AD 2014-08-11
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 737-600 Series | Airworthiness Directives; the Boeing Company Airplanes |
| aircraft | The Boeing Company | 737-700 Series | Airworthiness Directives; the Boeing Company Airplanes |
| aircraft | The Boeing Company | 737-700C Series | Airworthiness Directives; the Boeing Company Airplanes |
| aircraft | The Boeing Company | 737-800 Series | Airworthiness Directives; the Boeing Company Airplanes |
| aircraft | The Boeing Company | 737-900 Series | Airworthiness Directives; the Boeing Company Airplanes |
Unsafe Condition
Stress corrosion cracking of the forward trunnion pins, which could result in fracture of the pins and consequent collapse of the main landing gear (MLG).
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect the transition radius of the MLG forward trunnion pins for discrepancies, including finish damage, corrosion, pitting, and base metal scratches. Perform repetitive lubrications of the right and left MLG forward trunnion pins. Take corrective actions if necessary, including replacing or overhauling the trunnion pins to terminate the required actions.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 50 flight hours after the effective date of this AD.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
The Boeing Company Model 737-600, -700, -700C, and -800 series airplanes, including additional airplanes added to the applicability of AD 2009-24-07.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
We are superseding Airworthiness Directive (AD) 2009-24-07 for certain the Boeing Company Model 737-600, -700, -700C, and -800 series airplanes. AD 2009-24-07 required repetitive lubrications of the right and left main landing gear (MLG) forward trunnion pins. AD 2009-24-07 also required an inspection for discrepancies of the transition radius of the MLG forward trunnion pins, and corrective actions if necessary. For certain airplanes, AD 2009-24-07 required repetitive detailed inspections for discrepancies (including finish damage, corrosion, pitting, and base metal scratches) of the transition radius of the left and right MLG trunnion pins, and corrective action if necessary. Replacing or overhauling the trunnion pins terminates the actions required by AD 2009-24-07. This new AD adds airplanes to the applicability of AD 2009-24-07. This AD was prompted by reports of corrosion protection damage to the forward trunnion pin on additional airplanes. We are issuing this AD to prevent stress corrosion cracking of the forward trunnion pins, which could result in fracture of the pins and consequent collapse of the MLG.
Applicability Source Text
Show captured applicability text from the source AD
(c) Applicability
(1) This AD applies to The Boeing Company Model 737-600, -700, -
700C, -800 and -900 series airplanes, certificated in any category;
as identified in Boeing Special Attention Service Bulletin 737-32-
1402, Revision 1, dated February 7, 2013.
(2) Installation of Supplemental Type Certificate (STC)
ST00830SE (<a href="http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/408E012E008616A7862578880060456C?OpenDocument&Highlight">http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/408E012E008616A7862578880060456C?OpenDocument&Highlight</a>=st00830se)
does not affect the ability to accomplish the actions required by
this AD. Therefore, for airplanes on which STC ST00830SE is
installed, a ``change in product'' alternative method of compliance
(AMOC) approval request is not necessary to comply with the
requirements of 14 CFR 39.17.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 79, Number 82 (Tuesday, April 29, 2014)]
[Rules and Regulations]
[Pages 23903-23906]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2014-09309]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2013-0690; Directorate Identifier 2013-NM-088-AD;
Amendment 39-17835; AD 2014-08-11]
RIN 2120-AA64
Airworthiness Directives; the Boeing Company Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: We are superseding Airworthiness Directive (AD) 2009-24-07 for
certain the Boeing Company Model 737-600, -700, -700C, and -800 series
airplanes. AD 2009-24-07 required repetitive lubrications of the right
and left main landing gear (MLG) forward trunnion pins. AD 2009-24-07
also required an inspection for discrepancies of the transition radius
of the MLG forward trunnion pins, and corrective actions if necessary.
For certain airplanes, AD 2009-24-07 required repetitive detailed
inspections for discrepancies (including finish damage, corrosion,
pitting, and base metal scratches) of the transition radius of the left
and right MLG trunnion pins, and corrective action if necessary.
Replacing or overhauling the trunnion pins terminates the actions
required by AD 2009-24-07. This new AD adds airplanes to the
applicability of AD 2009-24-07. This AD was prompted by reports of
corrosion protection damage to the forward trunnion pin on additional
airplanes. We are issuing this AD to prevent stress corrosion cracking
of the forward trunnion pins, which could result in fracture of the
pins and consequent collapse of the MLG.
DATES: This AD is effective June 3, 2014.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of June 3,
2014.
ADDRESSES: For service information identified in this AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management,
P.O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; telephone 206-544-
5000, extension 1; fax 206-766-5680; 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.
