[Federal Register Volume 82, Number 98 (Tuesday, May 23, 2017)]
[Rules and Regulations]
[Pages 23504-23507]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-10252]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2016-9433; Directorate Identifier 2016-NM-159-AD; 
Amendment 39-18901; AD 2017-11-02]
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 MD-90-30 airplanes. This AD was prompted by a 
report of cracking in a horizontal stabilizer rear spar cap. This AD 
requires repetitive inspections for any crack in the left and right 
side horizontal stabilizer rear spar upper caps, and repair or 
replacement if necessary. We are issuing this AD to address the unsafe 
condition on these products.

DATES: This AD is effective June 27, 2017.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of June 27, 
2017.

ADDRESSES: For service information identified in this final rule, 
contact Boeing Commercial Airplanes, Attention: Contractual & Data 
Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 
90740-5600; telephone 562-797-1717; Internet https://www.myboeingfleet.com. You may view this referenced service information 
at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., 
Renton, WA. For information on the availability of this material at the 
FAA, call 425-227-1221. It is also available on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2016-
9433.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2016-
9433; 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 Docket 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: James Guo, Aerospace Engineer, 
Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification 
Office (ACO), 3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: 
562-627-5357; fax: 562-627-5210; email: [email protected].

SUPPLEMENTARY INFORMATION: 

[[Page 23505]]

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 by adding an AD that would apply to all The Boeing Company 
Model MD-90-30 airplanes. The NPRM published in the Federal Register on 
December 5, 2016 (81 FR 87499). The NPRM was prompted by a report of 
cracking in an MD-90 horizontal stabilizer rear spar cap at station XE 
 5.931. The NPRM proposed to require repetitive open hole 
eddy current high frequency (ETHF) or surface eddy current low 
frequency (ETLF) inspections for any crack in the left and right side 
horizontal stabilizer rear spar upper caps, and repair or replacement 
if necessary. We are issuing this AD to detect and correct fatigue 
cracking of the horizontal stabilizer rear spar upper cap, which could 
adversely affect the structural integrity of the airplane.

Comments

    We gave the public the opportunity to participate in developing 
this AD. The following presents the comments received on the NPRM and 
the FAA's response to each comment.

Support for the NPRM

    Boeing stated that it supports the NPRM.

Request To Allow Installation of a Serviceable Spare as a Corrective 
Action

    Delta Airlines requested that we allow installation of a qualified 
serviceable spare horizontal stabilizer as a corrective action in lieu 
of repairing or replacing the horizontal stabilizer. Delta noted that 
this type of corrective action has been approved as an alternative 
method of compliance (AMOC) for other ADs affecting the horizontal 
stabilizer.
    We disagree with the request. While an AMOC has been previously 
granted to allow applicants to replace an unserviceable stabilizer with 
a serviceable stabilizer, each such AMOC approval required the 
applicant to demonstrate that they had a sufficient program in place to 
trace, document, inspect, and install the serviceable horizontal 
stabilizers. The details of such a program cannot be prescribed and 
documented within an AD. However, we will consider requests for 
approval of an AMOC under the provisions of paragraph (j) of this AD.

Explanation of Change to NPRM

    We revised paragraph (g) of the proposed AD to refer to the 
compliance times of both table 1 and table 2 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin MD90-55A018, dated 
June 29, 2016. The reference to table 2 had been inadvertently omitted 
from the proposed AD. Table 2 specifies the same compliance times as 
table 1, but table 2 applies to the right side horizontal rear spar 
upper cap, while table 1 applies to the left side.

Conclusion

    We reviewed the relevant data, considered the comments received, 
and determined that air safety and the public interest require adopting 
this AD with the change described previously, and minor editorial 
changes. We have determined that these minor changes:
     Are consistent with the intent that was proposed in the 
NPRM for correcting the unsafe condition; and
     Do not add any additional burden upon the public than was 
already proposed in the NPRM.
    We also determined that these changes will not increase the 
economic burden on any operator or increase the scope of this AD.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Alert Service Bulletin MD90-55A018, dated June 
29, 2016. The service information describes procedures for repetitive 
open hole ETHF or surface ETLF inspections for any crack in the left 
and right side horizontal stabilizer rear spar upper caps common to the 
elevator hinge fitting at station XE =  5.931, and repair 
or replacement. This service information is reasonably available 
because the interested parties have access to it through their normal 
course of business or by the means identified in the ADDRESSES section.

