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[Federal Register Volume 90, Number 26 (Monday, February 10, 2025)]
[Rules and Regulations]
[Pages 9189-9197]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-02376]

=======================================================================
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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-1993; Project Identifier AD-2023-00129-T; 
Amendment 39-22940; AD 2025-02-07]
RIN 2120-AA64

Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2020-03-
20, which applied to certain The Boeing Company Model MD-11, MD-11F, 
and 717-200 airplanes; all Model 737-8 and 737-9 airplanes; all Model 
737-600, -700, -700C, -800, -900, and -900ER series airplanes; certain 
Model 747-400 and 747-400F series airplanes; certain Model 757 and 767 
airplanes; and all Model 777 airplanes. AD 2020-03-20 required revising 
the existing airplane flight manual (AFM) to include a limitation to 
prohibit operations that require less than 0.3 required navigational 
performance (RNP) within a specified area for airplanes having a 
certain multimode receiver (MMR) with certain software installed. This 
AD was prompted by reports from Boeing of simultaneous MMR resets 
related to an error in calculating Coordinated Universal Time (UTC). 
This AD requires the actions in AD 2020-03-20, removes an airplane 
model from the applicability, and would also require installing certain 
MMR operational software (OPS). The FAA is issuing this AD to address 
the unsafe condition on these products.

DATES: This AD is effective March 17, 2025.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of March 17, 
2025.

ADDRESSES: 
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2023-1993; 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 address for Docket Operations is U.S. Department of 
Transportation, Docket Operations, M-30, West Building Ground Floor, 
Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.
    Material Incorporated by Reference:
     For Boeing material 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; website myboeingfleet.com.
     You may view this material 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 regulations.gov under 
Docket No. FAA-2023-1993.

FOR FURTHER INFORMATION CONTACT: Douglas Tsuji, Aviation Safety 
Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-
231-3548; [email protected].

SUPPLEMENTARY INFORMATION: 

Background

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 to supersede AD 2020-03-20, Amendment 39-19844 (85 FR 8717, 
February 18, 2020) (AD 2020-03-20). AD 2020-03-20 applied to certain 
The Boeing Company Model MD-11, MD-11F, and 717-200 airplanes; all 
Model 737-8 and 737-9 airplanes; all Model 737-600, -700, -700C, -800, 
-900, and -900ER series airplanes; certain Model 747-400 and 747-400F 
series airplanes; certain Model 757 and 767 airplanes; and all Model 
777 airplanes. The NPRM published in the Federal Register on December 
12, 2023 (88 FR 86073). The NPRM was prompted by reports from Boeing of 
simultaneous MMR resets related to an error in calculating UTC. In the 
NPRM, the FAA proposed to continue to require the actions in AD 2020-
03-20 and to require installing certain MMR OPS. The FAA is issuing 
this AD to address loss of GPS data and degraded GPS positional 
accuracy, which, during a high-precision approach with this GPS error, 
could result in controlled flight into terrain, and to address UTC 
calculation errors that could result in simultaneous MMR resets on 
multiple airplanes, increased air traffic control workload, and 
consequent reduction in airplane separation and potential for mid-air 
collision.

Discussion of Final Airworthiness Directive

Comments

    The FAA received a comment from Air Line Pilots Association, 
International, who supported the NPRM without change.
    The FAA received additional comments from ten commenters: American 
Airlines, Aviation Partners Boeing (APB), Boeing, Delta Air Lines 
(Delta), FedEx, Korean Air, Ryanair, SIA Engineering, United Parcel 
Service (UPS) Air, and an individual. The following presents the 
comments received on the NPRM and the FAA's response to each comment.

Request for Clarification of Applicability in Regards to Installed MMR 
Part Numbers and Software Versions

    American Airlines requested a revision to paragraph (c) of the 
proposed AD to clarify that only airplanes on which Collins GLU-2100 
MMR having P/N 822-2532-100 and a software version earlier than COL4C-
0087-0003 are installed are affected by the proposed requirements. 
American Airlines suggested revising the text of paragraph (c) of the 
proposed AD to specify only Collins GLU-2100 MMR part number and ``34 
MMR OPS'' software versions that are earlier than the required software 
version.