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-2013-
0690; 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: Nancy Marsh, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6440; fax:
425-917-6590; email: <a href="/cdn-cgi/l/email-protection#cfa1aea1acb6e1a2aebdbca78fa9aeaee1a8a0b9"><span class="__cf_email__" data-cfemail="b0ded1ded3c99eddd1c2c3d8f0d6d1d19ed7dfc6">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 to supersede AD 2009-24-07, Amendment 39-16095 (74 FR 62231,
November 27, 2009). AD 2009-24-07 applied to certain The Boeing Company
Model 737-600, -700, -700C, and -800 series airplanes. The NPRM
published in the Federal Register on August 13, 2013 (78 FR 49229). The
NPRM was prompted by reports of corrosion protection damage to the
forward trunnion pin on additional airplanes. The NPRM proposed to
continue to require repetitive lubrications of the right and left main
landing gear (MLG) forward trunnion pins. The NPRM also proposed to
continue to require an inspection for discrepancies of the transition
radius of the MLG forward trunnion pins, and corrective actions if
necessary. For certain airplanes, the NPRM proposed to continue to
require repetitive detailed inspections for discrepancies (including
finish damage, corrosion, pitting, and base metal scratches) of the
transition radius of the left and right MLG trunnion pins, and
corrective action if necessary. Replacing or overhauling the trunnion
pins would terminate the actions required by AD 2009-24-07. The NPRM
proposed to add airplanes to the applicability of AD 2009-24-07. We are
issuing this AD to prevent stress corrosion cracking of the forward
trunnion pins, which could result in fracture of the pins and
consequent collapse of the MLG.
Comments
We gave the public the opportunity to participate in developing
this AD. The following presents the comments received on the proposal
(78 FR 49229, August 13, 2013) and the FAA's response to each comment.
Concurrence With the NPRM (78 FR 49229, August 13, 2013)
Boeing stated that it concurs with the content of the NPRM (78 FR
49229, August 13, 2013).
Supplemental Type Certificate (STC) Winglet Comment
Aviation Partners Boeing stated that the installation of winglets
per STC ST00830SE (<a href="http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/408E012E008616A7862578880060456C?OpenDocument&Highlight">http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/408E012E008616A7862578880060456C?OpenDocument&Highlight</a>=st00830se) does
not affect the accomplishment of the manufacturer's service
instructions.
We have redesignated paragraph (c) of the NPRM (78 FR 49229, August
13, 2013) as paragraph (c)(1) of this AD, and added paragraph (c)(2) to
this AD to state that installation of STC ST00830SE (<a href="http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/408E012E008616A7862578880060456C?OpenDocument&Highlight">http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/408E012E008616A7862578880060456C?OpenDocument&Highlight</a>=st00830se) does
not affect the ability to accomplish the actions required by this AD.
Therefore, for airplanes on which STC ST00830SE is installed, a
``change in product'' alternative method of compliance (AMOC) approval
request is not necessary to comply with the requirements of 14 CFR
39.17. For all other AMOC requests, the operator must request approval
of an AMOC in accordance with the procedures specified in paragraph (l)
of this AD.
Request for Clarification of Location of Trunnion Pins
Delta asked for clarification of the term ``trunnion pins'' as
specified in the
[[Page 23904]]
NPRM (78 FR 49229, August 13, 2013). Delta stated that throughout the
preamble of the NPRM, the subject pins are referred to as ``forward
trunnion pins;'' however, in paragraphs (h) and (i) of the NPRM, the
location is omitted and the term ``trunnion pins'' is used. Delta noted
that since forward and aft trunnion pins are installed, failing to
identify the affected pin as a ``forward trunnion pin'' adds a
potential for errors.
We agree that the term ``trunnion pins'' should be clarified to
include the pin location. We have changed paragraphs (h) and (i) of
this final rule to specify ``forward trunnion pins.''
Request To Use Alternate Grease for Lubrication of the Forward Trunnion
Pins
Delta asked that paragraph (g) of the NPRM (78 FR 49229, August 13,
2013) be changed to allow the use of Royco-11MS grease as an alternate
to the BMS 3-33 grease specified in Boeing Special Attention Service
Bulletin 737-32-1402, Revision 1, dated February 7, 2013. Delta stated
that Royco-11MS is the standard grease used on Delta aircraft landing
gear applications, and it would like to continue using this grease when
lubricating the forward trunnion pins.
We do not agree to allow the use of an alternative type of grease.
