SBAS Knowledge Base

SBAS Source Backlog

11 min read

SBAS Source Backlog

Purpose

This note tracks high-priority source notes needed before draft SBAS claims in the vault are treated as verified research conclusions.

Important boundary:

  • This is not itself an authoritative source note.
  • It is a provenance-management note built from current vault usage and public-catalog review signals.
  • External standards and guidance must still be checked against official source documents before numerical or operational requirements are published.

2026-05-02 source-matrix correction

The standards branch now has a dedicated routing page: SBAS Standards Source Matrix.

Public catalog review produced several corrections:

ReferenceCurrent disposition
Source - RTCA DO-229Keep as active GPS/SBAS airborne-equipment source-family anchor; FAA/EASA approval-source notes now split out; official-text extraction still required
Source - FAA TSO-C145e and TSO-C146eActive FAA regulator/article-approval routing note; direct TSO text extraction still required
Source - EASA ETSO-C145e and ETSO-C146eActive EASA regulator/article-approval routing note with extracted public PDF signals; official section mapping still required
Source - ICAO Doc 9849Add as active ICAO GNSS implementation-guidance anchor; direct extraction still required
Source - RTCA DO-242Red-flag as ADS-B/surveillance related; do not use for SBAS integrity or augmentation claims
Source - RTCA DO-289Red-flag as aircraft-surveillance related; do not use for SBAS performance-testing or monitoring claims
Source - ICAO Doc 9854Red-flag as Global ATM Operational Concept; do not use for SBAS performance-testing claims
Source - ICAO Doc 9855Red-flag as public-internet guidance for aeronautical applications; do not use for SBAS technical specifications

2026-05-03 core-knowledge routing update

The core SBAS layer now has a dedicated routing note: SBAS Core Claim Routing.

This update intentionally skipped new FAA-specific extraction per user instruction. Existing FAA-related source notes remain in the vault as historical/routing anchors where already present, but the current core-solidification block did not deepen FAA procedure, TSO, NFDC, or service-provider evidence.

Core concept pages should now use this ownership model:

Claim familyOwner noteEditorial boundary
SBAS definition and beginner orientationWhat is SBASHigh-level explanation only; no numerical operational requirements
ArchitectureSBAS Architecture and SBAS Architecture FlowSystem chain only; standards/service-provider details stay in source notes
Signal/message flowSBAS Signal and Message FlowFlow explanation only; no message-number or bit-field claims without Annex extraction
Correction versus integritySBAS Corrections and Integrity SeparationAccuracy-improvement claims must not be treated as safety/approval claims
Ground versus airborne responsibilitySBAS Ground Segment and Airborne Receiver ResponsibilitiesSeparate service, receiver, procedure, aircraft, and operator layers
Protection and alertingProtection Levels, Alert Limits, SBAS IntegrityExplain relationships without unsupported numerical thresholds
Service performance conceptsSBAS Service Performance ConceptsSeparate accuracy, integrity, availability, continuity, coverage, and commitments
Service volume and coverageSBAS Service Volume and CoverageCoverage is not procedure publication, aircraft eligibility, or operator approval
Approach capability labelsSBAS Approach Capability TaxonomyLP/LPV/LNAV/VNAV labels are not operational proof by themselves
Standards-to-operations escalationSBAS Standards to Operations Evidence LadderEach evidence layer must be sourced before moving upward
Receiver modes and annunciationSBAS Receiver Modes and AnnunciationNo cockpit, MOPS, timing, or pilot-action details without direct source extraction

2026-05-04 second-layer core-routing update

The second core-solidification pass added five routing notes to close remaining conceptual gaps without using long reference-website expansion:

This update intentionally keeps the new pages at concept/routing level. It does not add numerical service-performance values, message tables, alerting timing, cockpit actions, receiver algorithms, procedure minima, or state-specific operational claims.

The pass also hardened SBAS Ionospheric Threat — Empirical Evidence so empirical GNSS-RO/TEC evidence remains threat-discovery evidence rather than operational correction, GIVE, service-volume, or approval evidence.

2026-05-04 third-layer core-mechanism routing update

The third core-solidification pass added six mechanism-routing notes without long reference-website expansion:

These notes are concept/routing notes only. They do not add message numbers, bit fields, timing tolerances, correction equations, GIVE values, service-volume commitments, current outage/NOTAM data, cockpit procedures, or operational approval claims.

