Back to publication catalog

Published 2021-06-11 · Federal Register document 2021-12227

Airworthiness Directives; Airbus Helicopters Deutschland GmbH (AHD) Helicopters

Publication summary

The FAA is adopting a new airworthiness directive (AD) for Airbus Helicopters Deutschland GmbH (AHD) Model EC135P1, EC135P2, EC135P2+, EC135P3, EC135T1, EC135T2, EC135T2+, and EC135T3 helicopters. This AD was prompted by a report of increased control force in the collective axis. This AD requires a one-time visual inspection of the main rotor actuator (MRA), as specified in a European Aviation Safety Agency (now European Union Aviation Safety Agency) (EASA) AD, which is incorporated by reference. The FAA is issuing this AD to address the unsafe condition on these products.

Why this record is shown

Source: Federal Register annual FAA metadata. Acquired 2026-09-03T22:24:08.106391+00:00. The title, summary and date are source facts.

Source revision
federal_register_ad_metadata_2021-9c919420683447c6
Source row
results[200]
Raw source SHA-256
9c919420683447c683ad0c877cb886e341c11862be32b47c536a001b1d76dcb5

Final-rule publication

Recorded publication clauses

AD identifier printed in this edition
2021-11-17
Effective date printed in this edition
2021-07-16

Some source clauses remain unstructured. Read the complete publication for conditions that have not been interpreted here.

Read 11 complete recorded clauses
Effective Date
(a) Effective Date

    This airworthiness directive (AD) is effective July 16, 2021.

Exact source excerpt. Text positions 10697–10784, end exclusive, in the original decoded publication. SHA-256: 4af1d386f222dbcf83df794dfce02b33d9425a2edeb6f3efb08e78166bdbc746

Affected Airworthiness Directives (ADs)
(b) Affected Airworthiness Directives (ADs)

    None.

Exact source excerpt. Text positions 10784–10840, end exclusive, in the original decoded publication. SHA-256: da0b72a9b1ffff4df5a0f1441412d699333a275f4462c9dc7abcb704aa3469f3

Applicability wording · Applicability
(c) Applicability

    This AD applies to all Airbus Helicopters Deutschland GmbH (AHD) 
Model EC135P1, EC135P2, EC135P2+, EC135P3, EC135T1, EC135T2, 
EC135T2+, and EC135T3 helicopters, certificated in any category.
    Note 1 to paragraph (c): Helicopters with an EC135P3H 
designation are Model EC135P3 helicopters. Helicopters with an 
EC135T3H designation are Model EC135T3 helicopters.

Exact source excerpt. Text positions 10840–11232, end exclusive, in the original decoded publication. SHA-256: b72838508cb3294e2ec83bc1ffc13da5c465fbe927db1cf4bb9bb5c48c0e206f

Subject
(d) Subject

    Joint Aircraft System Component (JASC) Code: 6710, Main Rotor 
Control.

Exact source excerpt. Text positions 11232–11322, end exclusive, in the original decoded publication. SHA-256: bf50efae4014ecd7174b23e6bdfa884622414ad19bfa16b215837796776aae34

Reason
(e) Reason

    This AD was prompted by a report of increased control force in 
the collective axis. The FAA is issuing this AD to prevent failure 
of the main rotor actuator and subsequent loss of control of the 
helicopter.

Exact source excerpt. Text positions 11322–11549, end exclusive, in the original decoded publication. SHA-256: 97ffea719427eaf4b8050dde16d6b84efe4fe91f8bf1e05cc50849e41e742ea2

Compliance
(f) Compliance

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

Exact source excerpt. Text positions 11549–11651, end exclusive, in the original decoded publication. SHA-256: 00fbfa31932483f627d0ce0a11cbd2e35e15d9231842b91ac85623ce533912d3

Requirements
(g) Requirements

    Except as specified in paragraph (h) of this AD: Comply with all 
required actions and compliance times specified in, and in 
accordance with, European Aviation Safety Agency (now European Union 
Aviation Safety Agency) (EASA) AD 2018-0284, dated December 20, 2018 
(EASA AD 2018-0284).

