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Published 2012-04-26 · Federal Register document 2012-9713

Airworthiness Directives; The Boeing Company Airplanes

Publication summary

We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series airplanes equipped with analog transient suppression devices (ATSDs) installed in accordance with Supplemental Type Certificate ST00146BO. This AD was prompted by multiple reports of corrosion on ATSDs. This AD requires revising the maintenance program to incorporate certain limitations. We are issuing this AD to detect and correct corrosion on ATSDs, which could result in the loss of high voltage transient protection (e.g., lightning protection) in the fuel tanks and consequent fuel tank explosion and loss of the airplane.

Why this record is shown

Source: Federal Register annual FAA metadata. Acquired 2026-09-03T22:23:39.502075+00:00. The title, summary and date are source facts.

Source revision
federal_register_ad_metadata_2012-08bffa249ae9a205
Source row
results[142]
Raw source SHA-256
08bffa249ae9a2053bbfc0d74663d089914e83fb91f9bc4c8409ea28239f6875

Final-rule publication

Recorded publication clauses

AD identifier printed in this edition
2012-08-17
Effective date printed in this edition
2012-05-31
Read 11 complete recorded clauses
Effective Date
(a) Effective Date

    This AD is effective May 31, 2012.

Exact source excerpt. Text positions 7748–7808, end exclusive, in the original decoded publication. SHA-256: 445e0af8c623e2b65c87fb4bda23aef33841cef0a7161febb8dbe515f23fd6c5

Affected ADs
(b) Affected ADs

    None.

Exact source excerpt. Text positions 7808–7837, end exclusive, in the original decoded publication. SHA-256: 871a4afc60ceeae06e8010585055188633d616078500c45937092bfe892239c0

Applicability wording · Applicability
(c) Applicability

    (1) This AD applies to The Boeing Company Model 737-100, -200, -
200C, -300, -400, and -500 series airplanes, certificated in any 
category, with an original airworthiness certificate or original 
export certificate of airworthiness issued before September 26, 
2011, equipped with analog transient suppression devices (ATSDs) 
installed in accordance with Supplemental Type Certificate 
ST00146BO. http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/2399C433BB10CF1085256CCB00601A12?OpenDocument&Highlight=st00146bo
    (2) This AD requires revisions to certain operator maintenance 
documents to include new actions (e.g., inspections and/or Critical 
Design Configuration Control Limitations (CDCCLs). Compliance with 
these actions is required by 14 CFR 91.403(c). For airplanes that 
have been previously modified, altered, or repaired in the areas 
addressed by these inspections, the operator may not be able to 
accomplish the inspections described in the revisions. In this 
situation, to comply with 14 CFR 91.403(c), the operator must 
request approval for an alternative method of compliance (AMOC) 
according to paragraph (i) of this AD. The request should include a 
description of changes to the required actions that will ensure the 
continued operational safety of the airplane.

Exact source excerpt. Text positions 7837–9168, end exclusive, in the original decoded publication. SHA-256: 477a2e96fc0be1115a0e2851b1cae2c40a802d56b78bfb3c5e20ea3ab2431c09

Subject
(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 2841, Fuel Quantity Indicator.

Exact source excerpt. Text positions 9168–9305, end exclusive, in the original decoded publication. SHA-256: cbb02a144268b2b5559a8c8803b87c26c0c25cd70ac52a5f95cd21b804803c03

Unsafe Condition
(e) Unsafe Condition

    This AD was prompted by multiple reports of corrosion on ATSDs. 
We are issuing this AD to detect and correct corrosion on ATSDs, 
which could result in the loss of high voltage transient protection 
(e.g., lightning protection) in the fuel tanks and consequent fuel 
tank explosion and loss of the airplane.

