AD 2021-07-02

Recurring final rule

Airworthiness Directives; The Boeing Company Airplanes

AD Number
2021-07-02
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2021-0190
FR Citation
86 FR 17515

Applicability

TypeManufacturerModelDetails
aircraft Boeing Various Airworthiness Directives; The Boeing Company Airplanes

Unsafe Condition

The pitot heat switch is not always set to ON, which could result in misleading air data. The failure to activate the manually activated pitot anti-icing system likely resulted in misleading air data that contributed to an accident and three incidents involving Boeing Model 737 airplanes.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Replacement of pitot anti-icing system components, installation of a junction box and wiring provisions, repetitive testing of the anti-icing system, and applicable on-condition actions.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within 50 flight hours

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

The Boeing Company Model 737-200 series airplanes, variable numbers PK625 through PK627 inclusive.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

The FAA is adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-200 series airplanes. This AD was prompted by reports indicating that the pitot heat switch is not always set to ON, which could result in misleading air data. This AD requires replacement of pitot anti-icing system components, installation of a junction box and wiring provisions, repetitive testing of the anti- icing system, and applicable on-condition actions. The FAA is 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 737-200 series 
airplanes, having variable numbers PK625 through PK627 inclusive, 
certificated in any category.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 86, Number 63 (Monday, April 5, 2021)]
[Rules and Regulations]
[Pages 17515-17518]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2021-06896]


-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0190; Project Identifier AD-2020-01348-T; 
Amendment 39-21479; AD 2021-07-02]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

-----------------------------------------------------------------------

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain The Boeing Company Model 737-200 series airplanes. This AD was 
prompted by reports indicating that the pitot heat switch is not always 
set to ON, which could result in misleading air data. This AD requires 
replacement of pitot anti-icing system components, installation of a 
junction box and wiring provisions, repetitive testing of the anti-
icing system, and applicable on-condition actions. The FAA is issuing 
this AD to address the unsafe condition on these products.

DATES: This AD is effective April 20, 2021.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of April 20, 
2021.
    The Director of the Federal Register approved the incorporation by 
reference of certain other publications listed in this AD as of June 
26, 2019 (84 FR 23458, May 22, 2019).
    The FAA must receive comments on this AD by May 20, 2021.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
    <bullet> Federal eRulemaking Portal: Go to <a href="https://www.regulations.gov">https://www.regulations.gov</a>. Follow the instructions for submitting comments.
    <bullet> Fax: 202-493-2251.
    <bullet> Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC 20590.
    <bullet> Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    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 service information at the FAA, Airworthiness Products 
Section, Operational Safety Branch, 2200 South 216th St., Des Moines, 
WA. For information on the availability of this material at the FAA, 
call 206-231-3195. It is also available at <a href="https://www.regulations.gov">https://www.regulations.gov</a> 
by searching for and locating Docket No. FAA-2021-0190.

Examining the AD Docket

    You may examine the AD docket at <a href="https://www.regulations.gov">https://www.regulations.gov</a> by 
searching for and locating Docket No. FAA-2021-0190; or in person at 
Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays. The AD docket contains this final rule, any 
comments received, and other information. The street address for the 
Docket Operations is listed above.

FOR FURTHER INFORMATION CONTACT: Jeffrey W. Palmer, Aerospace Engineer, 
Systems and Equipment Section, FAA, Los Angeles ACO Branch, 3960 
Paramount Boulevard, Lakewood, CA 90712-4137; phone: 562-627-5851; fax: 
562-627-5210; email: <a href="/cdn-cgi/l/email-protection#3e545b58584c5b471049104e5f52535b4c7e585f5f10595148"><span class="__cf_email__" data-cfemail="ec86898a8a9e8995c29bc29c8d8081899eac8a8d8dc28b839a">[email&#160;protected]</span></a>.

SUPPLEMENTARY INFORMATION:

Background

    The FAA has received reports indicating that the pitot heat switch 
is not always set to ON, which could result in misleading air data. The 
failure to activate the manually activated pitot anti-icing system 
likely resulted in misleading air data that contributed to an accident 
and three incidents involving Boeing Model 737 airplanes. This 
condition, if not addressed, could result in the air data sensors not 
being heated, which could allow ice to form on the sensors and cause 
erroneous air data. This erroneous air data can lead to loss of crew 
situational awareness and could ultimately result in the inability to 
maintain continued safe flight and landing.