[[Page 9190]]

    The FAA agrees to clarify which airplane MMR and software 
configurations are affected by the requirements of this AD. The FAA has 
revised paragraph (c) of this AD to specify the Collins CLU-2100 MMR, 
having P/N 822-2532-100, with a software version earlier than COL4C-
0087-0003.

Request To Exclude Certain Configurations of Airplanes

    FedEx requested revising paragraphs (c)(1) through (9) of the 
proposed AD to add the phrase ``having MMRs with OPS software shown in 
Figure 1 to Paragraph (g).'' FedEx explained that without the proposed 
wording, the proposed applicability could lead to unnecessary work on 
airplanes that are already in compliance with the proposed 
requirements.
    The FAA agrees to revise paragraphs (c)(1) through (9) of this AD 
to add clarity on affected airplanes. As stated previously, the FAA has 
revised paragraph (c) of this AD to specify that the applicability 
includes airplanes equipped with Collins GLU-2100 MMR, having P/N 822-
2532-100, with a software version earlier than COL4C-0087-0003.

Request To Align Applicability of This AD With AD 2020-03-20

    Korean Airlines requested a revision to the applicability of 
paragraphs (h) and (i) of the proposed AD to align it with the 
applicability of paragraph (g) of the proposed AD. Korean Airlines 
noted that paragraph (g) of AD 2020-03-20 was applicable to airplanes 
equipped with Collins GLU-2100 MMR having P/N 822-2532-100. Korean 
Airlines requested that the same applicability restriction be applied 
to paragraphs (h) and (i) of the proposed AD.
    The FAA agrees with the request. Paragraphs (h) and (i) of this AD 
are intended only for those airplanes equipped with a Collins GLU-2100 
MMR having P/N 822-2532-100. Paragraphs (h) and (i) of this AD have 
been revised to clarify airplane applicability.

Request To Clarify Affected Configurations

    Ryanair requested clarification on what configuration of Model 737-
600, -700, -700C, -800, and -900 series airplanes are affected by the 
proposed requirements of paragraph (h) of the proposed AD. Ryanair 
pointed out that paragraph (c)(4) of the proposed AD includes all of 
the Model 737-600, 700, -700C, -800, and -900 series airplanes 
regardless of whether a Collins MMR was installed on those airplanes. 
Ryanair contrasted that with paragraphs (g) and (h) of the proposed AD, 
where paragraph (g) restricted the required actions to those airplane 
configurations equipped with the Collins GLU-2100 MMR, P/N 822-2532-
100, with an applicable GLU-2100 OPS. Ryanair noted that paragraph (h) 
of the proposed AD would require installation of the OPS P/N COL4C-
0087-0003, on airplanes identified in paragraphs (h)(1) through (7) of 
the proposed AD, but paragraph (h)(3) of the proposed AD identified the 
Model 737-600, -700, -700C, -800, and -900 series airplanes without 
specifying the Collins MMR configuration. Ryanair explained that OPS P/
N COL4C-0087-0003 is applicable only to Collins MMRs.
    The FAA agrees to revise the applicability for clarification. As 
stated previously, the FAA has revised paragraphs (c) and (h) of this 
AD to specify the affected Collins MMR hardware and software 
configuration. This change results in only that configuration being 
affected by the requirements of this AD.