Exact source excerpt. Text positions 9305–9641, end exclusive, in the original decoded publication. SHA-256: 7d4c876fd127cd97a72d4878c3dda91ba9a7f0e757c06a104c0609bc384da90b

Compliance
(f) Compliance

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

Exact source excerpt. Text positions 9641–9743, end exclusive, in the original decoded publication. SHA-256: 00fbfa31932483f627d0ce0a11cbd2e35e15d9231842b91ac85623ce533912d3

Maintenance Program Revision
(g) Maintenance Program Revision

    Within 3 months after the effective date of this AD, revise the 
maintenance program to incorporate the limitations specified in 
Goodrich Principal Instructions for Continued Airworthiness Manual 
for the Analog Transient Suppression Device Installation Applicable 
to Boeing 737-100 through -500 Airplanes Supplemental Type 
Certificate--ST00146BO, Document T3044-0010-0101, Revision D, dated 
September 26, 2011. The initial compliance time for accomplishing 
each task is at the applicable

[[Page 24833]]

time specified in Goodrich Principal Instructions for Continued 
Airworthiness Manual for the Analog Transient Suppression Device 
Installation Applicable to Boeing 737-100 through -500 Airplanes 
Supplemental Type Certificate--ST00146BO, Document T3044-0010-0101, 
Revision D, dated September 26, 2011, or within 18 months after the 
effective date of this AD, whichever occurs later.

    Note 1 to paragraph (g) of this AD:  Components that have been 
identified as airworthy or installed on the affected airplanes 
before the revision of the maintenance program, as required by 
paragraph (g) of this AD, do not need to be reworked in accordance 
with the CDCCLs. However, once the maintenance program has been 
revised, paragraph (g) of this AD requires that future maintenance 
actions on these components must follow the CDCCLs.

Exact source excerpt. Text positions 9743–11129, end exclusive, in the original decoded publication. SHA-256: 7f98e2b31940f7984e873ec4b1ee8e3e7a049b8edff45a35751f4f4debbc9a27

No Alternative Actions Intervals, and/or Critical Design Configuration Control Limitations
(h) No Alternative Actions Intervals, and/or Critical Design 
Configuration Control Limitations

    After accomplishing the revision required by paragraph (g) of 
this AD, no alternative actions (e.g., inspections), intervals, and/
or CDCCLs may be used other than those specified in Goodrich 
Principal Instructions for Continued Airworthiness Manual for the 
Analog Transient Suppression Device Installation Applicable to 
Boeing 737-100 through -500 Airplanes Supplemental Type 
Certificate--ST00146BO, Document
    T3044-0010-0101, Revision D, dated September 26, 2011, unless 
the actions, intervals, and/or CDCCLs are approved as an AMOC in 
accordance with the procedures specified in paragraph (i) of this 
AD.

Exact source excerpt. Text positions 11129–11850, end exclusive, in the original decoded publication. SHA-256: 0f1667649b34819acede087019620273efadaa58a70db2d009f01879adab9679

Alternative Methods of Compliance
(i) Alternative Methods of Compliance

    (1) The Manager, Boston Aircraft Certification Office (ACO), 
FAA, has the authority to approve AMOCs for this AD, if requested 
using the procedures found in 14 CFR 39.19. In accordance with 14 
CFR 39.19, send your request to your principal inspector or local 
Flight Standards District Office, as appropriate. If sending 
information directly to the manager of the ACO, send it to the 
attention of the person identified in the Related Information 
section of this AD.
    (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.

Exact source excerpt. Text positions 11850–12583, end exclusive, in the original decoded publication. SHA-256: ceb5c0a515edf190301d640533bf6bacf62f539de6c0a8477ef6708d9c0ecdc1

Related Information
(j) Related Information

    For more information about this AD, contact Marc Ronell, 
Aerospace Engineer, Engine and Propeller Directorate, ANE-150, FAA, 
New England Aircraft Certification Office, 12 New England Executive 
Park, Burlington, Massachusetts 01803; phone: 781-238-7776; fax: 
781-238-7170; email: [email protected].