Exact source excerpt. Text positions 11651–11961, end exclusive, in the original decoded publication. SHA-256: d946c8e449a3cb3db13eaeddb6a6e54cd53f02e6736458b43bd857a007c64849

Exceptions to EASA AD 2018-0284
(h) Exceptions to EASA AD 2018-0284

    (1) Where EASA AD 2018-0284 refers to its effective date, this 
AD requires using the effective date of this AD.
    (2) Where paragraph (3) of EASA AD 2018-0284 specifies 
contacting Airbus Helicopters, this AD requires performing the 
corrective action in accordance with FAA-approved procedures.
    (3) Where paragraph (4) of EASA AD 2018-0284 specifies an 
alternative method to comply with the requirements of paragraph (3) 
of EASA AD 2018-0284 by replacing an affected part, this AD requires 
removing the affected part from service as an alternative method.
    (4) Where paragraph (1) of EASA AD 2018-0284 specifies a 
compliance time of ``3 months or 50 flight hours, whichever occurs 
first,'' this AD requires a compliance time of within 50 hours time-
in-service (TIS) from the effective date of this AD.
    (5) Where paragraph (2) of EASA AD 2018-0284 specifies a 
compliance time of ``15 days,'' this AD requires using a compliance 
time of ``30 days.''
    (6) The ``Remarks'' section of EASA AD 2018-0284 does not apply 
to this AD.

Exact source excerpt. Text positions 11961–13055, end exclusive, in the original decoded publication. SHA-256: 471862a71a32857a10f0625b1963e5b7fc743d81b552d7da834ce1e4f647e129

Alternative Methods of Compliance (AMOCs)
(i) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, International Validation 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 local Flight 
Standards District Office, as appropriate. If sending information 
directly to the manager of the International Validation Branch, send 
it to the attention of the person identified in paragraph (j) of 
this AD. Information may be emailed to: [email protected].
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector,

[[Page 31089]]

or lacking a principal inspector, the manager of the local flight 
standards district office/certificate holding district office.

Exact source excerpt. Text positions 13055–13861, end exclusive, in the original decoded publication. SHA-256: 2cb07759d64b380122d47cecbdc73975d911064992f17f338b73a9fc9fca4fc6

Related Information
(j) Related Information

    For more information about this AD, contact Katherine Venegas, 
Aviation Safety Engineer, Los Angeles ACO Branch, FAA, 3960 
Paramount Blvd., Lakewood, California 90712; telephone (562) 627-
5353; email [email protected].

Exact source excerpt. Text positions 13861–14113, end exclusive, in the original decoded publication. SHA-256: 532d932a45a1b683dff4891abd46d65b43805533edcc2ca4b03939e5f0b44599

Material Incorporated by Reference
(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 this AD specifies otherwise.
    (i) European Aviation Safety Agency (EASA) AD 2018-0284, dated 
December 20, 2018.
    (ii) [Reserved]
    (3) For EASA AD 2018-0284, contact the EASA, Konrad-Adenauer-
Ufer 3, 50668 Cologne, Germany; telephone +49 221 8999 000; email 
[email protected]; Internet www.easa.europa.eu. You may find this 
EASA AD on the EASA website at https://ad.easa.europa.eu.
    (4) You may view this service information at the FAA, Office of 
the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 
6N-321, Fort Worth, TX 76177. For information on the availability of 
this material at the FAA, call (817) 222-5110. This material may be 
found in the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-
2021-0199.
    (5) You may view this material that is incorporated by reference 
at the National Archives and Records Administration (NARA). For 
information on the availability of this material at NARA, email 
[email protected], or go to https://www.archives.gov/federal-register/cfr/ibr-locations.html.

