AD 2017-12-07
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Boeing | Various | Airworthiness Directives; The Boeing Company Airplanes |
Unsafe Condition
In-flight failure of the left temperature control valve and control cabin trim air modulating valve.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Replace the left temperature control valve and control cabin trim air modulating valve in accordance with Boeing Alert Service Bulletin 737-21A1203, dated June 8, 2016.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 12 months of the effective date (July 20, 2017).
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Affected Aircraft
The Boeing Company Model 737-800, -900, and -900ER series airplanes.
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 certain The Boeing Company Model 737-800, -900, and -900ER series airplanes. This AD was prompted by reports of in-flight failure of the left temperature control valve and control cabin trim air modulating valve. This AD requires replacing the left temperature control valve and control cabin trim air modulating valve. We are issuing this AD to address the unsafe condition on these products.
Applicability Source Text
Show captured applicability text from the source AD
(c) Applicability
This AD applies to The Boeing Company Model 737-800, -900, and -
900ER series airplanes, certificated in any category, as identified
in Boeing Alert Service Bulletin 737-21A1203, dated June 8, 2016.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 82, Number 114 (Thursday, June 15, 2017)]
[Rules and Regulations]
[Pages 27416-27419]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2017-12172]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2016-9432; Directorate Identifier 2016-NM-116-AD;
Amendment 39-18922; AD 2017-12-07]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
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[[Page 27417]]
SUMMARY: We are adopting a new airworthiness directive (AD) for certain
The Boeing Company Model 737-800, -900, and -900ER series airplanes.
This AD was prompted by reports of in-flight failure of the left
temperature control valve and control cabin trim air modulating valve.
This AD requires replacing the left temperature control valve and
control cabin trim air modulating valve. We are issuing this AD to
address the unsafe condition on these products.
DATES: This AD is effective July 20, 2017.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of July 20,
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-
9432.
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-
9432; 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: Stanley Chen, Aerospace Engineer,
Cabin Safety and Environmental Systems Branch, ANM-150S, FAA, Seattle
Aircraft Certification Office (ACO), 1601 Lind Avenue SW., Renton, WA
98057-3356; phone: 425-917-6585; fax: 425-917-6590; email:
<a href="/cdn-cgi/l/email-protection#126166737c7e776b3c717a777c527473733c757d64"><span class="__cf_email__" data-cfemail="b1c2c5d0dfddd4c89fd2d9d4dff1d7d0d09fd6dec7">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 by adding an AD that would apply to certain The Boeing Company
Model 737-800, -900, and -900ER series airplanes. The NPRM published in
the Federal Register on December 5, 2016 (81 FR 87494). The NPRM was
prompted by reports of in-flight failure of the left temperature
control valve and control cabin trim air modulating valve. The NPRM
proposed to require replacing the left temperature control valve and
control cabin trim air modulating valve. We are issuing this AD to
prevent temperatures in excess of 100 degrees Fahrenheit in the flight
deck or the passenger cabin during cruise, which could lead to the
impairment of the flight crew and prevent continued safe flight and
landing.
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
The Air Line Pilots Association, International and United Airlines
(UAL) stated that they support the NPRM.
Request To Clarify the Unsafe Condition
Boeing requested that we change a sentence in the Discussion
section of the NPRM from ``This condition, if not corrected, could
result . . . .'' to ``This condition, if not corrected or mitigated by
crew completion of the cabin temperature hot procedure under Section
2.8 of the quick reference handbook (QRH), could result. . . .'' Boeing
stated that the cabin temperature hot procedure was created
specifically to address failed open temperature control valves. They
further stated that this procedure is an effective remedy for failed
valves and enhances safety.
We disagree with the request to revise the description of the
unsafe condition in the Discussion section. More than half of the
affected fleets are operated by non-U.S. air carriers, who are not
required to incorporate the revised Flight Crew Operations Manual
(FCOM), which includes the QRH. Since this AD does not require
incorporation of the FCOM, or the QRH, and instead requires replacement
of two control valves, we do not find it appropriate to reference the
QRH as a mitigating factor in the description of the unsafe condition.
We have not changed this AD regarding this issue.
Request To Allow Maintenance Records Review To Determine Installed
Parts
Alaska Airlines (Alaska) asked that we revise paragraph (g) of the
proposed AD, which mandates replacement of certain valves, to state
that a records review is acceptable for compliance with the
requirements of that paragraph (by determining which valves must be
replaced). Alaska noted that a similar statement is included as a note
in Boeing Alert Service Bulletin 737-21A1203, dated June 8, 2016, and
that the note and steps 3.B.1.c. and 3.B.1.d. of the Accomplishment
Instructions of Boeing Alert Service Bulletin 737-21A1203, dated June
8, 2016, are not Required for Compliance (RC). (We note that those
steps state that no further action is required for nondiscrepant
parts.) Alaska indicated that because the NPRM does not include a
similar statement, an airline doing only a records check, and finding
no discrepant parts, could be considered non-compliant.