Exact source excerpt. Text positions 12583–12915, end exclusive, in the original decoded publication. SHA-256: 14e60c77c2f3de2f80479537f87a3057c5bc7a9caea241b4e84e305c0b853e07

Material Incorporated by Reference
(k) Material Incorporated by Reference

    (1) You must use the following service information to do the 
actions required by this AD, unless the AD specifies otherwise. The 
Director of the Federal Register approved the incorporation by 
reference (IBR) of the following service information under 5 U.S.C. 
552(a) and 1 CFR part 51.
    (i) Goodrich Principal Instructions for Continued Airworthiness 
Manual for the Analog Transient Suppression Device Installation 
Applicable to Boeing 737-100 through -500 Airplanes Supplemental 
Type Certificate--ST00146BO, Document T3044-0010-0101, Revision D, 
dated September 26, 2011.
    (2) For service information identified in this AD, Goodrich 
Corporation, Sensors and Integrated Systems, 100 Panton Road, 
Vergennes, Vermont 05491; phone: 802-877-4580; fax: 802-877-4444; 
email: [email protected]; Internet: http://www.goodrich.com/TechPubs.
    (3) You may review copies of the referenced service information 
at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., 
Renton, Washington. For information on the availability of this 
material at the FAA, call 425-227-1221.
    (4) You may also review copies of the service information that 
is incorporated by reference at the National Archives and Records 
Administration (NARA). For information on the availability of this 
material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

Exact source excerpt. Text positions 12915–14365, end exclusive, in the original decoded publication. SHA-256: c9764211e4720d47e1c556ba7cff364e0121231742571005dcbb7c3f78a8a450

No replacement link has been established from this edition. The complete historical rule chain and current legal effect remain unknown.

Find all recorded historical references to AD 2012-08-17 · 0 printed reference observations in this pinned collection.

These are observations from one dated publication. Current legal status is unknown; aircraft applicability, installed configuration, compliance and burden require separate evidence. Missing or unparsed conditions remain unknown.

Why these observations are shown

They were extracted offline from the same immutable official HTML source as the complete recorded text. The dated source wording, original text coordinates and exact quote digests are retained. PDF/text agreement and current regulatory effect have not been qualified.

Observation revision: whole-ad-publication-clause-observations-1.0.1. Text SHA-256: c01d0132d581aff1accf517af5e2974515056715a1c838af87f9f0fd9eab5983. Source manifest: 77f0fc3b08efc3c748def285bad7e0cc7b2f0b173f993bfd43100e39e1edefa6.

Official source · 2012-04-26

Publication text

This is the complete recorded text of this dated publication.

Current legal effect is unknown. Aircraft applicability, installed configuration and compliance require separate evidence. PDF/text agreement has not been evaluated.

Read the complete official publication text
[Federal Register Volume 77, Number 81 (Thursday, April 26, 2012)]
[Rules and Regulations]
[Pages 24831-24833]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-9713]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-0110; Directorate Identifier 2011-NM-148-AD; 
Amendment 39-17034; AD 2012-08-17]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: We are adopting a new airworthiness directive (AD) for certain 
The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 
series airplanes equipped with analog transient suppression devices 
(ATSDs) installed in accordance with Supplemental Type Certificate 
ST00146BO. This AD was prompted by multiple reports of corrosion on 
ATSDs. This AD requires revising the maintenance program to incorporate 
certain limitations. We are issuing this AD to detect and correct 
corrosion on ATSDs, which could result in the loss of high voltage 
transient protection (e.g., lightning protection) in the fuel tanks and 
consequent fuel tank explosion and loss of the airplane.

DATES: This AD is effective May 31, 2012.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in the AD as of May 31, 2012.

ADDRESSES: For service information identified in this AD, contact 
Goodrich Corporation, Sensors and Integrated Systems, 100 Panton Road, 
Vergennes, Vermont 05491; phone: 802-877-4580; fax: 802-877-4444; 
email: [email protected]; Internet: http://www.goodrich.com. You 
may review copies of the referenced service information at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, 
Washington. 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 http://www.regulations.gov; 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 Document 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: Marc Ronell, Aerospace Engineer, 
Engine and Propeller Directorate, ANE-150, FAA, New England Aircraft 
Certification Office (ACO), 12 New England Executive Park, Burlington, 
Massachusetts 01803; phone: 781-238-7776; fax: 781-238-7170; email: 
[email protected].