Request To Clarify Scope of Affected Collins MMRs

    SIA Engineering requested clarification on which Collins MMRs are 
affected by the proposed requirements of paragraph (h) of the proposed 
AD. SIA Engineering stated that paragraph (h) of the proposed AD would 
require installation of the MMR OPS P/N COL4C-0087-0003 or later-
approved software version. SIA Engineering requested information on 
whether the requirements of paragraph (h) of the proposed AD would 
apply only to Collins GLU-2100 MMR, P/N 822-2532-100, that are 
installed on the airplanes identified in paragraphs (h)(1) through (7) 
of the proposed AD, or if the requirements would apply to any other 
Collins MMR installed on those identified airplanes.
    The FAA agrees to clarify. The requirements of paragraph (h) of 
this AD are intended to apply only to the Collins GLU-2100 MMR having 
P/N 822-2532-100 installed on the identified airplanes. As stated 
previously, the FAA has revised paragraphs (c) and (h) of this AD to 
specify the affected Collins MMR hardware and software configuration.

Request To Revise Applicability or Provide Credit

    UPS Airlines requested that airplanes that were delivered with the 
Collins GLU-2100 MMU having OPS P/N COL4C-0087-0003 installed, or 
modified with the same MMU and OPS software via STC ST01943WI, be 
excluded from the applicability of the proposed AD. UPS Airlines also 
stated that if the request for exclusion cannot be granted, the FAA 
provide credit instead and also provide credit for the requirements of 
paragraph (g) of the proposed AD for airplanes if the AFM revision was 
previously removed as authorized via an alternative method of 
compliance (AMOC) to AD 2020-03-20.
    The FAA partially agrees with the request. The intent of this AD is 
to require the software update. The FAA has revised paragraph (c) of 
this AD to restrict the applicability to airplanes with the affected 
Collins MMR software configuration. This change results in having only 
airplanes with that configuration being affected by the requirements of 
this AD. Paragraph (k) of this AD provides for terminating the AFM 
revision required by paragraph (g) of this AD after the software 
installation specified in paragraph (h) or (i) of this AD. Paragraph 
(f) of this AD provides relief for required actions that are 
accomplished before the effective date of this AD. In addition, 
Paragraph (m)(4) has been added to this AD to specify that AMOCs 
approved for AD 2020-03-20 are approved as AMOCs for the corresponding 
provisions of this AD.

Request To Clarify Terminating Action

    American Airlines requested a revision to paragraph (g) of the 
proposed AD to clarify that accomplishing the actions in paragraph (h) 
or (i) of the proposed AD would mean the AFM revision requirement 
specified in paragraph (g) of the proposed AD would not be required.
    The FAA disagrees. The FAA considers paragraphs (f) and (k) of this 
AD to be equivalents to the requested change. Paragraph (f) of this AD 
provides relief for actions done prior to the effective date of this 
AD, and paragraph (k) of this AD specifies that the AFM revision may be 
removed. The AD has not been revised in this regard.

Request To Clarify Contents of Service Bulletins

    American Airlines requested a revision to paragraph (i) of the 
proposed AD to add a phrase that describes the software version 
specified by the requirements bulletins. American Airlines stated that 
this would clarify that the required software for compliance with the 
proposed AD is installed by the steps specified in the requirement 
bulletins.
    The FAA disagrees with revising the AD as suggested by American 
Airlines. This information is described in the Material Incorporated by 
Reference under 1 CFR part 51 section of both the proposed AD and this 
AD; that material

[[Page 9191]]

is required by paragraph (i) of this AD. The FAA has not changed this 
AD in this regard.

Effects of Winglets on Accomplishment of Proposed Actions

    Aviation Partners Boeing stated that the installation of winglets 
per Supplemental Type Certificate (STC) ST00830SE, ST01218SE, or 
ST01920SE does not affect the accomplishment of the manufacturer's 
service instructions.
    The FAA agrees with the commenter that STCs ST00830SE, ST01218SE, 
and ST01920SE do not affect the accomplishment of the manufacturer's 
service instructions. Therefore, the installation of STC ST00830SE, 
ST01218SE, or ST01920SE does not affect the ability to accomplish the 
actions required by this AD. The FAA has not changed this AD in this 
regard.