FAA's Determination

    The FAA is issuing this AD because the agency has determined the 
unsafe condition described previously is likely to exist or develop in 
other products of the same type design.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Boeing Alert Service Bulletin 737-30A1064, 
Revision 2, dated June 26, 2020. The service information describes 
procedures for replacement and repetitive testing of the

[[Page 17516]]

P5-9 window and pitot heat module, and changing the anti-icing system 
to automatically supply power to heat the air data sensors.
    This AD also requires Boeing Service Bulletin 737-30-1067, Revision 
1, dated May 4, 2017; and Boeing Service Bulletin 737-30-1068, Revision 
1, dated May 4, 2017, which the Director of the Federal Register 
approved for incorporation by reference as of June 26, 2019 (84 FR 
23458, May 22, 2019).
    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.

Minimum Equipment List (MEL) Provision

    The FAA allows operators to utilize a MEL provision for time-
limited operation with certain equipment inoperative, after which the 
system must be fully restored. (See 14 CFR 91.213, 121.628, 125.201, 
and 129.14.) This AD continues to allow use of an existing FAA-approved 
MEL even if the modified air data probe heat (ADPH) system is 
inoperable, so long as the operator's existing FAA-approved MEL has a 
provision to allow for this inoperability.

AD Requirements

    This AD requires accomplishing the actions identified as ``RC'' 
(required for compliance) in the Accomplishment Instructions of Boeing 
Alert Service Bulletin 737-30A1064, Revision 2, dated June 26, 2020, 
described previously, except as discussed under ``Differences Between 
this AD and the Service Information,'' and except for any differences 
identified as exceptions in the regulatory text of this AD.
    This AD also requires accomplishing the actions specified in Boeing 
Service Bulletin 737-30-1067, Revision 1, dated May 4, 2017; and Boeing 
Service Bulletin 737-30-1068, Revision 1, dated May 4, 2017, described 
previously.
    For information on the procedures and compliance times, see this 
service information at <a href="https://www.regulations.gov">https://www.regulations.gov</a> by searching for and 
locating Docket No. FAA-2021-0190.

Differences Between This AD and the Service Information

    The FAA previously issued AD 2019-09-01, Amendment 39-19635 (84 FR 
23458, May 22, 2019) (AD 2019-09-01), which applies to the airplanes 
identified in Boeing Alert Service Bulletin 737-30A1064, Revision 1, 
dated October 18, 2017. This AD requires using Boeing Alert Service 
Bulletin 737-30A1064, Revision 2, dated June 26, 2020, which adds Model 
737-200 series airplanes having variable numbers PK625 through PK627 
inclusive to the effectivity. The unsafe condition and requirements are 
the same for this AD and AD 2019-09-01. This AD therefore applies only 
to the 737-200 series airplanes having variable numbers PK625 through 
PK627 inclusive.

Justification for Immediate Adoption and Determination of the Effective 
Date

    Section 553(b)(3)(B) of the Administrative Procedure Act (APA) (5 
U.S.C. 551 et seq.) authorizes agencies to dispense with notice and 
comment procedures for rules when the agency, for ``good cause,'' finds 
that those procedures are ``impracticable, unnecessary, or contrary to 
the public interest.'' Under this section, an agency, upon finding good 
cause, may issue a final rule without providing notice and seeking 
comment prior to issuance. Further, section 553(d) of the APA 
authorizes agencies to make rules effective in less than thirty days, 
upon a finding of good cause.
    There are currently no U.S.-registered airplanes affected by this 
AD. Accordingly, notice and opportunity for prior public comment are 
unnecessary, pursuant to 5 U.S.C. 553(b)(3). In addition, for the 
foregoing reason(s), the FAA finds that good cause exists pursuant to 5 
U.S.C. 553(d) for making this amendment effective in less than 30 days.

Comments Invited

    The FAA invites you to send any written data, views, or arguments 
about this final rule. Send your comments to an address listed under 
ADDRESSES. Include Docket No. FAA-2021-0190 and Project Identifier AD-
2020-01348-T at the beginning of your comments. The most helpful 
comments reference a specific portion of the final rule, explain the 
reason for any recommended change, and include supporting data. The FAA 
will consider all comments received by the closing date and may amend 
this final rule because of those comments.
    Except for Confidential Business Information (CBI) as described in 
the following paragraph, and other information as described in 14 CFR 
11.35, the FAA will post all comments received, without change, to 
<a href="https://www.regulations.gov">https://www.regulations.gov</a>, including any personal information you 
provide. The agency will also post a report summarizing each 
substantive verbal contact received about this final rule.

