{
  "title": "MHD propulsion evidence bridge",
  "purpose": "Explain that HVEPS generator, NASA Ames accelerator and NASA cycle analysis are different configurations and evidence types.",
  "diagram_type": "Original hand-authored SVG explanatory schematic; no source figure artwork reproduced.",
  "not_to_scale": true,
  "panels": [
    {
      "id": "hveps-generator",
      "evidence_type": "short-duration component ground test",
      "source_urls": [
        "https://www.wpafb.af.mil/News/Article-Display/Article/401319/scramjet-mhd-system-generates-electrical-power/",
        "https://doi.org/10.2514/6.2007-3880"
      ],
      "quantity": "Test 3: 6.52 kW dissipated at load bank; not whole-engine net output",
      "does_not_establish": [
        "NASA Ames accelerator powered by HVEPS generator",
        "closed vehicle energy balance",
        "net thrust or flight"
      ]
    },
    {
      "id": "nasa-ames-accelerator",
      "evidence_type": "separate externally powered accelerator channel experiment",
      "source_urls": [
        "https://ntrs.nasa.gov/citations/20040105526"
      ],
      "quantity": "run-specific mean channel velocity increases; values are shown in the adjacent source-derived chart, not repeated here",
      "does_not_establish": [
        "generator powering accelerator",
        "closed vehicle energy balance",
        "net aircraft thrust"
      ]
    },
    {
      "id": "nasa-cycle",
      "evidence_type": "published cycle analysis/model",
      "source_urls": [
        "https://ntrs.nasa.gov/citations/20000095934"
      ],
      "quantity": "NASA/TP-2000-210387 analyzes a generic diffuser-generator-combustor-accelerator-nozzle cycle with power conditioning and a pre-ionizer; schematic intentionally simplifies the arrangement.",
      "does_not_establish": [
        "integrated hardware test",
        "flight",
        "net vehicle benefit"
      ]
    }
  ],
  "legend": {
    "orange": "hot-gas path",
    "cyan": "electrical path or external electrical connection; in the model panel it is conceptual"
  },
  "limits": [
    "All three panels depict different sources/configurations.",
    "Diagram is original, schematic, and not to scale.",
    "Do not combine their values into one measured engine performance."
  ],
  "simplifications": [
    "The NASA cycle panel omits the diffuser, power-conditioning detail and pre-ionizer drawing to keep the comparison legible; the accompanying text names these omitted stages."
  ]
}