Simulation config: frac_adsb_outage knob + retina-simulation bump

backend/core/state.py

@@ -1250,6 +1250,14 @@ def _seed_sim_fracs_from_env() -> dict:
     **_seed_sim_fracs_from_env(),
     # aircraft (commercial) fraction = 1 - sum of above
     #
+    # Transponder outages: the fraction of ADS-B-equipped aircraft the
+    # simulator takes silent mid-flight (has_adsb stays true, the broadcast
+    # stops).  Deliberately NOT part of the frac_* sum above and NOT env-seeded
+    # with them: it is a fraction OF the ADS-B population, orthogonal to the
+    # spawn-type roll, so folding it into that sum would make a scene with lots
+    # of dark traffic silently unable to test outages.  0.0 = off.
+    "frac_adsb_outage": 0.0,
+    #
     # Deliberately NO defaults for max_range_km / min_aircraft / max_aircraft:
     # the fleet orchestrator applies those keys only when present, falling back
     # to its own deployment env (FLEET_MIN_AIRCRAFT etc.).  Defaults here are a

backend/routes/output.py

@@ -137,6 +137,10 @@ async def ground_truth_aircraft():
                 "has_adsb": meta.get("has_adsb", False),
                 "adsb_callsign": meta.get("adsb_callsign"),
                 "anomaly_event": meta.get("anomaly_event"),
+                # A transponder that is silent right now (simulator outage) — the
+                # aircraft still has ADS-B (has_adsb stays true), it is just not
+                # broadcasting, which is what the known-track hold is measured on.
+                "adsb_silent": meta.get("adsb_silent", False),
                 "trail": list(trail)[-30:],
             }
         )

backend/routes/sim_ingest.py

@@ -83,6 +83,11 @@ async def push_ground_truth_snapshot(body: dict = Body(...), _key=Depends(_verif
             "speed_ms": ac.get("speed_ms", 0),
             "heading": ac.get("heading", 0),
             "has_adsb": ac.get("has_adsb", False),
+            # Transponder present but silent right now (simulator outage).
+            # has_adsb stays true, so the dark count is unaffected — this is
+            # what tells the known-track hold apart from a genuinely dark
+            # aircraft.
+            "adsb_silent": ac.get("adsb_silent", False),
             "adsb_callsign": ac.get("adsb_callsign"),
             "anomaly_event": ac.get("anomaly_event"),
         }

backend/routes/test.py

@@ -473,9 +473,22 @@ async def get_anomaly_log():
 @router.get("/api/simulation/config")
 async def get_simulation_config():
     """Return current simulation physics configuration plus live object-type counts."""
-    counts: dict[str, int] = {"anomalous": 0, "drone": 0, "aircraft": 0, "dark": 0, "total": 0}
+    counts: dict[str, int] = {
+        "anomalous": 0,
+        "drone": 0,
+        "aircraft": 0,
+        "dark": 0,
+        # Transponder-equipped aircraft currently inside an outage.  Counted
+        # alongside (not instead of) its type bucket: a silent aircraft is
+        # still a commercial aircraft, it just is not broadcasting, so this
+        # is the one count that overlaps the others.
+        "adsb_silent": 0,
+        "total": 0,
+    }
     for meta in list(state.ground_truth_meta.values()):
         counts["total"] += 1
+        if meta.get("adsb_silent"):
+            counts["adsb_silent"] += 1
         if meta.get("is_anomalous"):
             counts["anomalous"] += 1
         elif meta.get("object_type") == "drone":
@@ -498,6 +511,9 @@ async def put_simulation_config(body: dict = Body(...), _admin=Depends(require_a
 
     Accepted keys: frac_anomalous, frac_drone, frac_dark (0.0–1.0 each).
     Sum of the three must not exceed 1.0 — the remainder is commercial aircraft.
+    frac_adsb_outage (0.0–1.0) is deliberately OUTSIDE that sum: it is the
+    fraction OF the ADS-B aircraft that go transponder-silent mid-flight,
+    orthogonal to the spawn-type roll.
     Optional: max_range_km (0 = auto, or 10–400), min_aircraft (1–500),
     max_aircraft (1–500).
 