Request To Provide Information on Which Methods Would Be Approved

    Delta requested clarification on what methods would be approved by 
the Manager, AIR-520, FAA, to meet the requirements for installation 
and check of MMR OPS P/N COL4C-0087-0003 as proposed in paragraph (h) 
of the proposed AD. Delta requested that the installation and check 
procedures identified in STCs ST04436AT and ST04416AT be identified as 
approved methods. Delta suggested adding ``in accordance with 
applicable STCs'' in the second sentence of paragraph (h) of the 
proposed AD.
    The FAA disagrees with the request to revise paragraph (h) of this 
AD to add the phrase ``in accordance with applicable STCs.'' The FAA 
would need to evaluate individual STCs to consider an STC to be an 
acceptable means of compliance that contains the necessary installation 
and check procedures. Operators may use the AMOC procedures specified 
in paragraph (m) of this AD to submit, for example, STC ST04436AT or 
ST04416AT as a proposed AMOC. No change to this AD is necessary in this 
regard.

Request To Clarify Which Airplanes Are Identified in Paragraph (h)(3) 
of This AD

    Delta requested clarification on whether all of the airplanes 
identified in paragraph (h)(3) of the proposed AD would be required to 
do the actions proposed in paragraph (h) of the proposed AD. Delta 
pointed out that, unlike paragraphs (h)(1), (2), (4), (5), and (6) of 
the proposed AD, paragraph (h)(3) of the proposed AD does not identify 
Model 737-600, -700, -700C, -800, and -900 series airplanes as being 
modified by an STC, specifically, STC ST04436AT. Delta also stated that 
it seems Model 737-900ER series airplanes have been omitted from 
paragraph (h)(3) of the proposed AD.
    The FAA provides the following clarification of the airplanes 
affected by paragraph (h)(3) of this AD. Because there are Model 737-
600, -700, -700C, 800, -900, and -900ER series airplanes that had the 
Rockwell Collins GLU-2100 installed by STC and Model 737-900ER series 
airplanes identified by Boeing Alert Requirements Bulletin 737-34A3572 
RB, paragraphs (h)(3) and (i)(2) are intended to be applicable to these 
aircraft, respectively. Paragraph (h) of this AD requires the software 
to be installed in accordance with a method approved by the Manager, 
AIR-520, Continued Operational Safety Branch, FAA. Paragraph (h)(3) of 
this AD has been revised to include Model 737-900ER series airplanes 
that have been modified by STC ST04436AT. Operators may request an AMOC 
in accordance with the procedures specified in paragraph (m) of this 
AD.

Request for Clarification on Which Model 737-8 and -9 Series Airplanes 
Are Affected by Paragraph (i)(1) of This AD

    Delta requested clarification on the Model 737-8 and -9 series 
airplanes identified in paragraph (i)(1) of the proposed AD. Delta 
sought clarity on whether the proposed actions in paragraph (i)(1) of 
the proposed AD are applicable to Model 737-8 and -9 airplanes 
identified in Boeing Alert Requirements Bulletin 737-34A3572 only or 
applicable to any Model 737-8 or -9 series airplane that is equipped 
with a GLU-2100 MMR.
    The FAA provides the following clarification. As indicated in the 
introductory text to paragraph (i) of this AD, paragraph (i)(1) of this 
AD is limited to Model 737-8 and -9 series airplanes equipped with a 
Collins GLU-2100 MMR, part number (P/N) 822-2532-100, having any 
applicable GLU-2100 operational software (OPS). No change to this AD is 
necessary in this regard.