SUPPLEMENTARY INFORMATION: 

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to include an AD that would apply to the specified products. 
That NPRM was published in the Federal Register on February 9, 2012 (77 
FR 6692). That NPRM proposed to require revising the maintenance 
program to incorporate certain limitations.

Comments

    We gave the public the opportunity to participate in developing 
this AD. We received no comments on the NPRM (77

[[Page 24832]]

FR 6692, February 9, 2012) or on the determination of the cost to the 
public.

Changes Made to This AD

    We have redesignated Note 1 of the NPRM (77 FR 6692, February 9, 
2012) as paragraph (c)(2) of this AD and redesignated subsequent notes 
accordingly, and redesignated paragraph (c) of the NPRM as paragraph 
(c)(1) of this AD.

Conclusion

    We reviewed the relevant data and determined that air safety and 
the public interest require adopting the AD with the changes 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 (77 FR 6692, February 9, 2012) for correcting the unsafe 
condition; and
    <bullet> Do not add any additional burden upon the public than was 
already proposed in the NPRM (77 FR 6692, February 9, 2012).
    We also determined that these changes will not increase the 
economic burden on any operator or increase the scope of the AD.

Costs of Compliance

    We estimate that this AD affects 384 airplanes of U.S. registry.
    We estimate the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                    Cost per       Cost on U.S.
               Action                        Labor cost           Parts cost        product         operators
----------------------------------------------------------------------------------------------------------------
Revise maintenance program..........  1 work-hour x $85 per                $0              $85          $32,640
                                       hour = $85.
----------------------------------------------------------------------------------------------------------------

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):

2012-08-17 The Boeing Company: Amendment 39-17034; Docket No. FAA-
2012-0110; Directorate Identifier 2011-NM-148-AD.

(a) Effective Date

    This AD is effective May 31, 2012.

(b) Affected ADs

    None.

(c) Applicability

    (1) This AD applies to The Boeing Company Model 737-100, -200, -
200C, -300, -400, and -500 series airplanes, certificated in any 
category, with an original airworthiness certificate or original 
export certificate of airworthiness issued before September 26, 
2011, equipped with analog transient suppression devices (ATSDs) 
installed in accordance with Supplemental Type Certificate 
ST00146BO. http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/2399C433BB10CF1085256CCB00601A12?OpenDocument&Highlight=st00146bo
    (2) This AD requires revisions to certain operator maintenance 
documents to include new actions (e.g., inspections and/or Critical 
Design Configuration Control Limitations (CDCCLs). Compliance with 
these actions is required by 14 CFR 91.403(c). For airplanes that 
have been previously modified, altered, or repaired in the areas 
addressed by these inspections, the operator may not be able to 
accomplish the inspections described in the revisions. In this 
situation, to comply with 14 CFR 91.403(c), the operator must 
request approval for an alternative method of compliance (AMOC) 
according to paragraph (i) of this AD. The request should include a 
description of changes to the required actions that will ensure the 
continued operational safety of the airplane.

(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 2841, Fuel Quantity Indicator.

(e) Unsafe Condition

    This AD was prompted by multiple reports of corrosion on ATSDs. 
We are issuing this AD to detect and correct corrosion on ATSDs, 
which could result in the loss of high voltage transient protection 
(e.g., lightning protection) in the fuel tanks and consequent fuel 
tank explosion and loss of the airplane.

(f) Compliance

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

(g) Maintenance Program Revision

    Within 3 months after the effective date of this AD, revise the 
maintenance program to incorporate the limitations specified in 
Goodrich Principal Instructions for Continued Airworthiness Manual 
for the Analog Transient Suppression Device Installation Applicable 
to Boeing 737-100 through -500 Airplanes Supplemental Type 
Certificate--ST00146BO, Document T3044-0010-0101, Revision D, dated 
September 26, 2011. The initial compliance time for accomplishing 
each task is at the applicable

[[Page 24833]]

time specified in Goodrich Principal Instructions for Continued 
Airworthiness Manual for the Analog Transient Suppression Device 
Installation Applicable to Boeing 737-100 through -500 Airplanes 
Supplemental Type Certificate--ST00146BO, Document T3044-0010-0101, 
Revision D, dated September 26, 2011, or within 18 months after the 
effective date of this AD, whichever occurs later.

