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Learning path: status, sources and review scope
The single shared reference for all 48 lessons: timeline, complete source register and review scope.
Status and timeline
Editorial reference date: 11 October 2026 · German source revision R2026-10-11.5-DE-EN. This page brings together time-dependent information for all three levels. “Planned” means announced, not achieved. The date identifies the reference state of this revision; it is not a continuously updated live display.
Three kinds of status
A published specification describes a document state. A regulatory reference links documents to a legal framework. Product or project evidence shows what a specific combination actually fulfils. These three claims must remain separate.
| Date / reference | Substantiated content | Meaning for learners |
|---|---|---|
| CCS TSI 2023 | FRMCS is recognised as the successor to GSM-R; ERA lists FRMCS B0 together with ETCS B4 R1, GSM-R B1 MR1 and ATO B1 | Published reference framework, not blanket evidence of maturity [S04, S16] |
| V1 | First FRMCS specification version, reflected in the CCS TSI 2023 | Do not equate it with a complete first market-ready implementation [S04, S37] |
| December 2024 | ERA Opinion on V2 describes specification status, open points and development towards V3 | Legally non-binding opinion; no substitute for conformity assessment or a complete tendering foundation [S37] |
| April 2025 | UIC FRS, SRS and TOBA FRS 2.1.0; FFFIS 2.1.0 also published on UIC's site | Specific teaching references for this course; distinguish the V2 family from individual document versions [S04–S06, S10, S39] |
| January 2026 | ETSI TS 103 764, TS 103 765-1/-2/-3 and TS 103 792, each V1.1.1 | Architecture, transport, service, on-board and interworking foundations for this revision [S07, S08, S09, S11, S31] |
| 5 May 2026 | CCS TSI amendment through Implementing Regulation (EU) 2026/693 of 19 March 2026 enters into force | Achieved legal milestone; not an FRMCS V3 release and not automatic replacement of B0 documents with 2.1.0 [S40, S41] |
| November 2026 | V3p scheduled according to UIC's announcement of 22 April 2026 | Planned intermediate step; final MORANE-2 feedback remains relevant [S17] |
| December 2027 | ERA-aligned V3 specification set scheduled according to the same announcement | Planned target for the version termed FRMCS 1st Edition; not a claim that approval has already occurred [S17] |
| New CCS TSI 2027 | UIC names inclusion of V3 in a new CCS TSI as a planning framework | Check entry into force, transition rules and national application against actually published legal acts [S04] |
| Around 2035 | UIC expects GSM-R support to end approximately in this period | Industry planning horizon, not a globally binding shutdown date or individual supplier guarantee [S04] |
Why B0 and V1/V2/V3 are not the same numbering system
FRMCS B0 denotes a reference baseline in the TSI context. V1, V2 and V3 denote development versions of the FRMCS specifications. Individual FRS, SRS and interface documents also have their own version numbers.
B0 is not version 2.1.0. For FRMCS B0, the ERA list considered references FFFIS-7950 (index 092), FU-7120/FRS (093), AT-7800/SRS (094), FIS-7970 (095) and TOBA-7510/TOBA FRS (099), each in version 1.0.0. This course deliberately uses the newer 2.1.0 teaching editions for FRS, SRS, FFFIS and TOBA FRS. The ERA list consulted at the reference date continues to list these B0 indices at 1.0.0. This version statement relies on the ERA list; Regulation (EU) 2026/693 is identified separately as a TSI amendment. Teaching editions do not automatically replace this TSI reference baseline. [S16, S41, S05, S06, S10, S39]
A project therefore records the regulatory reference edition, supplementary technical teaching or development source, and actually agreed project baseline separately. Version 2.1.0 must not be treated as an unqualified complete tendering foundation either: Annex A of the TOBA FRS still includes a corresponding limitation. [S39]
A project consequently needs a list of the documents and applicable parts actually used. The ERA list's note that on-board specifications remain incomplete for tendering must be read alongside it. A general UIC statement about using specifications for procurement must not override this narrower qualification. [S16, S37]
Understanding 3GPP Releases
A 3GPP Release groups the development of mobile-network functions. Several releases may contain maintained specification branches. A later publication date therefore does not automatically mean a higher release number.
The course deliberately uses named editions: TS 23.501 from Release 16 for basic QoS terminology; TS 23.379 and TS 24.380 from Release 18 for the MCPTT teaching flow; and TS 33.180 from a maintained Release 16 branch for the MC security architecture. Release 17 also forms part of 5G development; which of its functions an FRMCS version needs follows from the specific references. [S13, S23–S25, S36]
These teaching sources do not form a jointly approved implementation baseline. For development and procurement, the normative references of the selected FRMCS edition must be checked in full. An equation such as “FRMCS V3 = 3GPP Release 18” is too coarse.
