AD 2017-11-02
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | MD-90-30 | Airworthiness Directives; The Boeing Company Airplanes |
Unsafe Condition
Cracking in the horizontal stabilizer rear spar upper caps, specifically at station XE ± 5.931, which could affect structural integrity.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Conduct 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. Repair or replace the spar caps if cracks are found.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the compliance times specified in Boeing Alert Service Bulletin MD90-55A018, Table 1 for the left side and Table 2 for the right side.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
The Boeing Company Model MD-90-30 airplanes, certificated in any category.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
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.
Applicability Source Text
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(c) Applicability
This AD applies to all The Boeing Company Model MD-90-30
airplanes, certificated in any category.
Document Text
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[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 [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[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 <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>. 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 <a href="http://www.regulations.gov">http://www.regulations.gov</a> by searching for and locating Docket No. FAA-2016-
9433.
Examining the AD Docket
You may examine the AD docket on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a> 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: <a href="/cdn-cgi/l/email-protection#cba1aaa6aeb8e5acbea48badaaaae5aca4bd"><span class="__cf_email__" data-cfemail="442e252921376a23312b042225256a232b32">[email protected]</span></a>.
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
<plus-minus> 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:
<bullet> Are consistent with the intent that was proposed in the
NPRM for correcting the unsafe condition; and
<bullet> 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 = <plus-minus> 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.
----------------------------------------------------------------------------------------------------------------
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 = <plus-minus> 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 =
<plus-minus> 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: <a href="/cdn-cgi/l/email-protection#477e6a06090a6a0b060604086a060a08046a15223632223433340721262669202831"><span class="__cf_email__" data-cfemail="c2fbef838c8fef8e8383818def838f8d81ef90a7b3b7a7b1b6b182a4a3a3eca5adb4">[email protected]</span></a>.
(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:
<a href="/cdn-cgi/l/email-protection#3359525e56401d54465c735552521d545c45"><span class="__cf_email__" data-cfemail="8ee4efe3ebfda0e9fbe1cee8efefa0e9e1f8">[email protected]</span></a>.
(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 <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>. 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
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