Confidential Business Information

    CBI is commercial or financial information that is both customarily 
and actually treated as private by its owner. Under the Freedom of 
Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public 
disclosure. If your comments responsive to this AD contain commercial 
or financial information that is customarily treated as private, that 
you actually treat as private, and that is relevant or responsive to 
this AD, it is important that you clearly designate the submitted 
comments as CBI. Please mark each page of your submission containing 
CBI as ``PROPIN.'' The FAA will treat such marked submissions as 
confidential under the FOIA, and they will not be placed in the public 
docket of this AD. Submissions containing CBI should be sent to Jeffrey 
W. Palmer, Aerospace Engineer, Systems and Equipment Section, FAA, Los 
Angeles ACO Branch, 3960 Paramount Boulevard, Lakewood, CA 90712-4137; 
phone: 562-627-5851; fax: 562-627-5210; email: 
<a href="/cdn-cgi/l/email-protection#3a505f5c5c485f43144d144a5b56575f487a5c5b5b145d554c"><span class="__cf_email__" data-cfemail="026867646470677b2c752c72636e6f6770426463632c656d74">[email&#160;protected]</span></a>. Any commentary that the FAA receives that is 
not specifically designated as CBI will be placed in the public docket 
for this rulemaking.

Regulatory Flexibility Act

    The requirements of the Regulatory Flexibility Act (RFA) do not 
apply when an agency finds good cause pursuant to 5 U.S.C. 553 to adopt 
a rule without prior notice and comment. Because the FAA has determined 
that it has good cause to adopt this rule without notice and comment, 
RFA analysis is not required.

Costs of Compliance

    Currently, there are no affected U.S.-registered airplanes. For any 
affected airplane that is imported and placed on the U.S. Register in 
the future, the FAA provides the following cost estimates to comply 
with this AD:

[[Page 17517]]



                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                 Action                           Labor cost            Parts cost         Cost per product
----------------------------------------------------------------------------------------------------------------
Replacement (Boeing Alert Service         6 work-hours x $85 per                  $0  $510.
 Bulletin 737-30A1064).                    hour = $510.
Repetitive tests (Boeing Alert Service    5 work-hours x $85 per                   0  $425 per inspection cycle.
 Bulletin 737-30A1064).                    hour = $425 per
                                           inspection cycle.
J18 Junction box installation (Boeing     Up to 75 work-hours x $85           23,614  Up to $29,989.
 Service Bulletin 737-30-1067).            per hour = Up to $6,375.
Installation of wire provisions (Boeing   Up to 193 work-hours x $85           4,800  Up to $21,205.
 Service Bulletin 737-30-1068).            per hour = Up to $16,405.
----------------------------------------------------------------------------------------------------------------

    The FAA has received no definitive data that would enable providing 
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.
    The FAA is 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, and
    (2) Will not affect intrastate aviation in Alaska.

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:

2021-07-02 The Boeing Company: Amendment 39-21479; Docket No. FAA-
2021-0190; Project Identifier AD-2020-01348-T.

(a) Effective Date

    This airworthiness directive (AD) is effective April 20, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company Model 737-200 series 
airplanes, having variable numbers PK625 through PK627 inclusive, 
certificated in any category.

(d) Subject

    Air Transport Association (ATA) of America Code 30, Ice and rain 
protection.

(e) Unsafe Condition

    This AD was prompted by reports indicating that the pitot heat 
switch is not always set to ON, which could result in misleading air 
data. The FAA is issuing this AD to address misleading air data, 
which can lead to loss of crew situational awareness and could 
ultimately result in the inability to maintain continued safe flight 
and landing.

(f) Compliance

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

(g) Actions for Group 6 Airplanes

    Except as specified by paragraph (i) of this AD, for airplanes 
identified as Group 6 in Boeing Alert Service Bulletin 737-30A1064, 
Revision 2, dated June 26, 2020: At the applicable times specified 
in paragraph 1.E., ``Compliance,'' of Boeing Alert Service Bulletin 
737-30A1064, Revision 2, dated June 26, 2020, do all applicable 
actions identified as ``RC'' (required for compliance) in, and in 
accordance with, the Accomplishment Instructions of Boeing Alert 
Service Bulletin 737-30A1064, Revision 2, dated June 26, 2020.

