WAAS vs EGNOS
Scope status
This is a source-routed comparison note between WAAS and EGNOS. It compares what the knowledge base can safely say from current official/public source notes; it does not compare operational performance.
Boundary:
- It does not rank WAAS and EGNOS by accuracy, continuity, availability, coverage, maturity, or interoperability.
- It does not verify airport/runway procedure availability or approach minima.
- It does not treat FAA and EGNOS/EUSPA service documents as equivalent in detail, legal status, or service-boundary structure without direct matched extraction.
Why compare them
WAAS and EGNOS are useful comparison anchors because they represent mature U.S. and European SBAS service-provider contexts. They are also useful for showing how the KB must separate service-provider material from equipment standards, article approval, procedure design, and operational approval.
Current authenticated comparison posture
| Dimension | WAAS source-routed posture | EGNOS source-routed posture | Safe comparison rule |
|---|---|---|---|
| Dedicated source note | Source - WAAS | Source - EGNOS | Compare source posture before comparing system performance |
| Current official source basis | FAA WAAS public page and FAA August 2025 quick-facts PDF | EGNOS Safety of Life Service Definition Document page and Issue 3.6 PDF | Both have official public provider material, but not identical document types |
| Broad aviation-service claim | FAA material describes WAAS as serving all classes of aircraft in all phases of flight and supporting vertically guided approaches at qualified NAS locations | EGNOS material describes the SoL service as tailored to safety-critical aviation applications and compliant with APV-I/CAT-I requirements as defined by ICAO Annex 10 | Both can be described as aviation SBAS service-provider contexts within their source boundaries |
| Procedure-count / operational detail | FAA quick facts include LPV/LP public count snapshots for August 2025 | Current extracted EGNOS note does not provide an equivalent procedure-count snapshot | Do not compare procedure inventory until matched official procedure/AIP evidence exists |
| Authorization boundary | Aircraft/operator/runway-specific claims require FAA procedure, operational, and status sources | Official EGNOS material states operational use may require relevant-authority authorization | Keep authorization separate from service-definition statements |
What can be said safely now
- WAAS is routed through official FAA public WAAS material in Source - WAAS.
- EGNOS is routed through official EGNOS Safety of Life service-definition material in Source - EGNOS.
- Both belong to the service-provider source family routed by Source - SBAS Service Providers.
- Neither source note alone authorizes aircraft/operator use, runway-specific procedures, or comparative performance conclusions.
What remains uncertain
- Whether any interoperability statements between WAAS and EGNOS are supported by official bilateral/multilateral provider material.
- Whether procedure inventories can be compared using equivalent source types and snapshot dates.
- Whether service-area or performance comparisons can be made without mixing different definitions and legal/service commitments.
Source anchors
- Source - WAAS — official FAA public WAAS material.
- Source - EGNOS — official EGNOS Safety of Life service-definition material.
- Source - SBAS Service Providers — service-provider family router.
- SBAS Standards Source Matrix — claim-routing matrix for source-family boundaries.
Best next source-support targets
- FAA WAAS service/performance standard or performance reports.
- Official EGNOS/ESSP performance reports and current service-status material.
- FAA and European AIP/procedure sources if procedure inventories are compared.
- Official interoperability or transition-zone material before publishing cross-system interoperability conclusions.