What MORANE-2 contributes
FP2-MORANE-2 is intended to test FRMCS V2 specifications and V3 target requirements with pre-commercial components under realistic conditions. Objectives include multi-vendor cooperation, data and voice functions, transitions and interworking. Results are intended to support further specification development. This does not replace acceptance of the specific Talbahn solution. [S35]
Maintaining this page
When a new publication appears, update date, source, status and affected lessons together. Convert planned values into achieved milestones only when supported by evidence. Then check dependent requirements, examples and references. The next factual review is due no later than publication of V3p and before use in real procurement.
Shared source register
S01 · UIC EIRENE FRS
Version: 8.1.0 · Checked: 2026-10-11
Scope: Functional requirements: voice functions, groups, priority and functional addressing.
Limitations: Teaching reference; determine applicable requirements and MI markings for the project.
Used in: 1.1, 1.2, 1.3, 1.6
S02 · UIC EIRENE SRS
Version: 16.1.0 · Checked: 2026-10-11
Scope: Section 1.4 architecture; requirements for GSM-R system functions and addressing.
Limitations: No blanket statement about every installed GSM-R implementation.
Used in: 1.3, 1.5, 1.6, 1.8
S03 · ERA: European Rail Traffic Management System
ERA: European Rail Traffic Management System
Version: Web overview · Checked: 2026-10-11
Scope: Relationship between ETCS and railway communication.
Limitations: Orientation; use S18/S30 additionally for specific ETCS statements.
Used in: 1.1, 1.2, 1.3, 1.7
S04 · UIC: FRMCS
Version: Web overview, checked 11 October 2026 · Checked: 2026-10-11
Scope: General context; FRMCS introduction situation; specifications.
Limitations: Support around 2035 is an expectation; TSI 2027 is a planning reference. Cross-check procurement claims against S16/S37.
Used in: 1.1, 1.4, 1.7, 1.9
S05 · UIC FRMCS FRS FU-7120
Version: 2.1.0, 29 April 2025 · Checked: 2026-10-11
Scope: Functional requirements, identities, Functional Alias, voice and hazard communication.
Limitations: Teaching foundation, not evidence of complete product support.
Used in: 1.2, 1.3, 1.6, 2.7, 2.8, 2.15, 2.20, 3.2
S06 · UIC FRMCS SRS AT-7800
Version: 2.1.0, 30 April 2025 · Checked: 2026-10-11
Scope: System requirements, architecture, service/transport interaction and mobility. Functional Alias: 11.6/21.3; voice profiles: 24.2.3.3 and 24.3.3.2–4; TSCTRL: 6.4.1.3.
Limitations: The project baseline must specify the applicable parts.
Used in: 1.3, 2.4, 2.7, 2.9, 2.11, 2.13, 2.15, 2.16, 2.17, 2.18, 2.19, 3.2, 3.3, 3.16
S07 · ETSI TS 103 764: FRMCS System Architecture
ETSI TS 103 764: FRMCS System Architecture
Version: 1.1.1, January 2026 · Checked: 2026-10-11
Scope: Architecture sections: FRMCS boundary, service and transport, applications using the system.
Limitations: Course diagrams are original simplifications, not normative reference drawings.
Used in: 1.3, 1.5, 1.8, 1.9, 1.10, 2.1, 2.22
S08 · ETSI TS 103 765-1: FRMCS Transport Stratum
ETSI TS 103 765-1: FRMCS Transport Stratum
Version: 1.1.1, January 2026 · Checked: 2026-10-11
Scope: Transport architecture, 5G, n100/n101 spectrum, mobility and multiple paths.
Limitations: No general end-to-end performance guarantee; QoS terminology additionally uses S13.
Used in: 1.9, 2.1, 2.3, 2.18, 3.6
S09 · ETSI TS 103 765-2: FRMCS Service Stratum
ETSI TS 103 765-2: FRMCS Service Stratum
Version: 1.1.1, January 2026 · Checked: 2026-10-11
Scope: Service architecture; SIP Core definition; registration and MC services.
Limitations: Do not equate IMS with SIP; the architecture allows the specified SIP Core alternatives.