Request To Clarify Affected Model 737-900ER Airplanes for Paragraph 
(i)(2) of This AD

    Delta requested clarification on the Model 737-900ER series 
airplanes identified in paragraph (i)(2) of the proposed AD. Delta 
sought clarity on whether the proposed actions in paragraph (i)(2) of 
the proposed AD are applicable to Model 737-900ER series airplanes 
identified in Boeing Alert Requirements Bulletin 737-34A3573 only or 
applicable to any Model 737-900ER series airplane that is equipped with 
a GLU-2100 MMR. Delta stated that it is concerned that the paragraph, 
as written, would only apply to a subset of 737-900ER series airplanes 
that are identified in the Boeing requirements bulletin and not to 
airplanes that would be modified by STC ST04436AT and subsequently have 
a GLU-2100 MMR installed.
    The FAA provides the following clarification. Paragraph (i)(2) of 
this AD applies to those Model 737-900ER series airplanes identified in 
Boeing Alert Requirements Bulletin 737-34A3572 RB. No change to this AD 
in this regard.

Request To Provide Clarification on Showing Compliance for Actions 
Accomplished Prior to Effective Date

    Delta requested clarification on how to show compliance with the 
proposed requirements in paragraph (h) of the proposed AD. Delta stated 
a concern for airplanes modified to be equipped with the approved part 
number (MMR OPS P/N COL4C-0087-0003 or later version) but were modified 
before the effective date of the AD. Delta requested revising the 
proposed AD to allow a review of airplane maintenance records.
    The FAA provides the following clarification. Airplanes equipped 
with the approved part number (MMR OPS P/N COL4C-0087-0003 or later 
version) are in compliance with this AD. Paragraph (f) of this AD 
provides relief for actions done prior to the effective date of this 
AD. No change to this AD is necessary in this regard.

Request To Remove Model 767-2C From Proposed AD

    Boeing requested that Model 767-2C series airplanes be removed from 
the applicability and other paragraphs of the proposed AD such as in 
the Summary and Background of the NPRM, and figure 1 to paragraph (g) 
of the proposed AD. Boeing explained that the GLU-2100 MMR had not been 
certified for installation or use on Model 767-2C series airplanes.
    The FAA agrees to remove reference to Model 767-2C series airplanes 
from paragraph (c)(7) of this AD and figure 1 to paragraph (g) of this 
AD. The FAA has revised paragraph (c)(7), figure 1 to paragraph (g), 
and paragraph (h)(6) of this AD.

Request To Clarify Software Requirements

    UPS Airlines requested a clarification on the software requirements 
in the third sentence of paragraph (h) of the proposed AD. UPS Airlines 
noted that paragraph (h) of the proposed AD

[[Page 9192]]

referred to ``Boeing software versions'' when defining later-approved 
software versions. UPS Airlines asked if the FAA means MMR OPS software 
versions intended for Boeing airplane models or if the FAA means 
Boeing-approved software versions. UPS Airlines noted that operators 
who used the STCs are using OPS software under a Collins STC, not a 
Boeing STC. UPS Airlines suggested that the FAA either remove the 
reference to Boeing or change the reference to Boeing/Collins.
    The FAA provides the following clarification. The proposed 
requirements would have meant only Boeing-approved software versions. 
The FAA has revised paragraph (h) of this AD to include Collins-
approved software versions.

Conclusion

    The FAA reviewed the relevant data, considered any comments 
received, and determined that air safety requires adopting this AD as 
proposed. Accordingly, the FAA is issuing this AD to address the unsafe 
condition on these products. Except for minor editorial changes, and 
any other changes described previously, this AD is adopted as proposed 
in the NPRM. None of the changes will increase the economic burden on 
any operator.

Material Incorporated by Reference Under 1 CFR Part 51

    The FAA reviewed the following Boeing requirements bulletins:
     Boeing Alert Requirements Bulletin 737-34A3572 RB, dated 
October 15, 2020.
     Boeing Alert Requirements Bulletin 737-34A3573 RB, dated 
August 5, 2020.
     Boeing Alert Requirements Bulletin 777-34A0385 RB, 
Revision 1, dated March 8, 2021.
    This material specifies procedures for installation of MMR OPS part 
number (P/N) COL4C-0087-0003 (or later-approved software P/N) in MMR 1 
and MMR 2, installation of MMR option selection software (OSS) P/N 
BCG27-U000-0730 or BCG48-U000-05W9, and software configuration checks. 
This material also specifies taking concurrent actions, including 
replacement of MMRs, replacement of GPS antennas, and installation of 
additional software.
    These documents are distinct since they apply to different airplane 
models and configurations. This material 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