    Note 1 to paragraph (g) of this AD:  Components that have been 
identified as airworthy or installed on the affected airplanes 
before the revision of the maintenance program, as required by 
paragraph (g) of this AD, do not need to be reworked in accordance 
with the CDCCLs. However, once the maintenance program has been 
revised, paragraph (g) of this AD requires that future maintenance 
actions on these components must follow the CDCCLs.

(h) No Alternative Actions Intervals, and/or Critical Design 
Configuration Control Limitations

    After accomplishing the revision required by paragraph (g) of 
this AD, no alternative actions (e.g., inspections), intervals, and/
or CDCCLs may be used other than those specified in Goodrich 
Principal Instructions for Continued Airworthiness Manual for the 
Analog Transient Suppression Device Installation Applicable to 
Boeing 737-100 through -500 Airplanes Supplemental Type 
Certificate--ST00146BO, Document
    T3044-0010-0101, Revision D, dated September 26, 2011, unless 
the actions, intervals, and/or CDCCLs are approved as an AMOC in 
accordance with the procedures specified in paragraph (i) of this 
AD.

(i) Alternative Methods of Compliance

    (1) The Manager, Boston Aircraft Certification Office (ACO), 
FAA, has the authority to approve AMOCs for this AD, if requested 
using the procedures found in 14 CFR 39.19. In accordance with 14 
CFR 39.19, send your request to your principal inspector or local 
Flight Standards District Office, as appropriate. If sending 
information directly to the manager of the ACO, send it to the 
attention of the person identified in the Related Information 
section of this AD.
    (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.

(j) Related Information

    For more information about this AD, contact Marc Ronell, 
Aerospace Engineer, Engine and Propeller Directorate, ANE-150, FAA, 
New England Aircraft Certification Office, 12 New England Executive 
Park, Burlington, Massachusetts 01803; phone: 781-238-7776; fax: 
781-238-7170; email: [email protected].

(k) Material Incorporated by Reference

    (1) You must use the following service information to do the 
actions required by this AD, unless the AD specifies otherwise. The 
Director of the Federal Register approved the incorporation by 
reference (IBR) of the following service information under 5 U.S.C. 
552(a) and 1 CFR part 51.
    (i) Goodrich Principal Instructions for Continued Airworthiness 
Manual for the Analog Transient Suppression Device Installation 
Applicable to Boeing 737-100 through -500 Airplanes Supplemental 
Type Certificate--ST00146BO, Document T3044-0010-0101, Revision D, 
dated September 26, 2011.
    (2) For service information identified in this AD, Goodrich 
Corporation, Sensors and Integrated Systems, 100 Panton Road, 
Vergennes, Vermont 05491; phone: 802-877-4580; fax: 802-877-4444; 
email: [email protected]; Internet: http://www.goodrich.com/TechPubs.
    (3) You may review copies of the referenced service information 
at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., 
Renton, Washington. For information on the availability of this 
material at the FAA, call 425-227-1221.
    (4) You may also review copies of the service information that 
is incorporated by reference at the National Archives and Records 
Administration (NARA). For information on the availability of this 
material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Renton, Washington, on April 13, 2012.
John P. Piccola,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2012-9713 Filed 4-25-12; 8:45 am]
BILLING CODE 4910-13-P


Why this text is shown

The complete text was extracted from the official GovInfo HTML edition for this publication. Acquired 2026-10-09T03:02:47.620963+00:00. Text extraction preserves the recorded source wording; it does not determine current requirements.

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Source SHA-256
a83863db03df20ffe6758e185f13f6622c46349f176c4fb03cf55de5d5e4c26d
Text SHA-256
c01d0132d581aff1accf517af5e2974515056715a1c838af87f9f0fd9eab5983

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These are dated publication metadata, recorded clauses and literal source observations. Word, model-label, header and reference matches do not establish current legal effect, manufacturer/model identity, aircraft applicability, installed configuration or compliance.

The collection uses 33 explicit annual source snapshots. Source captures and operative-text qualifications have separate states. Missing information remains unknown.