(h) Concurrent Requirements

    Except as specified by paragraph (i) of this AD: Prior to or 
concurrently with the actions required by paragraph (g) of this AD, 
install a new J18 junction box to change the anti-icing system, in 
accordance with the Accomplishment Instructions of Boeing Service 
Bulletin 737-30-1067, Revision 1, dated May 4, 2017, and install 
wiring provisions to the anti-icing system, in accordance with the 
Accomplishment Instructions of Boeing Service Bulletin 737-30-1068, 
Revision 1, dated May 4, 2017.

(i) Exceptions to Service Information Specifications

    (1) Where Boeing Alert Service Bulletin 737-30A1064, Revision 2, 
dated June 26, 2020, uses the phrase ``the Revision 2 date of this 
service bulletin,'' this AD requires using ``the effective date of 
this AD.''
    (2) Where Boeing Service Bulletin 737-30-1067, Revision 1, dated 
May 4, 2017, specifies contacting Boeing for repair instructions: 
This AD requires doing the repair before further flight using a 
method approved in accordance with the procedures specified in 
paragraph (l) of this AD.

(j) Credit for Previous Actions

    This paragraph provides credit for the actions specified in 
paragraph (g) of this AD, if those actions were performed before the 
effective date of this AD using Boeing Alert Service Bulletin 737-
30A1064, Revision 1, dated October 18, 2017, which was incorporated 
by reference in AD 2019-09-01, Amendment 39-19635, (84 FR 23458, May 
22, 2019).

(k) Minimum Equipment List (MEL)

    In the event that the air data probe heat (ADPH) system as 
modified by this AD is inoperable, an airplane may be operated as 
specified in the operator's existing FAA-approved MEL, provided the 
operator's existing FAA-approved MEL includes provisions that 
address the modified ADPH system.

(l) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Los Angeles ACO Branch, FAA, has the authority 
to approve AMOCs for this AD, if requested using the procedures 
found in 14 CFR 39.19. In accordance with

[[Page 17518]]

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 certification office, 
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#96afbbd7d8dbbbdad7d7d5d9bbd7dbd9d5bbc4f3e7e3f3e5e2e5d6f0f7f7b8f1f9e0"><span class="__cf_email__" data-cfemail="1a23375b545737565b5b5955375b57555937487f6b6f7f696e695a7c7b7b347d756c">[email&#160;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 Branch, FAA, 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 
(l)(4)(i) and (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.

(m) Related Information

    (1) For more information about this AD, contact Jeffrey W. 
Palmer, Aerospace Engineer, Systems and Equipment Section, FAA, Los 
Angeles ACO Branch, 3960 Paramount Boulevard, Lakewood, CA 90712-
4137; phone: 562-627-5851; fax: 562-627-5210; email: 
<a href="/cdn-cgi/l/email-protection#2d47484b4b5f4854035a035d4c4140485f6d4b4c4c034a425b"><span class="__cf_email__" data-cfemail="6c06090a0a1e0915421b421c0d0001091e2c0a0d0d420b031a">[email&#160;protected]</span></a>.
    (2) Service information identified in this AD that is not 
incorporated by reference is available at the addresses specified in 
paragraphs (n)(5) and (6) 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 this AD specifies otherwise.
    (3) The following service information was approved for IBR on 
April 20, 2021.
    (i) Boeing Alert Service Bulletin 737-30A1064, Revision 2, dated 
June 26, 2020.
    (ii) [Reserved]
    (4) The following service information was approved for IBR on 
June 26, 2019 (84 FR 23458, May 22, 2019).
    (i) Boeing Service Bulletin 737-30-1067, Revision 1, dated May 
4, 2017.
    (ii) Boeing Service Bulletin 737-30-1068, Revision 1, dated May 
4, 2017.
    (5) 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>.
    (6) You may view this service information at the FAA, 
Airworthiness Products Section, Operational Safety Branch, 2200 
South 216th St., Des Moines, WA. For information on the availability 
of this material at the FAA, call 206-231-3195.
    (7) 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, email <a href="/cdn-cgi/l/email-protection#90f6f5f4e2f5f7befcf5f7f1fcd0fef1e2f1bef7ffe6"><span class="__cf_email__" data-cfemail="26404342544341084a4341474a664847544708414950">[email&#160;protected]</span></a>, or go to: <a href="https://www.archives.gov/federal-register/cfr/ibr-locations.html">https://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.

    Issued on March 17, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-06896 Filed 4-2-21; 8:45 am]
BILLING CODE 4910-13-P

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