    The FAA estimates that this AD affects 409 airplanes of U.S. 
registry. The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                        Cost per
              Action                    Labor cost        Parts cost    product        Cost on U.S. operators
----------------------------------------------------------------------------------------------------------------
AFM revision (retained action      1 work-hour x $85              $0          $85  $34,765.
 from AD 2020-03-20).               per hour = $85.
Software installation and check    2 work-hours x $85            265          435  $177,915.
 (new action).                      per hour = $170.
Concurrent actions...............  5 work-hours x $85 =          795        1,220  Up to $498,980.*
                                    $425.
----------------------------------------------------------------------------------------------------------------
* Not all airplanes would be required to do the concurrent actions. However, the FAA does not have an estimate
  of how many airplanes are in a configuration that would require concurrent actions.

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,
    (2) Will not affect intrastate aviation in Alaska, and
    (3) 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.

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:
0
a. Removing Airworthiness Directive (AD) 2020-03-20, Amendment 39-19844 
(85 FR 8717, February 18, 2020); and
0
b. Adding the following new AD:

2025-02-07 The Boeing Company: Amendment 39-22940; Docket No. FAA-
2023-1993; Project Identifier AD-2023-00129-T.

(a) Effective Date

    This airworthiness directive (AD) is effective March 17, 2025.

(b) Affected ADs

    This AD replaces AD 2020-03-20, Amendment 39-19844 (85 FR 8717, 
February 18, 2020) (AD 2020-03-20).

(c) Applicability

    This AD applies to The Boeing Company airplanes, certificated in 
any category, as identified in paragraphs (c)(1) through (9) of this 
AD, on which Collins GLU-2100 MMR, P/N 822-2532-100, with a software 
version earlier than COL4C-0087-0003 is installed.
    (1) Model MD-11 and MD-11F airplanes modified by supplemental 
type certificate (STC) ST01895WI.

[[Page 9193]]

    (2) Model 717-200 airplanes modified by STC ST04416AT.
    (3) All Model 737-8 and 737-9 airplanes.
    (4) All Model 737-600, -700, -700C, -800, -900, and -900ER 
series airplanes.
    (5) Model 747-400 and 747-400F series airplanes modified by STC 
ST01892WI.
    (6) Model 757-200, -200PF, -200CB, and -300 series airplanes 
modified by STC ST04436AT.
    (7) Model 767-200, -300, -300F, and -400ER series airplanes 
modified by STC ST04436AT or ST01883WI.
    (8) All Model 777-200, -200LR, -300, and -300ER series 
airplanes.
    (9) All Model 777F series airplanes.

(d) Subject

    Air Transport Association (ATA) of America Code 34, Navigation.

(e) Unsafe Condition

    This AD was prompted by reports of the loss of global 
positioning system (GPS) data or degraded GPS positional accuracy 
and additional reports of an error in calculating Coordinated 
Universal Time (UTC) while using a certain multi-mode receiver (MMR) 
with certain software installed. The FAA is issuing this AD to 
address loss of GPS data and degraded GPS positional accuracy, 
which, during a high-precision approach with this GPS error, could 
result in controlled flight into terrain, and to address UTC 
calculation errors that could result in simultaneous MMR resets on 
multiple airplanes, increased air traffic control workload, and 
consequent reduction in airplane separation and potential for mid-
air collision.