Exact source excerpt. Text positions 14113–15538, end exclusive, in the original decoded publication. SHA-256: baf72f24bf3f054a3d9aef1167d82eb1d6ccc4505b6abafce7cafd400fe825c3

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 2021-11-17 · 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: 59b6f98d785048c710728425af1683f3aaa86324d5b0d5af818d48179a3a3721. Source manifest: cfebdd70355718e2ecd3f22c5a352b9b9cfb96c7ad831ec03eea3b64dd69124f.

Official source · 2021-06-11

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 86, Number 111 (Friday, June 11, 2021)]
[Rules and Regulations]
[Pages 31087-31089]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-12227]



========================================================================
Rules and Regulations
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains regulatory documents 
having general applicability and legal effect, most of which are keyed 
to and codified in the Code of Federal Regulations, which is published 
under 50 titles pursuant to 44 U.S.C. 1510.

The Code of Federal Regulations is sold by the Superintendent of Documents. 

========================================================================


Federal Register / Vol. 86, No. 111 / Friday, June 11, 2021 / Rules 
and Regulations

[[Page 31087]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0199; Project Identifier MCAI-2021-00016-
R;Amendment 39-21579; AD 2021-11-17]
RIN 2120-AA64


Airworthiness Directives; Airbus Helicopters Deutschland GmbH 
(AHD) Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
Airbus Helicopters Deutschland GmbH (AHD) Model EC135P1, EC135P2, 
EC135P2+, EC135P3, EC135T1, EC135T2, EC135T2+, and EC135T3 helicopters. 
This AD was prompted by a report of increased control force in the 
collective axis. This AD requires a one-time visual inspection of the 
main rotor actuator (MRA), as specified in a European Aviation Safety 
Agency (now European Union Aviation Safety Agency) (EASA) AD, which is 
incorporated by reference. The FAA is issuing this AD to address the 
unsafe condition on these products.

DATES: This AD is effective July 16, 2021.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of July 16, 
2021.

ADDRESSES: For material incorporated by reference (IBR) in this AD, 
contact the EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; 
telephone +49 221 8999 000; email [email protected]; internet 
www.easa.europa.eu. You may find this material on the EASA website at 
https://ad.easa.europa.eu. You may view this material at the FAA, 
Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., 
Room 6N-321, Fort Worth, TX 76177. For information on the availability 
of this material at the FAA, call (817) 222-5110. It is also available 
in the AD docket on the internet at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0199.

Examining the AD Docket

    You may examine the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-
0199; 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.

FOR FURTHER INFORMATION CONTACT: Katherine Venegas, Aviation Safety 
Engineer, Los Angeles ACO Branch, FAA, 3960 Paramount Blvd., Lakewood, 
California 90712; telephone (562) 627-5353; email 
[email protected].

SUPPLEMENTARY INFORMATION:

Background

    EASA, which is the Technical Agent for the Member States of the 
European Union, has issued EASA AD 2018-0284, dated December 20, 2018 
(EASA AD 2018-0284), to correct an unsafe condition for Airbus 
Helicopters Deutschland GmbH (AHD) Model EC135 P1, EC135 P2, EC135 P2+, 
EC135 P3, EC135 T1, EC135 T2, EC135 T2+, EC135 T3, EC635 P2+, EC635 P3, 
EC635 T1, EC635 T2+, and EC635 T3 helicopters. Model EC635 P2+, EC635 
P3, EC635 T1, and EC635 T3 helicopters are not certificated by the FAA 
and are not included on the U.S. type certificate data sheet; this AD 
therefore does not include those helicopters in the applicability.
    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 by adding an AD that would apply to Model EC135P1, EC135P2, 
EC135P2+, EC135P3, EC135T1, EC135T2, EC135T2+, and EC135T3 helicopters. 
The NPRM published in the Federal Register on March 30, 2021 (86 FR 
16550). The NPRM was prompted by a report of increased control force in 
the collective axis on an AHD Model EC135 helicopter. Subsequent 
inspections determined that a nut on a piston of the MRA had cracked 
and separated from the piston rod. The NPRM proposed to require a one-
time visual inspection of the MRA, as specified in an EASA AD.
    The FAA is issuing this AD to prevent failure of the MRA and 
subsequent loss of control of the helicopter. See EASA AD 2018-0284 for 
additional background information.