Used in: 1.9, 2.1, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 2.10, 2.14, 2.19, 2.22, 3.5, 3.16
S10 · UIC FRMCS FFFIS FFFIS-7950
Version: 2.1.0 · Checked: 2026-10-11
Scope: 5.1/5.2 OBAPP, 5.3/5.4 TSAPP, 5.6 Tight Coupling, 5.7 Loose Coupling; 6.3/6.6/6.7 security references.
Limitations: Application interfaces, not general operating rules for control centres.
Used in: 2.1, 2.6, 2.11, 3.2, 3.3, 3.16
S11 · ETSI TS 103 792: FRMCS/GSM-R Interworking
ETSI TS 103 792: FRMCS/GSM-R Interworking
Version: 1.1.1, January 2026 · Checked: 2026-10-11
Scope: Interworking architecture and defined functional mediation.
Limitations: Demonstrate support per function and combination; not universal ETCS translation.
Used in: 1.10, 2.7, 2.20, 2.22
S12 · CEPT ECC Decision (20)02
Version: Adopted 20 November 2020; updated 10 June 2022; amended 28 June 2024 · Checked: 2026-10-11
Scope: Harmonised Railway Mobile Radio conditions and frequency ranges. The official ECC catalogue lists the amendment of 28 June 2024 (ECC#64).
Limitations: 10 June 2022 is an older edition. The official CEPT catalogue substantiates the 2024 amendment; direct PDF retrieval is restricted. Catalogue: https://docdb.cept.org/document/category/ECC_Decisions?status=ACTIVE ; newer PDF: https://docdb.cept.org/download/4521 ; older PDF: https://docdb.cept.org/download/4039 .
Used in: 2.3, 3.6
S13 · 3GPP TS 23.501, published as ETSI TS 123 501
3GPP TS 23.501, published as ETSI TS 123 501
Version: 16.14.0, September 2022 · Checked: 2026-10-11
Scope: Section 5.7: QoS Flow, 5QI, ARP, GBR and Non-GBR.
Limitations: Explicit terminology reference, not presented as the latest edition or a complete FRMCS project baseline.
Used in: 2.2, 2.3, 2.10, 2.18
S14 · CLC/TS 50701: Railway applications – Cybersecurity
CLC/TS 50701: Railway applications – Cybersecurity
Version: 2023, catalogue edition · Checked: 2026-10-11
Scope: Railway cybersecurity life cycle and relationship to RAMS.
Limitations: Catalogue and public publisher information reviewed; paid full text not reviewed completely. No clause-level conformity claimed.
Used in: 3.8
S15 · EN 50126-1: Generic RAMS process
EN 50126-1: Generic RAMS process
Version: 2017 + A1:2024, BSI edition · Checked: 2026-10-11
Scope: RAMS process framework over the life cycle.
Limitations: Catalogue and scope only; no complete review of the paid standard. Determine national adoption and project edition separately.
Used in: 1.8, 2.21, 3.8, 3.14
S16 · ERA: CCS TSI Appendix A – Mandatory specifications
ERA: CCS TSI Appendix A – Mandatory specifications
Version: ETCS B4 R1 / RMR GSM-R B1 MR1 & FRMCS B0 / ATO B1 · Checked: 2026-10-11
Scope: Reference list, especially EIRENE/ETCS entries and notes 7/9. FRMCS indices 092–095 and 099 each reference 1.0.0, not 2.1.0.
Limitations: Separate reference status from completeness and procurement readiness; the list is not itself the complete applicable law.
Used in: 1.3, 1.9, 2.11, 2.16, 2.17, 3.2, 3.15
S17 · UIC: FRMCS Mega Meeting – Aligning the next steps
UIC: FRMCS Mega Meeting – Aligning the next steps
Version: 22 April 2026 · Checked: 2026-10-11
Scope: Paragraph on V3p in November 2026 and ERA-aligned V3 set in December 2027.
Limitations: Announced targets; treated as plans, not achieved milestones, at the course reference date.
Used in: 3.2
S18 · UNISIG SUBSET-023: ERTMS/ETCS Glossary
UNISIG SUBSET-023: ERTMS/ETCS Glossary
Version: 4.0.0 · Checked: 2026-10-11
Scope: ETCS, RBC and associated terminology.
Limitations: Terminology reference, not complete ETCS system training.
Used in: 1.7, 2.16
S19 · IETF RFC 8200: Internet Protocol, Version 6
IETF RFC 8200: Internet Protocol, Version 6
Version: July 2017 · Checked: 2026-10-11
Scope: Basic principles of IP packet transmission.