(f) Compliance

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

(g) Retained Airplane Flight Manual (AFM) Revision, With No Changes

    This paragraph restates the requirements of paragraph (g) of AD 
2020-03-20, with no changes. For airplanes equipped with Collins 
GLU-2100 MMR, part number (P/N) 822-2532-100, having any applicable 
GLU-2100 operational software (OPS) identified in figure 1 to 
paragraph (g) of this AD installed: At the applicable time specified 
in paragraphs (g)(1) and (2) of this AD, revise the limitations or 
certificate limitations section, as applicable, of the existing AFM 
to include the information specified in figure 2 to paragraph (g) of 
this AD and revise the procedures or normal procedures section, as 
applicable, of the existing AFM to include the information specified 
in figure 3 to paragraph (g) of this AD. This may be done by 
inserting a copy of figures 2 and 3 to paragraph (g) of this AD into 
the existing AFM.
    (1) For Model 737-8 and 737-9 airplanes: Before further flight.
    (2) For all airplanes except Model 737-8 and 737-9 airplanes: 
Within 7 days after February 18, 2020 (the effective date of AD 
2020-03-20).
BILLING CODE 4910-13-P

Figure 1 to Paragraph (g)--Affected OPS Software
[GRAPHIC] [TIFF OMITTED] TR10FE25.000

[[Page 9194]]

Figure 2 to Paragraph (g)--AFM--Limitations or Certificate Limitations
[GRAPHIC] [TIFF OMITTED] TR10FE25.001

[[Page 9195]]

Figure 2 to Paragraph (g)--AFM--Limitations or Certificate Limitations 
Continued
[GRAPHIC] [TIFF OMITTED] TR10FE25.002

[[Page 9196]]

Figure 3 to Paragraph (g)--AFM--Procedures or Normal Procedures
[GRAPHIC] [TIFF OMITTED] TR10FE25.003

BILLING CODE 4910-13-C

(h) Software Installation for Certain Airplanes

    For airplanes identified in paragraphs (h)(1) through (7) of 
this AD with Collins GLU-2100 MMR, part number (P/N) 822-2532-100, 
having any applicable GLU-2100 operational software (OPS): Within 12 
months after the effective date of this AD, install MMR OPS P/N 
COL4C-0087-0003, or later-approved software version, and do a 
software configuration check to confirm that P/N COL4C-0087-0003 or 
later-approved software version is installed. Both the installation 
and the check must be done in accordance with a method approved by 
the Manager, AIR-520, Continued Operational Safety Branch, FAA. 
Later-approved software versions are those Boeing or Collins 
software versions that are approved as a replacement for MMR OPS P/N 
COL4C-0087-0003 and are approved as part of the type design by the 
FAA or by The Boeing Company Organization Designation Authorization 
(ODA).
    (1) Model MD-11 and MD-11F airplanes modified by STC ST01895WI.
    (2) Model 717-200 airplanes modified by STC ST04416AT.
    (3) Model 737-600, -700, -700C, -800, -900, and -900ER series 
airplanes modified by STC ST04436AT.
    (4) Model 747-400 and 747-400F series airplanes modified by STC 
ST01892WI.
    (5) Model 757-200, -200PF, -200CB, and -300 series airplanes 
modified by STC ST04436AT.
    (6) Model 767-200, -300, -300F, and -400ER series airplanes 
modified by STC ST04436AT or ST01883WI.
    (7) Model 777-200, -200LR, and -300 series airplanes.