Mechanism ownership is now:

Mechanism claim familyOwner noteEditorial boundary
ranging / time-reference contextSBAS Ranging Sources and Time Referenceno timing tolerances, receiver approvals, or GEO-ranging claims without direct source support
orbit / clock correction contextSBAS Satellite Orbit and Clock Correctionsno equations, validity periods, update intervals, or integrity claims from correction language alone
ionospheric grid correction contextSBAS Ionospheric Grid Correction Conceptno GIVE/grid/model/certification claims from TEC research alone
correction-category languageSBAS Correction Timescale Taxonomyno message/update/degradation tables without source extraction
integrity data and user boundsSBAS Integrity Data and User Boundsno numerical bounds, alert timing, or operational approval without the applicable evidence layer
service status and noticesSBAS Service Status and Operational Noticesno stale current-status or NOTAM duplication in generic concept notes

Priority 1 — build the real standards backbone

1. ICAO Annex 10, Volume I GNSS/SBAS material

  • Current vault usage: now represented by Source - ICAO Annex 10 Volume I GNSS SBAS as a public-catalog-reviewed source-family anchor.
  • Why this matters: Annex 10, Volume I is the necessary ICAO technical/SARPs source family to investigate for many GNSS/SBAS claims.
  • Verification need: move beyond public catalog metadata by extracting the official Annex text, exact edition/amendment baseline, GNSS/SBAS sections, and downstream claim boundaries.
  • Current status: Chapter structure from public ICAO presentations added to source note (Chapter 3, Section 3.5 SBAS, Section 3.6 GBAS, Appendix B GNSS technical specifications). Direct extraction of official 8th Edition with Amendment 94 still required.
  • Current editorial rule: use the source note for routing only; do not publish detailed Annex-derived requirements until direct extraction is complete.

2. Source - RTCA DO-229

  • Current vault usage: airborne GPS/SBAS equipment, LPV-capable equipment context, integrity/protection/alert-limit pages, aviation MOC.
  • Why this matters: it is currently the strongest public-product-and-regulatory-signal-reviewed source-family anchor for GPS/SBAS airborne equipment.
  • Verification need: direct extraction of official revision-specific equipment classes, intended functions, alerting/integrity language, test methods, exclusions, and the relationship between DO-229F, DO-229E, Source - FAA TSO-C145e and TSO-C146e, and Source - EASA ETSO-C145e and ETSO-C146e.
  • Current editorial rule: use DO-229 for receiver/equipment routing only; do not infer installation approval, operational approval, procedure minima, service status, or DFMC requirements.
  • Current status: Chapter/section structure added to source note (Section 1 general requirements, Section 2 Class Beta/Gamma/Delta equipment standards, avionics Class 1–4 capability table, DFMC boundary, PRN code expansion context, ICAO Annex 10 cross-reference). Direct extraction of official RTCA DO-229F text still required.

3. FAA/EASA TSO/ETSO approval-source notes

  • Current vault usage: now represented by Source - FAA TSO-C145e and TSO-C146e and Source - EASA ETSO-C145e and ETSO-C146e.
  • Why this matters: DO-229 equipment-MOPS statements must be separated from jurisdiction-specific article approval, installation approval, and operational approval.
  • Verification need: direct FAA TSO-C145e/C146e extraction and deeper EASA section-level mapping before publishing class-specific approval claims.
  • Current editorial rule: use these notes for article-approval routing only; do not infer aircraft installation, operational use, procedure availability, or regulator equivalence.

4. Source - ICAO Doc 9849

  • Current vault usage: newly added GNSS implementation-guidance anchor.
  • Why this matters: it appears to be the appropriate ICAO manual for state GNSS implementation context, replacing several earlier mis-scoped draft references.
  • Verification need: direct extraction of SBAS implementation, monitoring/assessment/reporting, DFMC GNSS, RFI mitigation, and Annex 10 relationship language.
  • Current status: Chapter structure added from 5 public ICAO sources (Chapter 1–7 from 2nd Ed.; confirmed/revised for 4th Ed./5th Ed.; Chapter 5 GNSS Vulnerability confirmed in 5th Ed.; S1–S7 spoofing classification confirmed; GALILEO/BDS confirmed operational in 4th Ed. Chapter 3). Direct extraction of official 5th Edition text still required.

5. Procedure-design and PBN source family

  • Current vault usage: LPV, LNAV/VNAV, RNAV, RNP, and GBAS procedure notes now link to Source - ICAO PANS-OPS Doc 8168 and Doc 9613 PBN Manual and Source - FAA and EASA Procedure-Design and PBN Material.
  • Why this matters: procedure design is now represented by dedicated source notes separating it from equipment MOPS, article approval, and service-provider commitment.
  • Verification need: direct extraction of Doc 8168 Vol II (procedure-design criteria), Doc 9613 (RNP navigation specifications), FAA Order 8260.3G/8260.58D (U.S. TERPS/PBN criteria), and EASA AMC/GM (European PBN operational approval).
  • Current editorial rule: use these notes for procedure-design routing only; do not infer procedure minima, obstacle-clearance values, or airport/runway eligibility without official text extraction.