Limitations: IPv6 specification as a terminology foundation; does not define a complete FRMCS IP profile.
Used in: 1.8
S20 · IETF RFC 7679: A One-Way Delay Metric
IETF RFC 7679: A One-Way Delay Metric
Version: January 2016 · Checked: 2026-10-11
Scope: Measurement boundaries, timing and treatment of observed delay.
Limitations: 150 ms in this course is a fictional budget, not a limit derived from this RFC.
Used in: 1.8, 3.7
S21 · IETF RFC 3261: SIP
Version: June 2002 · Checked: 2026-10-11
Scope: Session establishment, modification and termination.
Limitations: SIP foundations, not a complete MCPTT flow.
Used in: 2.5, 3.4
S22 · IETF RFC 3550: RTP
Version: July 2003 · Checked: 2026-10-11
Scope: Real-time media and timing information.
Limitations: RTP does not itself guarantee end-to-end quality.
Used in: 2.5
S23 · 3GPP TS 23.379 / ETSI TS 123 379: MCPTT functional architecture and information flows
3GPP TS 23.379 / ETSI TS 123 379: MCPTT functional architecture and information flows
Version: 18.13.0, July 2025 · Checked: 2026-10-11
Scope: 5.3 affiliation; 7.3/7.4 functional model; 10.6 group calls.
Limitations: The teaching flow selects an on-network variant; not a universal message sequence.
Used in: 2.6, 2.8, 3.4
S24 · 3GPP TS 24.380 / ETSI TS 124 380: MCPTT media plane control
3GPP TS 24.380 / ETSI TS 124 380: MCPTT media plane control
Version: 18.5.0, May 2024 · Checked: 2026-10-11
Scope: Floor Control procedures and Floor Request / Floor Granted messages.
Limitations: The course abstracts protocol details and covers a later speaker change.
Used in: 2.8
S25 · 3GPP TS 33.180 / ETSI TS 133 180: Security of the MC service
3GPP TS 33.180 / ETSI TS 133 180: Security of the MC service
Version: 16.13.0, February 2026 · Checked: 2026-10-11
Scope: Security architecture of Mission Critical services.
Limitations: Explicit teaching reference; cross-check newer release branches and the specific project baseline separately.
Used in: 1.8, 2.21, 3.8
S26 · IEC: Overview of the IEC 62443 series
IEC: Overview of the IEC 62443 series
Version: Public overview · Checked: 2026-10-11
Scope: Organisation and technology over the life cycle; system and component scope.
Limitations: The series has multiple parts. No blanket applicability of all parts or full-text review of all standards is claimed.
Used in: 3.8
S27 · EN 50159:2026: Safety-related communication in transmission systems
EN 50159:2026: Safety-related communication in transmission systems
Version: EN 50159:2026; EVS-EN 50159:2026 valid from 1 September 2026 · Checked: 2026-10-11
Scope: Public catalogue: published edition and scope of safety-related communication.
Limitations: Catalogue evidence, not review of the paid full text. The EVS date concerns Estonian adoption. Check national edition, transitions and project applicability separately.
Used in: 3.8
S28 · Directive (EU) 2022/2555 – NIS2
Directive (EU) 2022/2555 – NIS2
Version: 14 December 2022; official legal act · Checked: 2026-10-11
Scope: Scope and transport sector in Annex I; organisational cybersecurity duties.
Limitations: Check the specific entity and national implementation. Not an FRMCS product certificate; not automatically applicable in Switzerland.
Used in: 3.8
S29 · Swiss Federal Office of Transport: Cooperation between Switzerland and the EU
Swiss Federal Office of Transport: Cooperation between Switzerland and the EU
Version: 4 June 2025; web version checked 11 October 2026 · Checked: 2026-10-11
Scope: Land Transport Agreement, equivalence principle, Joint Committee.
Limitations: Describes the framework; no project-specific authorisation or automatic adoption of every TSI is claimed.
Used in: 3.9
S30 · ERA: Euroradio SUBSET-037-1/-2/-3
ERA: Euroradio SUBSET-037-1/-2/-3
Version: 4.0.0 in the ETCS B4 R1 reference set · Checked: 2026-10-11
Scope: Communication and coordination; supplementary parts -2 safety layer and -3 FRMCS interface: see S16.
Limitations: Distinguish this reference edition from later development versions. Not a complete ETCS safety profile.
Used in: 2.16
S31 · ETSI TS 103 765-3: On-board FRMCS
ETSI TS 103 765-3: On-board FRMCS
Version: 1.1.1, January 2026 · Checked: 2026-10-11
Scope: On-board architecture and application connection.