Discussion of Final Airworthiness Directive

Comments

    The FAA gave the public the opportunity to participate in 
developing this final rule. The FAA received no comments on the NPRM or 
on the determination of the cost to the public.

Conclusion

    The FAA reviewed the relevant data and determined that air safety 
and the public interest require adopting this final rule as proposed.

Related Service Information Under 1 CFR Part 51

    EASA AD 2018-0284 describes procedures for a one-time visual 
inspection of the MRA and depending on the results, replacing the 
affected parts.
    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.

Differences Between This AD and the EASA AD

    The EASA AD requires contacting Airbus Helicopters or replacing an 
affected part, whereas this AD requires performing the corrective 
action in accordance with FAA-approved procedures or removing the 
affected parts from service instead. Where the EASA AD specifies a 
compliance time for the inspection in terms of calendar time or flight 
hours, this AD requires a compliance time in terms of hours time-in-
service instead. Where the EASA AD specifies a compliance time of 15 
days for reporting the inspection results, this AD requires that the 
findings be reported within 30 days.

Interim Action

    The FAA considers this AD interim action. If final action is later 
identified,

[[Page 31088]]

the FAA might consider further rulemaking then.

Costs of Compliance

    The FAA estimates that this AD affects 331 helicopters of U.S. 
Registry. Labor rates are estimated at $85 per work-hour. Based on 
these numbers, the FAA estimates that operators may incur the following 
costs in order to comply with this AD.
    Inspecting the nuts on the MRA pistons takes about 1 work-hour for 
an estimated cost of $85 per helicopter and $28,135 for the U.S. fleet. 
Replacing the MRA takes about 7 work-hours and parts cost $325,081 for 
an estimated cost of $325,676 per helicopter. Repairing the MRA takes 
up to about 8 work-hours and parts cost about $110 for an estimated 
cost of up to $790 per MRA. Reporting information takes about 1 hour 
for an estimated cost of $85 per helicopter and $28,135 for the U.S. 
fleet.

Paperwork Reduction Act

    A federal agency may not conduct or sponsor, and a person is not 
required to respond to, nor shall a person be subject to penalty for 
failure to comply with a collection of information subject to the 
requirements of the Paperwork Reduction Act unless that collection of 
information displays a current valid OMB control number. The control 
number for the collection of information required by this AD is 2120-
0056. The paperwork cost associated with this AD has been detailed in 
the Costs of Compliance section of this document and includes time for 
reviewing instructions, as well as completing and reviewing the 
collection of information. Therefore, all reporting associated with 
this AD is mandatory. Comments concerning the accuracy of this burden 
and suggestions for reducing the burden should be directed to 
Information Collection Clearance Officer, Federal Aviation 
Administration, 10101 Hillwood Pkwy., Fort Worth, TX 76177-1524.

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 adding the following new airworthiness 
directive:

2021-11-17 Airbus Helicopters Deutschland GmbH (AHD): Amendment 39-
21579; Docket No. FAA-2021-0199; Project Identifier MCAI-2021-00016-
R.

(a) Effective Date

    This airworthiness directive (AD) is effective July 16, 2021.

(b) Affected Airworthiness Directives (ADs)

    None.

(c) Applicability

    This AD applies to all Airbus Helicopters Deutschland GmbH (AHD) 
Model EC135P1, EC135P2, EC135P2+, EC135P3, EC135T1, EC135T2, 
EC135T2+, and EC135T3 helicopters, certificated in any category.
    Note 1 to paragraph (c): Helicopters with an EC135P3H 
designation are Model EC135P3 helicopters. Helicopters with an 
EC135T3H designation are Model EC135T3 helicopters.