6. Service-provider source family

  • Current vault usage: WAAS, EGNOS, MSAS, GAGAN, BDSBAS, KASS, SouthPAN, and SDCM regional system pages now link to Source - SBAS Service Providers. Dedicated child source notes now exist for Source - WAAS, Source - EGNOS, Source - GAGAN SBAS Operation, Source - MSAS, Source - BDSBAS, Source - KASS, Source - SouthPAN, and Source - SDCM. Use SBAS Operational Validation Dashboard before upgrading any service-provider evidence into operational aviation claims.
  • Why this matters: service commitments, coverage, availability, and system status are provider-specific.
  • Verification need: continue deeper official service-provider/regulator/AIP extraction before publishing comparative tables, service-volume boundaries, procedure availability, or operational-approval claims.
  • Current status: Partial direct extraction completed for WAAS (FAA WAAS page + August 2025 quick facts), EGNOS (official SoL SDD page + Issue 3.6 PDF), GAGAN (ICAO APAC ITF/7 IP05b + AAI GEO FAQ), MSAS (QZSS service page + ICAO APAC CNS SG/24 IP15), SouthPAN (official FAQ, early Open Services factsheet, Signal-In-Space service definition), BDSBAS (official BDSBAS-B1C ICD + bounded technical-public context), KASS (KARI official page + ICAO APAC ITF/5 IP/09 + bounded contractor-public certification signal), and SDCM (GLONASS IAC / OS PS source posture plus historical ICAO development-context evidence).
  • Current editorial rule: use Source - SBAS Service Providers for service-provider routing; use dedicated child source notes only within their stated boundaries; do not infer comparative performance, availability percentages, interoperability, operational approval, or procedure minima without official service-provider/regulator/AIP extraction.

7. Core SBAS concept routing

Priority 2 — regional and European framework references

  • EUROCAE ED references remain candidates but need exact title/scope verification before being used for EGNOS/SBAS claims.
  • APAC, APANPIRG, CNS SG, AIP/AIS, regulator, and ANSP source notes remain important for ASEAN implementation analysis.
  • Country-specific readiness claims should continue to use cautious evidence categories unless direct institutional sources support stronger statements.

Claim clusters that still need direct source support

Standards mapping

  • document titles and editions;
  • document scope statements;
  • whether a source is airborne-equipment, system-level, procedure-design, service-provider, regulator/ANSP, or implementation guidance;
  • whether source material is normative, guidance, catalog metadata, or secondary commentary.

Performance figures

  • horizontal/vertical accuracy numbers;
  • continuity and availability percentages;
  • alerting or time-to-alert values;
  • regional uptime and service-performance figures.

Operational claims

  • LPV/APV capability statements;
  • aircraft/equipment eligibility;
  • regional operational approval statements;
  • procedure availability;
  • interoperability claims across WAAS/EGNOS/MSAS/GAGAN and other systems.

Suggested execution order

  1. Directly extract Source - ICAO Annex 10 Volume I GNSS SBAS from the official Annex text and classify GNSS/SBAS claims by section and amendment baseline.
  2. Directly extract the official Source - RTCA DO-229 text and deepen non-FAA article-approval routing where needed; direct FAA extraction and long reference-website expansion are skipped in the current core-solidification scope.
  3. Directly extract Source - ICAO Doc 9849.
  4. Build procedure-design/PBN source notes. Completed 2026-05-03: Source - ICAO PANS-OPS Doc 8168 and Doc 9613 PBN Manual and Source - FAA and EASA Procedure-Design and PBN Material now exist as routing anchors; direct text extraction still required.
  5. Build service-provider source notes for major SBAS systems. Substantially completed 2026-05-03 for the current major-system set: Source - SBAS Service Providers exists as the family routing anchor; direct child-source extraction/source-posture notes now exist for Source - WAAS, Source - EGNOS, Source - GAGAN SBAS Operation, Source - MSAS, Source - BDSBAS, Source - KASS, Source - SouthPAN, and Source - SDCM. Remaining work is deeper service-provider/regulator/AIP extraction, not first-layer child-source creation. Use SBAS Operational Validation Dashboard to prevent child source notes from being misused as operational approval evidence.
  6. Use SBAS Core Claim Routing before editing core concept pages; keep architecture, signal/message flow, correction/integrity separation, ground/airborne responsibility, protection-level, and alert-limit claims atomic and non-overlapping.
  7. Revisit SBAS Integrity, Protection Levels, Alert Limits, and procedure pages with numerical values only after the above source anchors are directly extracted.
  8. Continue ASEAN/regional source hardening through ASEAN SBAS Source Backlog.

Graph View

Backlinks