Limitations: Not a general control-centre operating specification; support TSAPP claims with S10.
Used in: 2.11
S32 · ERTMS/ATO Glossary
Version: Version 2, 5 July 2023 · Checked: 2026-10-11
Scope: ATO and separation of tasks in the ETCS context.
Limitations: No claim that FRMCS alone introduces ATO.
Used in: 1.7
S33 · IETF RFC 5136: Defining Network Capacity
IETF RFC 5136: Defining Network Capacity
Version: February 2008 · Checked: 2026-10-11
Scope: Capacity, data rate and comparison boundaries.
Limitations: Terminology reference, not a railway performance requirement.
Used in:
S34 · NIST SP 800-207: Zero Trust Architecture
NIST SP 800-207: Zero Trust Architecture
Version: August 2020 · Checked: 2026-10-11
Scope: Principles of explicit access verification.
Limitations: Supplementary to railway-specific foundations, not their replacement.
Used in: 3.8
S35 · Europe’s Rail: FP2-MORANE-2 – Project objectives
Europe’s Rail: FP2-MORANE-2 – Project objectives
Version: Web version checked 11 October 2026 · Checked: 2026-10-11
Scope: Validation of FRMCS V2 and V3 target requirements under realistic conditions.
Limitations: Project objective, not automatic acceptance of a Talbahn implementation.
Used in:
S36 · 3GPP: Release 17
Version: Official release overview · Checked: 2026-10-11
Scope: Context for the release branch; establish specific functions through individual TS documents.
Limitations: Catalogue entry found; direct retrieval restricted. Technical claims rely on S08/S13/S23/S24.
Used in:
S37 · ERA Opinion ERA/OPI/2024-10 on FRMCS V2
ERA Opinion ERA/OPI/2024-10 on FRMCS V2
Version: December 2024 · Checked: 2026-10-11
Scope: Sections 1, 3, 4 and 5: V2, open points and development towards V3.
Limitations: Explicitly legally non-binding opinion; not an independent conformity or tendering foundation.
Used in: 3.15
S38 · Implementing Decision (EU) 2021/1730 – RMR spectrum
Implementing Decision (EU) 2021/1730 – RMR spectrum
Version: 28 September 2021 · Checked: 2026-10-11
Scope: Harmonised frequency ranges 874.4–880 / 919.4–925 and 1900–1910 MHz.
Limitations: National spectrum rights and further conditions of use remain necessary.
Used in: 2.3
S39 · UIC TOBA-7510: On-Board FRMCS Functional Requirements Specification
UIC TOBA-7510: On-Board FRMCS Functional Requirements Specification
Version: 2.1.0, 25 April 2025 · Checked: 2026-10-11
Scope: Sections 3.3, 4 and 5: purpose, boundary and functional architecture; section 7: functional requirements; Annex A: interoperability context and tendering limitation.
Limitations: Primary TOBA teaching source. ERA index 099 for FRMCS B0 instead references 1.0.0. The informative Annex A of 2.1.0 also notes incompleteness for tendering on-board equipment.
Used in: 2.11, 3.2
S40 · ERA: Amendment to the CCS TSI Enters into Force
ERA: Amendment to the CCS TSI Enters into Force
Version: CCS TSI amendment in force since 5 May 2026 · Checked: 2026-10-11
Scope: Introduction: Implementing Regulation (EU) 2026/693 of 19 March 2026 and entry into force.
Limitations: ERA explains the act; project applicability and transitions follow from the legal text.
Used in: 3.2
S41 · Implementing Regulation (EU) 2026/693 amending the CCS TSI
Implementing Regulation (EU) 2026/693 amending the CCS TSI
Version: 19 March 2026; in force since 5 May 2026 · Checked: 2026-10-11
Scope: Amendment to Regulation (EU) 2023/1695; Appendix A FRMCS indices 092–095 and 099 remain at 1.0.0.
Limitations: Legal source; no claim of product maturity or automatic project applicability. Web retrieval may return an access-protection page; entry into force is additionally supported by S40.
Used in: 3.2
S42 · ETSI TS 103 765-4: Trackside functions and interfaces
ETSI TS 103 765-4: Trackside functions and interfaces
Version: 1.1.1 (2026-01) · Checked: 2026-10-11
Scope: Clauses 4–6: Trackside Gateway, context and procedures.
Limitations: Named teaching edition; no blanket product or project approval.