Approval of an operator's unique maintenance actions is dependent on
its ability to provide acceptable data supporting the request. We would
not provide such an approval to all operators via a change to the NPRM
(78 FR 49229, August 13, 2013). However, we would consider this request
for approval of unique maintenance practices in accordance with the
procedures identified in paragraph (l) of this AD. We have made no
change to this final rule in this regard.
Request To Further Clarify Certain Language
Ryanair (RYR) asked that clarification be provided to reflect new
information it received from Boeing. RYR stated that the intent of
paragraphs (g) and (h) of the NPRM (78 FR 49229, August 13, 2013)
appears to be to require that the 30-day repetitive lubrication task
continue until all repetitive inspections are completed, as stated in
Notes (a) and (b) of paragraph 1.E., ``Compliance,'' of Boeing Special
Attention Service Bulletin 737-32-1402, Revision 1, dated February 7,
2013. RYR received correspondence from Boeing stating that the 30-day
lubrication task is terminated after accomplishing the first in-situ
detailed inspection. RYR recommends the information from Boeing be
included in the NPRM.
RYR has correctly interpreted the requirements in paragraphs (g)
and (h) of this AD. However, we find that further clarification is
necessary. If certain discrepancies are found during the detailed
inspection of the forward trunnion pins, replacing the affected
trunnion pins terminates the repetitive requirements in this AD. If no
discrepancies are found during the detailed inspection of the forward
trunnion pins, an additional lubrication of the left and right MLG
forward trunnion is required, which terminates the repetitive
requirements in this AD. If certain other discrepancies are found
during the detailed inspection of the forward trunnion pins, the
lubrications and detailed inspections must be repeated until overhaul
or replacement of the affected trunnion pins.
Additionally, Boeing did not provide any new information or data to
the FAA, nor are we aware of any intention to revise its service
information. However, under the provisions of paragraph (l) of this AD,
we may consider requests for approval of an alternative method of
compliance (AMOC) if sufficient data are submitted to substantiate that
terminating the repetitive lubrications after doing the first detailed
inspection would provide an acceptable level of safety. In light of
these factors, we have made no change to this final rule.
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 changes described previously. We also determined that
these changes will not increase the economic burden on any operator or
increase the scope of this AD.
Costs of Compliance
We estimate that this AD affects 431 airplanes of U.S. registry.
Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
Number of U.S.-
Action Work hours Average labor Parts Cost per product registered Fleet cost
rate per hour airplanes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Repetitive lubrications.............. 1 $85 $0 $85 per lubrication..... 431 $36,635 per
lubrication.
Repetitive inspections............... 8 85 0 $680 per inspection 431 $293,080 per inspection
cycle. cycle.
--------------------------------------------------------------------------------------------------------------------------------------------------------
We have received no definitive data that would enable us to provide
cost estimates for the on-condition actions specified in this AD.
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 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,
[[Page 23905]]
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 removing Airworthiness Directive (AD)
2009-24-07, Amendment 39-16095 (74 FR 62231, November 27, 2009), and
adding the following new AD:
2014-08-11 Boeing: Amendment 39-17835; Docket No. FAA-2013-0690;
Directorate Identifier 2013-NM-088-AD.
(a) Effective Date
This AD is effective June 3, 2014.
(b) Affected ADs
This AD supersedes AD 2009-24-07, Amendment 39-16095 (74 FR
62231, November 27, 2009).
(c) Applicability
(1) This AD applies to The Boeing Company Model 737-600, -700, -
700C, -800 and -900 series airplanes, certificated in any category;
as identified in Boeing Special Attention Service Bulletin 737-32-
1402, Revision 1, dated February 7, 2013.
(2) Installation of Supplemental Type Certificate (STC)
ST00830SE (<a href="http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/408E012E008616A7862578880060456C?OpenDocument&Highlight">http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/408E012E008616A7862578880060456C?OpenDocument&Highlight</a>=st00830se)
does not affect the ability to accomplish the actions required by
this AD. Therefore, for airplanes on which STC ST00830SE is
installed, a ``change in product'' alternative method of compliance
(AMOC) approval request is not necessary to comply with the
requirements of 14 CFR 39.17.
(d) Subject
Air Transport Association (ATA) of America Code 32, Landing
gear.