We agree with the commenter. Paragraph (g) of this AD requires
replacing certain valves in accordance with the Accomplishment
Instructions in Boeing Alert Service Bulletin 737-21A1203, dated June
8, 2016. We did not intend for operators to need an alternative method
of compliance (AMOC) to address the situation described by the
commenter. Therefore, we have revised paragraph (g) of this AD to add
the phrase ``as applicable'' to the requirement for valve replacements
so that operators will not need an AMOC if the correct valve is already
installed.
Request To Correct the Manufacturer Information
UAL stated that the header section of the NPRM referenced the wrong
aircraft manufacturer, reading: ``Proposed Rule: Airworthiness
Directives: Bombardier, Inc. Airplanes.'' UAL noted that it should say
The Boeing Company Airplanes.
We acknowledge the commenter's concern. However, the NPRM correctly
identifies the manufacturer as Boeing, as published in the Federal
Register. It was the docket in the Federal Docket Management System
(FDMS) that incorrectly identified the manufacturer as Bombardier. This
information has been corrected. Therefore, we have not changed this
final rule regarding this issue.
Effect of Winglets on Accomplishment of the Proposed Actions
Aviation Partners Boeing stated that the installation of winglets
per Supplemental Type Certificate (STC)
[[Page 27418]]
ST00830SE does not affect the accomplishment of the manufacturer's
service instructions.
We agree with the commenter that STC ST00830SE does not affect the
accomplishment of the manufacturer's service instructions. Therefore,
the installation of STC ST00830SE does not affect the ability to
accomplish the actions required by this AD. We have not changed this AD
in this regard.
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 this change 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 737-21A1203, dated June
8, 2016. The service information describes procedures for replacing the
left temperature control valve and control cabin trim air modulating
valve, part number 398908-4, with new part number 398908-3 or 398908-5.
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 319 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
----------------------------------------------------------------------------------------------------------------
Replacement of valves.......... 9 work-hours x $85 per $4,800 $5,565 per valve.. $1,775,235 per
hour = $765 per valve. valve.
----------------------------------------------------------------------------------------------------------------
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):
2017-12-07 The Boeing Company: Amendment 39-18922; Docket No. FAA-
2016-9432; Directorate Identifier 2016-NM-116-AD.
(a) Effective Date
This AD is effective July 20, 2017.
(b) Affected ADs
None.
(c) Applicability
This AD applies to The Boeing Company Model 737-800, -900, and -
900ER series airplanes, certificated in any category, as identified
in Boeing Alert Service Bulletin 737-21A1203, dated June 8, 2016.
(d) Subject
Air Transport Association (ATA) of America Code 21, Air
conditioning.
(e) Unsafe Condition
This AD was prompted by reports of in-flight failure of the left
temperature control valve and control cabin trim air modulating
valve. We are issuing this AD to prevent temperatures in excess of
100 degrees Fahrenheit in the flight deck or the passenger cabin
during cruise, which could lead to the impairment of the flight crew
and prevent continued safe flight and landing.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Replacement of the Left Temperature Control Valve and Control Cabin
Trim Air Modulating Valve
Within 60 months after the effective date of this AD, replace
the left temperature control valve and control cabin trim air
modulating valve, as applicable, in accordance with the
Accomplishment Instructions of Boeing Alert Service Bulletin 737-
21A1203, dated June 8, 2016.
(h) Parts Installation Prohibition
As of the effective date of this AD, no person may install a
temperature control valve, part number 398908-4, in either the left
temperature control valve location or the control cabin trim air
modulating valve location on any Model 737-800, -900, or -900ER
airplane.
(i) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Seattle Aircraft Certification Office (ACO),
FAA, has the authority to approve AMOCs for this AD, if requested
using the procedures found in 14
[[Page 27419]]
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 (j) of this AD. Information may be emailed to: <a href="/cdn-cgi/l/email-protection#d1e8fc909f9cfc82b4b0a5a5bdb4fc90929efc909c9e92fc83b4a0a4b4a2a5a291b7b0b0ffb6bea7"><span class="__cf_email__" data-cfemail="dce5f19d9291f18fb9bda8a8b0b9f19d9f93f19d91939ff18eb9ada9b9afa8af9cbabdbdf2bbb3aa">[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, Seattle 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
(i)(4)(i) and (i)(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.
(j) Related Information
For more information about this AD, contact Stanley Chen,
Aerospace Engineer, Cabin Safety and Environmental Systems Branch,
ANM-150S, FAA, Seattle ACO, 1601 Lind Avenue SW., Renton, WA 98057-
3356; phone: 425-917-6585; fax: 425-917-6590; email:
<a href="/cdn-cgi/l/email-protection#d6a5a2b7b8bab3aff8b5beb3b896b0b7b7f8b1b9a0"><span class="__cf_email__" data-cfemail="443730252a28213d6a272c212a042225256a232b32">[email protected]</span></a>.
(k) 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 737-21A1203, dated June 8,
2016.
(ii) Reserved.
(3) For 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>.
(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: <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 June 2, 2017.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2017-12172 Filed 6-14-17; 8:45 am]
BILLING CODE 4910-13-P
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Retrieved: Apr 4, 2026
Rights: U.S. Government Public Domain
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