Used in: 2.1, 2.9, 2.12, 2.22, 3.3, 3.5
S43 · IETF RFC 8866: SDP
Version: 2021 · Checked: 2026-10-11
Scope: Description of media parameters.
Limitations: Named teaching edition; no blanket product or project approval.
Used in: 2.5
S44 · IETF RFC 3264: Offer/Answer
Version: 2002 · Checked: 2026-10-11
Scope: Offer and answer for media conditions.
Limitations: Named teaching edition; no blanket product or project approval.
Used in: 2.5
S45 · Kontron: Next-Gen Dispatch Management
Kontron: Next-Gen Dispatch Management
Version: Webseite / website · Checked: 2026-10-11
Scope: Evidence of the vendor label Rail Application Server.
Limitations: Vendor source: not a universal mandatory FRMCS architecture.
Used in: 2.14
S46 · 5GRAIL D5.3: Conclusion Report on Field Trials
5GRAIL D5.3: Conclusion Report on Field Trials
Version: D5.3 · Checked: 2026-10-11
Scope: Clause 4: demonstration on 20 September 2023 and limitations.
Limitations: Named teaching edition; no blanket product or project approval.
Used in: 3.11
S47 · DB: 5G-RACOM
Version: 2026 · Checked: 2026-10-11
Scope: Report on hybrid networks and multipath trials.
Limitations: Named teaching edition; no blanket product or project approval.
Used in: 2.18, 3.11
S48 · CORDIS: FP2-MORANE-2
Version: 101196125 · Checked: 2026-10-11
Scope: Project plan: laboratories and five field trials.
Limitations: Planning statements do not establish completed trials; use the central timeline for schedule information.
Used in: 3.11
S49 · 3GPP TS 23.228 / ETSI TS 123 228: IMS
3GPP TS 23.228 / ETSI TS 123 228: IMS
Version: 18.10.0 · Checked: 2026-10-11
Scope: General IMS architecture, particularly clause 4.
Limitations: Named teaching edition; no blanket product or project approval.
Used in: 2.5
S50 · 3GPP TS 23.280 / ETSI TS 123 280: Common MC architecture
3GPP TS 23.280 / ETSI TS 123 280: Common MC architecture
Version: 18.12.0 · Checked: 2026-10-11
Scope: Common MC service functions and lifecycle.
Limitations: Named teaching edition; no blanket product or project approval.
Used in: 2.6
S51 · UNISIG SUBSET-125: ERTMS/ATO SRS
UNISIG SUBSET-125: ERTMS/ATO SRS
Version: 1.1.0 · Checked: 2026-10-11
Scope: ATO system and functional relationships.
Limitations: Named teaching edition; no blanket product or project approval.
Used in: 2.17
S52 · UNISIG SUBSET-126: ATO-OB / ATO-TS application layer
UNISIG SUBSET-126: ATO-OB / ATO-TS application layer
Version: 1.1.0 · Checked: 2026-10-11
Scope: Application relationship between ATO-OB and ATO-TS.
Limitations: Named teaching edition; no blanket product or project approval.
Used in: 2.17
Review scope and limitations
This reader covers 48 lessons, both language versions and 15 teaching diagrams per language. Revision R2026-10-11.5-DE-EN addresses eight editorial findings. The affected lesson texts, tasks, model answers, diagrams and cross-references were checked, alongside automated consistency checks across all 96 language versions.
RF-01 was applied to the changed passages: a common learning focus, timely concept explanations, concrete cases, prerequisites before conclusions, connected paragraphs, unambiguous references, appropriate pacing and answerable tasks. This is an editorial self-review, not a new independent lesson-by-lesson approval of all 48 lessons. Everyday technical and IT knowledge is assumed; later levels build on earlier lessons.
The ad hoc call variant in ETSI TS 103 765-2 V1.1.1, the VAS/TSCTRL clauses in UIC SRS 2.1.0 and B0 document versions in the current ERA list were checked again. The B0 version statement is attributed to the ERA list; the corresponding EUR-Lex legal-text table could not be read directly during this follow-up check. Other source checks were retained from the previous revision; not all 52 sources were re-examined in full.
Paid standards were not checked in full. The teaching editions do not form a jointly approved product baseline. Pilot reports establish only their documented combinations and conditions; project plans do not establish completed trials. Fictional Talbahn cases are not operating instructions. Independent technical approval remains pending.
Technical checks cover language completeness, source and diagram allocation, numeric consistency, unique anchors, internal links and rendering on the website.