(d) Subject

    Joint Aircraft System Component (JASC) Code: 6710, Main Rotor 
Control.

(e) Reason

    This AD was prompted by a report of increased control force in 
the collective axis. The FAA is issuing this AD to prevent failure 
of the main rotor actuator and subsequent loss of control of the 
helicopter.

(f) Compliance

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

(g) Requirements

    Except as specified in paragraph (h) of this AD: Comply with all 
required actions and compliance times specified in, and in 
accordance with, European Aviation Safety Agency (now European Union 
Aviation Safety Agency) (EASA) AD 2018-0284, dated December 20, 2018 
(EASA AD 2018-0284).

(h) Exceptions to EASA AD 2018-0284

    (1) Where EASA AD 2018-0284 refers to its effective date, this 
AD requires using the effective date of this AD.
    (2) Where paragraph (3) of EASA AD 2018-0284 specifies 
contacting Airbus Helicopters, this AD requires performing the 
corrective action in accordance with FAA-approved procedures.
    (3) Where paragraph (4) of EASA AD 2018-0284 specifies an 
alternative method to comply with the requirements of paragraph (3) 
of EASA AD 2018-0284 by replacing an affected part, this AD requires 
removing the affected part from service as an alternative method.
    (4) Where paragraph (1) of EASA AD 2018-0284 specifies a 
compliance time of ``3 months or 50 flight hours, whichever occurs 
first,'' this AD requires a compliance time of within 50 hours time-
in-service (TIS) from the effective date of this AD.
    (5) Where paragraph (2) of EASA AD 2018-0284 specifies a 
compliance time of ``15 days,'' this AD requires using a compliance 
time of ``30 days.''
    (6) The ``Remarks'' section of EASA AD 2018-0284 does not apply 
to this AD.

(i) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, International Validation 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 local Flight 
Standards District Office, as appropriate. If sending information 
directly to the manager of the International Validation Branch, send 
it to the attention of the person identified in paragraph (j) of 
this AD. Information may be emailed to: [email protected].
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector,

[[Page 31089]]

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 Katherine Venegas, 
Aviation Safety Engineer, Los Angeles ACO Branch, FAA, 3960 
Paramount Blvd., Lakewood, California 90712; telephone (562) 627-
5353; email [email protected].

(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 this AD specifies otherwise.
    (i) European Aviation Safety Agency (EASA) AD 2018-0284, dated 
December 20, 2018.
    (ii) [Reserved]
    (3) For EASA AD 2018-0284, contact the EASA, Konrad-Adenauer-
Ufer 3, 50668 Cologne, Germany; telephone +49 221 8999 000; email 
[email protected]; Internet www.easa.europa.eu. You may find this 
EASA AD on the EASA website at https://ad.easa.europa.eu.
    (4) You may view this service information at the FAA, Office of 
the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 
6N-321, Fort Worth, TX 76177. For information on the availability of 
this material at the FAA, call (817) 222-5110. This material may be 
found in the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-
2021-0199.
    (5) You may view this material that is incorporated by reference 
at the National Archives and Records Administration (NARA). For 
information on the availability of this material at NARA, email 
[email protected], or go to https://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on May 20, 2021.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2021-12227 Filed 6-10-21; 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 2026-10-09T01:50:43.640495+00:00. Text extraction preserves the recorded source wording; it does not determine current requirements.

Open the captured official edition

Source SHA-256
ccf4f5a51288de0b3dcfab1bb6d26501853f310682fa0bdd1d892420951edb4d
Text SHA-256
59b6f98d785048c710728425af1683f3aaa86324d5b0d5af818d48179a3a3721

Return to the full metadata catalog · Search complete publication text · Explore retained publication text and evidence

Coverage and limits

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.