@@ -511,6 +527,7 @@ async def put_simulation_config(body: dict = Body(...), _admin=Depends(require_a
         "frac_anomalous",
         "frac_drone",
         "frac_dark",
+        "frac_adsb_outage",
         "max_range_km",
         "min_aircraft",
         "max_aircraft",
@@ -543,6 +560,7 @@ async def put_simulation_config(body: dict = Body(...), _admin=Depends(require_a
                     raise HTTPException(400, detail=f"{k} must be 0.0–1.0")
             updated[k] = v
 
+    # frac_adsb_outage is intentionally absent here — see the docstring.
     total_frac = (
         updated.get("frac_anomalous", state.simulation_config["frac_anomalous"])
         + updated.get("frac_drone", state.simulation_config["frac_drone"])

backend/services/state_snapshot.py

@@ -106,6 +106,7 @@ def save_snapshot() -> None:
         "frac_anomalous",
         "frac_drone",
         "frac_dark",
+        "frac_adsb_outage",
         "min_aircraft",
         "max_aircraft",
         "max_range_km",

backend/tests/test_sim_ingest.py

@@ -80,6 +80,25 @@ def test_old_payload_without_new_keys_defaults(self, client):
         assert meta["adsb_callsign"] is None
         assert meta["anomaly_event"] is None
 
+    def test_stores_adsb_silent_flag(self, client):
+        # Transponder outage: has_adsb stays true (the aircraft HAS one), the
+        # silent flag is what the known-track hold is verified against.
+        r = client.post(
+            "/api/test/ground-truth/push",
+            headers=_KEY,
+            json={"aircraft": [_ac(adsb_silent=True)]},
+        )
+        assert r.status_code == 200
+        meta = state.ground_truth_meta["a1b2c3"]
+        assert meta["adsb_silent"] is True
+        assert meta["has_adsb"] is True
+
+    def test_adsb_silent_defaults_false_for_older_fleets(self, client):
+        legacy = {k: v for k, v in _ac().items() if k != "adsb_silent"}
+        r = client.post("/api/test/ground-truth/push", headers=_KEY, json={"aircraft": [legacy]})
+        assert r.status_code == 200
+        assert state.ground_truth_meta["a1b2c3"]["adsb_silent"] is False
+
     def test_anomalous_push_flags_hex_and_logs_event(self, client):
         r = client.post(
             "/api/test/ground-truth/push",
@@ -170,7 +189,55 @@ def test_counts_split_out_dark_aircraft(self, client):
             }
         )
         counts = client.get("/api/simulation/config").json()["ground_truth_counts"]
-        assert counts == {"anomalous": 1, "drone": 1, "aircraft": 1, "dark": 1, "total": 4}
+        assert counts == {
+            "anomalous": 1,
+            "drone": 1,
+            "aircraft": 1,
+            "dark": 1,
+            "adsb_silent": 0,
+            "total": 4,
+        }
+
+    def test_adsb_outage_default_is_off(self, client):
+        # Default 0.0 so nothing changes for a deployment that never sets it.
+        assert client.get("/api/simulation/config").json()["frac_adsb_outage"] == 0.0
+
+    def test_adsb_outage_accepted_and_echoed(self, client):
+        r = client.put("/api/simulation/config", json={"frac_adsb_outage": 0.3})
+        assert r.status_code == 200
+        assert r.json()["config"]["frac_adsb_outage"] == 0.3
+        assert client.get("/api/simulation/config").json()["frac_adsb_outage"] == 0.3
+
+    def test_adsb_outage_out_of_range_rejected(self, client):
+        assert client.put("/api/simulation/config", json={"frac_adsb_outage": 1.5}).status_code == 400
+        assert client.put("/api/simulation/config", json={"frac_adsb_outage": -0.1}).status_code == 400
+
+    def test_adsb_outage_is_outside_the_frac_sum_constraint(self, client):
+        # It is a fraction OF the ADS-B aircraft, orthogonal to the spawn-type
+        # roll: a scene at the 1.0 type-sum ceiling must still be able to take
+        # its transponder aircraft silent.
+        r = client.put(
+            "/api/simulation/config",
+            json={"frac_anomalous": 0.1, "frac_drone": 0.1, "frac_dark": 0.8, "frac_adsb_outage": 1.0},
+        )
+        assert r.status_code == 200
+        assert r.json()["config"]["frac_adsb_outage"] == 1.0
+
+    def test_counts_report_silent_transponders_alongside_their_type(self, client):
+        # A silent aircraft is still a commercial aircraft (has_adsb stays
+        # true) — it must NOT be counted as dark, or the outage knob would be
+        # indistinguishable from frac_dark.
+        state.ground_truth_meta.update(
+            {
+                "aaa111": {"object_type": "aircraft", "has_adsb": True, "adsb_silent": True},
+                "bbb222": {"object_type": "aircraft", "has_adsb": True, "adsb_silent": False},
+                "obj-00001": {"object_type": "aircraft", "has_adsb": False},
+            }
+        )
+        counts = client.get("/api/simulation/config").json()["ground_truth_counts"]
+        assert counts["adsb_silent"] == 1
+        assert counts["aircraft"] == 2
+        assert counts["dark"] == 1
 
     def test_scene_keys_absent_by_default(self, client):
         # Only-if-set pattern (state.py): a fresh backend never ships