(i) Software Installation for Certain Other Airplanes

    For Model 737-8 and -9 airplanes, Model 737-900ER series 
airplanes, and Model 777-300ER and 777F series airplanes equipped 
with Collins GLU-2100 MMR, part number (P/N) 822-2532-100, having 
any applicable GLU-2100 operational software (OPS): Within 12 months 
after the effective date of this AD, except as specified in 
paragraph (j) of this AD, do all applicable actions identified in, 
and in accordance with, the Accomplishment Instructions of the 
applicable requirements bulletin identified in paragraphs (i)(1) 
through (3) of this AD.
    (1) For Model 737-8 and -9 airplanes: Boeing Alert Requirements 
Bulletin 737-34A3572 RB, dated October 15, 2020.
    Note 1 to paragraph (i)(1): Guidance for accomplishing the 
actions required by paragraph (i)(1) of this AD can be found in 
Boeing Alert Service Bulletin 737-34A3572, dated October 15, 2020, 
which is referred to in Boeing Alert Requirements Bulletin 737-
34A3572 RB, dated October 15, 2020.
    (2) For Model 737-900ER series airplanes: Boeing Alert 
Requirements Bulletin 737-34A3573 RB, dated August 5, 2020.
    Note 2 to paragraph (i)(2): Guidance for accomplishing the 
actions required by paragraph (i)(2) of this AD can be found in 
Boeing Alert Service Bulletin 737-34A3573, dated August 5, 2020, 
which is referred to in Boeing Alert Requirements Bulletin 737-
34A3573 RB, dated August 5, 2020.
    (3) For Model 777-300ER and 777F series airplanes: Boeing Alert 
Requirements Bulletin 777-34A0385 RB, Revision 1, dated March 8, 
2021.
    Note 3 to paragraph (i)(3): Guidance for accomplishing the 
actions required by paragraph (i)(3) of this AD can be found in 
Boeing Alert Service Bulletin 777-34A0385, Revision 1, dated March 
8, 2021, which is referred to in Boeing Alert Requirements Bulletin 
777-34A0385 RB, Revision 1, dated March 8, 2021.

(j) Exceptions to Service Information Specifications

    Where the requirements bulletins identified in paragraphs (i)(1) 
through (3) of this AD specify installing MMR option selection 
software (OSS) P/N BCG27-U000-0730 or BCG48-U000-05W9 and doing the 
associated software configuration check, this AD does not require 
those actions.

(k) Terminating Action

    After accomplishing the actions required by paragraph (h) or (i) 
of this AD, as applicable, you may remove the AFM revision required 
by paragraph (g) of this AD.

(l) Credit for Previous Actions

    This paragraph provides credit for the actions required by 
paragraph (i)(3) of this AD, if the actions were performed before 
the effective date of this AD using Boeing Alert Requirements 
Bulletin 777-34A0385 RB, dated August 7, 2020.

(m) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, AIR-520, Continued Operational Safety 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 14 
CFR 39.19, send your request to your principal inspector or 
responsible Flight Standards 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 
(n)(1) 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 responsible Flight Standards 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 Company ODA that has been authorized 
by the Manager, AIR-520, Continued Operational Safety 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.

[[Page 9197]]

    (4) AMOCs approved for AD 2020-03-20 are approved as AMOCs for 
the corresponding provisions of this AD.

(n) Related Information

    (1) For more information about this AD, contact Douglas Tsuji, 
Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 
98198; phone: 206-231-3548; [email protected].
    (2) Material identified in this AD that is not incorporated by 
reference is available at the addresses specified in paragraph 
(o)(3) of this AD.

(o) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference of the material listed in this paragraph 
under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this material as applicable to do the actions 
required by this AD, unless the AD specifies otherwise.
    (i) Boeing Alert Requirements Bulletin 737-34A3572 RB, dated 
October 15, 2020.
    (ii) Boeing Alert Requirements Bulletin 737-34A3573 RB, dated 
August 5, 2020.
    (iii) Boeing Alert Requirements Bulletin 777-34A0385 RB, 
Revision 1, dated March 8, 2021.
    (3) For Boeing material 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; website myboeingfleet.com.
    (4) You may view this material 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.
    (5) You may view this material at the National Archives and 
Records Administration (NARA). For information on the availability 
of this material at NARA, visit www.archives.gov/federal-register/cfr/[email protected]">www.archives.gov/federal-register/cfr/[email protected].

    Issued on January 16, 2025.
Suzanne Masterson,
Deputy Director, Integrated Certificate Management Division, Aircraft 
Certification Service.
[FR Doc. 2025-02376 Filed 2-7-25; 8:45 am]
BILLING CODE 4910-13-P
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