(e) Unsafe Condition
This AD was prompted by a report that the protective finishes on
the forward trunnion pins for the left and right MLG might have been
damaged during final assembly. We are issuing this AD to prevent
stress corrosion cracking of the forward trunnion pins, which could
result in fracture of the pins and consequent collapse of the MLG.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Repetitive Lubrications
At the applicable compliance time specified in paragraph 1.E.,
``Compliance,'' of Boeing Special Attention Service Bulletin 737-32-
1402, Revision 1, dated February 7, 2013, except as required by
paragraph (j) of this AD: Lubricate the left and right MLG forward
trunnion pins, in accordance with the Accomplishment Instructions of
Boeing Special Attention Service Bulletin 737-32-1402, Revision 1,
dated February 7, 2013. Repeat the lubrication thereafter at the
applicable time specified in paragraph 1.E., ``Compliance,'' until
all applicable requirements of paragraph (h) of this AD have been
accomplished.
(h) Inspection
At the applicable compliance time specified in paragraph 1.E.,
``Compliance,'' of Boeing Special Attention Service Bulletin 737-32-
1402, Revision 1, dated February 7, 2013, except as required by
paragraph (j) of this AD: Except as provided by paragraph (i) of
this AD, do a detailed inspection for discrepancies (including
finish damage, corrosion, pitting, and base metal scratches) of the
transition radius of the left and right MLG forward trunnion pins,
and do all applicable repetitive inspections and related
investigative and corrective actions, in accordance with the
Accomplishment Instructions of Boeing Special Attention Service
Bulletin 737-32-1402, Revision 1, dated February 7, 2013.
Accomplishing the detailed inspections (initial and repetitive) and
all applicable corrective actions specified in this paragraph
terminates the repetitive lubrication requirements of paragraph (g)
of this AD.
(i) Optional Terminating Action
Overhauling or replacing a forward trunnion pin, in accordance
with the Accomplishment Instructions of Boeing Special Attention
Service Bulletin 737-32-1402, Revision 1, dated February 7, 2013,
ends the repetitive lubrication requirements of paragraph (g) of
this AD, and the actions required by paragraph (h) of this AD, for
that forward trunnion pin only.
(j) Exception to Service Information Specifications
Where Boeing Special Attention Service Bulletin 737-32-1402,
Revision 1, dated February 7, 2013, specifies a compliance time
``from the date of Revision 1 of this service bulletin,'' this AD
requires compliance within the specified compliance time after the
effective date of this AD.
(k) Credit for Previous Actions
This paragraph provides credit for the actions required by this
AD, if those actions were performed before the effective date of
this AD using Boeing Special Attention Service Bulletin 737-32-1402,
dated August 6, 2008, which was incorporated by reference in AD
2009-24-07, Amendment 39-16095 (74 FR 62231, November 27, 2009).
(l) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Seattle 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
(m)(1) of this AD. Information may be emailed to: <a href="/cdn-cgi/l/email-protection#8cb5a1cdc2c1a1dfe9edf8f8e0e9a1cdcfc3a1cdc1c3cfa1dee9fdf9e9fff8ffcceaededa2ebe3fa"><span class="__cf_email__" data-cfemail="fec7d3bfb0b3d3ad9b9f8a8a929bd3bfbdb1d3bfb3b1bdd3ac9b8f8b9b8d8a8dbe989f9fd0999188">[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 required by this AD if it is approved by the
Boeing Commercial Airplanes ODA that has been authorized by the
Manager, Seattle ACO, to make those findings. For a repair method to
be approved, the repair must meet the certification basis of the
airplane, and the approval must specifically refer to this AD.
(4) AMOCs approved previously for AD 2009-24-07, Amendment 39-
16095 (74 FR 62231, November 27, 2009), are approved as AMOCs for
the corresponding provisions of paragraphs (g) and (h) of this AD.
(m) Related Information
(1) For more information about this AD, contact Nancy Marsh,
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft
Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356;
phone: 425-917-6440; fax: 425-917-6590; email: <a href="/cdn-cgi/l/email-protection#3b555a55584215565a4948537b5d5a5a155c544d"><span class="__cf_email__" data-cfemail="284649464b510645495a5b40684e4949064f475e">[email protected]</span></a>.
(2) Service information identified in this AD that is not
incorporated by reference in this AD may be obtained at the
addresses specified in paragraphs (n)(3) and (n)(4) of this AD.
(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 Special Attention Service Bulletin 737-32-1402,
Revision 1, dated February 7, 2013.
(ii) Reserved.
(3) For service information identified in this AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management,
P.O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; telephone 206-544-
5000, extension 1; fax 206-766-5680; Internet <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>.
(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
[[Page 23906]]
Administration (NARA). For information on the availability of this
material at NARA, call 202-741-6030, or go to: <a href="http://www.archives.gov/federal-register/cfr/ibr-locations.html">http://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.
Issued in Renton, Washington, on April 14, 2014.
Jeffrey E. Duven,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2014-09309 Filed 4-28-14; 8:45 am]
BILLING CODE 4910-13-P
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