Costs of Compliance

    We estimate that this AD affects 105 airplanes of U.S. registry. We 
estimate the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                 Cost on U.S.
             Action                     Labor cost          Parts cost     Cost per product        operators
----------------------------------------------------------------------------------------------------------------
Inspection.....................  8 work-hours x $85 per               $0  $680 per            $71,400 per
                                  hour = $680 per                          inspection cycle.   inspection cycle.
                                  inspection cycle.
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to do any necessary repairs or 
replacements that would be required based on the results of the 
inspection. We have no way of determining the number of aircraft that 
might need these actions:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                    Action                                 Labor cost               Parts cost        product
----------------------------------------------------------------------------------------------------------------
Upper cap splice repair or replacement (each    368 work-hours x $85 per hour =          $64,306         $95,586
 side).                                          $31,280.
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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

[[Page 23506]]

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):

2017-11-02 The Boeing Company: Amendment 39-18901; Docket No. FAA-
2016-9433; Directorate Identifier 2016-NM-159-AD.

(a) Effective Date

    This AD is effective June 27, 2017.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all The Boeing Company Model MD-90-30 
airplanes, certificated in any category.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by a report of cracking in a horizontal 
stabilizer rear spar cap at station XE =  5.931. We are 
issuing this AD to detect and correct fatigue cracking of the 
horizontal stabilizer rear spar upper cap, which could adversely 
affect the structural integrity of the airplane.

(f) Compliance

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

(g) Repetitive Open Hole Eddy Current High Frequency or Surface Eddy 
Current Low Frequency Inspections

    Except as required by paragraph (i) of this AD, at the 
applicable times specified in table 1 or table 2 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin MD90-55A018, dated 
June 29, 2016: Do either an open hole eddy current high frequency 
(ETHF) or a surface eddy current low frequency (ETLF) inspection for 
any crack in the left and right side horizontal stabilizer rear spar 
upper caps common to the elevator hinge fitting at station XE = 
 5.931, in accordance with the Accomplishment 
Instructions of Boeing Alert Service Bulletin MD90-55A018, dated 
June 29, 2016. Repeat the inspection thereafter at the time 
specified in tables 1 through 4, as applicable, of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin MD90-55A018, dated 
June 29, 2016.

(h) Horizontal Rear Spar Upper Cap Splice Repair or Replacement

    If any crack is found during any inspection required by 
paragraph (g) of this AD, repair or replace before further flight in 
accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin MD90-55A018, dated June 29, 2016.

(i) Service Information Exception

    Where Boeing Alert Service Bulletin MD90-55A018, dated June 29, 
2016, specifies a compliance time ``after the original issue date of 
this service bulletin,'' this AD requires compliance within the 
specified compliance time after the effective date of this AD.

(j) 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 paragraph (k) of this AD. 
Information may be emailed to: [email protected].
    (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, modification, or alteration 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. To be approved, 
the repair method, modification deviation, or alteration deviation 
must meet the certification basis of the airplane, and the approval 
must specifically refer to this AD.
    (4) For service information that contains steps that are labeled 
as Required for Compliance (RC), the provisions of paragraphs 
(j)(4)(i) and (j)(4)(ii) of this AD apply.
    (i) The steps labeled as RC, including substeps under an RC step 
and any figures identified in an RC step, must be done to comply 
with the AD. If a step or substep is labeled ``RC Exempt,'' then the 
RC requirement is removed from that step or substep. An AMOC is 
required for any deviations to RC steps, including substeps and 
identified figures.
    (ii) Steps not labeled as RC may be deviated from using accepted 
methods in accordance with the operator's maintenance or inspection 
program without obtaining approval of an AMOC, provided the RC 
steps, including substeps and identified figures, can still be done 
as specified, and the airplane can be put back in an airworthy 
condition.

(k) Related Information

    For more information about this AD, contact James Guo, Aerospace 
Engineer, Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft 
Certification Office (ACO), 3960 Paramount Boulevard, Lakewood, CA 
90712-4137; phone: 562-627-5357; fax: 562-627-5210; email: 
[email protected].

(l) 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 MD90-55A018, dated June 29, 
2016.
    (ii) Reserved.
    (3) For Boeing service information identified in this AD, 
contact Boeing Commercial Airplanes, Attention: Contractual & Data 
Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 
90740-5600; telephone 562-797-1717; Internet https://www.myboeingfleet.com. You may view this referenced service 
information at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue SW., Renton, WA.
    (4) You may view this service information at the FAA, Transport 
Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. 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://

[[Page 23507]]

www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Renton, Washington, on May 12, 2017.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2017-10252 Filed 5-22-17; 8:45 am]
BILLING CODE 4910-13-P