishment Instructions of Boeing Alert Service 
Bulletin MD80-55A069, dated January 19, 2011.
    (1) If the crack length between points `A' and `B' is less than 
or equal to 0.15 inch and the crack length between points `C' and 
`D' is less than or equal to 0.05 inch: Before further flight, blend 
out the crack, in accordance with the Accomplishment Instructions of 
Boeing Alert Service Bulletin MD80-55A069, dated January 19, 2011. 
Within 15,600 flight cycles after doing the blendout, do an HFEC 
inspection of the blendout on the center section rib hinge bearing 
lug for cracking, in accordance with the Accomplishment Instructions 
of Boeing Alert Service Bulletin MD80-55A069, dated January 19, 
2011.
    (i) If no cracking is found, repeat the inspection thereafter at 
intervals not to exceed 3,900 flight cycles.
    (ii) If cracking is found during any inspection of the blendout, 
before further flight, do the replacement required by paragraph 
(h)(2) of this AD, and do the inspections required by paragraph 
(h)(2) of this AD at the times specified in paragraph (h)(2) of this 
AD.
    (2) If the crack length between points `A' and `B' is greater 
than 0.15 inch or the crack length between points `C' and `D' is 
greater

[[Page 15283]]

than 0.05 inch: Before further flight, replace the horizontal 
stabilizer center section rib with a new horizontal stabilizer 
center section rib, using a method approved in accordance with the 
procedures specified in paragraph (l) of this AD. Repeat the 
inspection required by paragraph (g) of this AD one time before the 
accumulation of 23,000 total flight cycles on the new horizontal 
stabilizer center section rib, and thereafter at intervals not to 
exceed 11,300 flight cycles.

(i) Inspection of Horizontal Stabilizer Ribs Made From 7050-T7451 
Material

    For Group 2 airplanes, as identified in Boeing Alert Service 
Bulletin MD80-55A069, dated January 19, 2011: Before the 
accumulation of 23,000 total flight cycles, or within 4,383 flight 
cycles after the effective date of this AD, whichever occurs later, 
do an HFEC inspection for cracking of the left and right rib hinge 
bearing lugs of the aft face of the center section of the horizontal 
stabilizer, in accordance with the Accomplishment Instructions of 
Boeing Alert Service Bulletin MD80-55A069, dated January 19, 2011. 
For any crack-free lug, repeat the inspection thereafter at 
intervals not to exceed 11,300 flight cycles.

(j) Repair and Replacement for Cracking of 7050-T7451 Material

    If, during any inspection required by paragraph (i) of this AD, 
any crack is found: Before further flight, measure the length of the 
crack between the points specified in, and in accordance, with the 
Accomplishment Instructions of Boeing Alert Service Bulletin MD80-
55A069, dated January 19, 2011.
    (1) If the crack length between points `A' and `B' is less than 
or equal to 0.15 inch and the crack length between points `C' and 
`D' is less than or equal to 0.05 inch: Before further flight, 
blendout the crack, in accordance with the Accomplishment 
Instructions of Boeing Alert Service Bulletin MD80-55A069, dated 
January 19, 2011. Within 15,600 flight cycles after doing the 
blendout, do an HFEC inspection of the blendout on the center 
section rib hinge bearing lug for cracking, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin MD80-
55A069, dated January 19, 2011.
    (i) If no cracking is found, repeat the inspection thereafter at 
intervals not to exceed 5,800 flight cycles.
    (ii) If cracking is found during any inspection of the blendout, 
before further flight, do the replacement required by paragraph 
(j)(2) of this AD, and do the inspections required by paragraph 
(j)(2) of this AD at the times specified in paragraph (j)(2) of this 
AD.
    (2) If the crack length between points `A' and `B' is greater 
than 0.15 inch or the crack length between points `C' and `D' is 
greater than 0.05 inch: Before further flight, replace the 
horizontal stabilizer center section rib with a new horizontal 
stabilizer center section rib, using a method approved in accordance 
with the procedures specified in paragraph (l) of this AD. Repeat 
the inspection required by paragraph (i) of this AD one time before 
the accumulation of 23,000 total flight cycles on the new horizontal 
stabilizer center section rib, and thereafter at intervals not to 
exceed 11,300 flight cycles.

(k) No Reporting Requirement

    Although Boeing Alert Service Bulletin MD80-55A069, dated 
January 19, 2011, specifies to submit certain information to the 
manufacturer, this AD does not include that requirement.

(l) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Los Angeles Aircraft Certification Office 
(ACO), FAA, has the authority to approve AMOCs for this AD, if 
requested using the procedures found in 14 CFR 39.19. In accordance 
with 14 CFR 39.19, send your request to your principal inspector or 
local Flight Standards District Office, as appropriate. If sending 
information directly to the manager of the ACO, send it to the 
attention of the person identified in the Related Information 
section of this AD.
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.
    (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 the 
Boeing Commercial Airplanes Organization Designation Authorization 
(ODA) that has been authorized by the Manager, Los Angeles ACO, to 
make those findings. For a repair 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.

(m) Related Information

    For more information about this AD, contact Roger Durbin, 
Aerospace Engineer, Airframe Branch, ANM-120L, FAA, Los Angeles 
Aircraft Certification Office (ACO), 3960 Paramount Boulevard, 
Lakewood, CA 90712-4137; phone: 562-627-5233; fax: 562-627-5210; 
email: roger.durbin@faa.gov.

(n) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the service information listed 
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) Boeing Alert Service Bulletin MD80-55A069, dated January 19, 
2011.
    (ii) Reserved.
    (3) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Data & Services Management, 
3855 Lakewood Boulevard, MC D800-0019, Long Beach, California 90846-
0001; telephone 206-544-5000, extension 2; fax 206-766-5683; 
Internet https://www.myboeingfleet.com.
    (4) You may view this service information at FAA, Transport 
Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For 
information on the availability of this material at the FAA, call 
425-227-1221.
    (5) You may view this service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Renton, Washington, on February 22, 2013.
Jeffrey E. Duven,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2013-05196 Filed 3-8-13; 8:45 am]
BILLING CODE 4910-13-P


