Map: pin 511NY camera feeds as tiles on the map (#183)

Clicking a camera's snapshot pins a 192x108 tile anchored at the camera --
the live HLS stream when the camera has one (hls.js; Safari native), else the
snapshot refreshed every 60s, falling back to the snapshot if the stream dies.
Up to 6 pins, oldest dropped. Players exist only while the DOT Cameras overlay
is on, so hiding it stops every stream.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

drb-c2-core/.env.example

@@ -26,6 +26,7 @@ NODE_OFFLINE_THRESHOLD=90
 # Google Maps — for geocoding location strings extracted from transcripts
 # Enable "Geocoding API" in Cloud Console for this key
 GOOGLE_MAPS_API_KEY=
+NY511_API_KEY=
 
 # OpenAI — for transcription (Whisper), intelligence extraction, embeddings, and summaries
 OPENAI_API_KEY=

drb-c2-core/app/config.py

@@ -32,6 +32,9 @@ class Settings(BaseSettings):
 
     # Google Maps (geocoding)
     google_maps_api_key: Optional[str] = None
+    # 511NY developer key (server-26#183). Optional: the API answered without one
+    # as of 2026-09-27, but its terms require a registered key.
+    ny511_api_key: Optional[str] = None
 
     # Gemini (intelligence extraction, embeddings, incident summaries)
     gemini_api_key: Optional[str] = None

drb-c2-core/app/internal/mqtt_handler.py

@@ -112,7 +112,9 @@ class MQTTHandler:
                 "approval_status": "pending",
                 "node_type": payload.get("node_type", "fixed"),
                 "secondary_sdr_mode": payload.get("secondary_sdr_mode", "none"),
-                "sdr_count": payload.get("sdr_count", 1),
+                "secondary_sdr_priority": payload.get("secondary_sdr_priority", []),
+                "secondary_sdr_running": payload.get("secondary_sdr_running"),
+                "sdr_count": payload.get("sdr_count"),  # None until reported, never a guessed 1
                 "enforce_override_timeout": payload.get("enforce_override_timeout", True),
                 "is_overridden": False,
                 "override_system_id": None,
@@ -143,8 +145,9 @@ class MQTTHandler:
             updates["node_type"] = node_type
             updates["enforce_override_timeout"] = enforce_timeout
 
-            if "secondary_sdr_mode" in payload:
-                updates["secondary_sdr_mode"] = payload["secondary_sdr_mode"]
+            for key in ("secondary_sdr_mode", "secondary_sdr_priority", "secondary_sdr_running"):
+                if key in payload:
+                    updates[key] = payload[key]
             if "sdr_count" in payload:
                 updates["sdr_count"] = payload["sdr_count"]
 

drb-c2-core/app/internal/ny511.py

@@ -0,0 +1,140 @@
+"""511NY (NYSDOT) traffic cameras and events, cached in memory (server-26#183).
+
+Public data, identical for every org, so it is NOT written to Firestore: the
+statewide feeds are ~3k cameras and ~2.3k events, and re-writing them every
+poll would be millions of writes a day for data nobody needs history of. The
+cache is filled lazily on request and refreshed per TTL, so an idle deploy
+makes no 511 calls at all.
+
+A failed refresh keeps serving the last good data and reports the error and
+its age to the caller -- an empty layer must never be the only symptom of a
+dead feed (the AI-silent-failures lesson).
+"""
+import asyncio
+import time
+from datetime import datetime
+from typing import Any, Dict, List, Optional
+
+import httpx
+
+from app.config import settings
+from app.internal.logger import logger
+
+_BASE = "https://511ny.org/api"
+CAMERAS_TTL_S = 60 * 60   # camera list is near-static
+EVENTS_TTL_S = 2 * 60     # accidents/closures change minute to minute
+RETRY_AFTER_FAILURE_S = 60
+_DESCRIPTION_MAX = 500
+
+
+class _Feed:
+    def __init__(self, path: str, ttl_s: int, normalize):
+        self.path = path
+        self.ttl_s = ttl_s
+        self.normalize = normalize
+        self.items: List[Dict[str, Any]] = []
+        self.fetched_at: Optional[float] = None   # epoch s of last SUCCESSFUL fetch
+        self.error: Optional[str] = None
+        self._next_attempt = 0.0
+        self._lock = asyncio.Lock()
+
+    async def get(self) -> "_Feed":
+        if time.time() < self._next_attempt:
+            return self
+        async with self._lock:
+            if time.time() < self._next_attempt:
+                return self   # another request refreshed while we waited
+            try:
+                self.items = await _fetch(self.path, self.normalize)
+                self.fetched_at = time.time()
+                self.error = None
+                self._next_attempt = time.time() + self.ttl_s
+            except Exception as e:
+                self._next_attempt = time.time() + min(self.ttl_s, RETRY_AFTER_FAILURE_S)
+                self.error = f"{type(e).__name__}: {e}"[:300]
+                logger.warning(f"511NY {self.path} refresh failed, serving {len(self.items)} cached: {self.error}")
+        return self
+
+
+async def _fetch(path: str, normalize) -> List[Dict[str, Any]]:
+    params = {"format": "json"}
+    if settings.ny511_api_key:
+        params["key"] = settings.ny511_api_key
+    async with httpx.AsyncClient(timeout=20.0) as client:
+        r = await client.get(f"{_BASE}/{path}", params=params)
+        r.raise_for_status()
+        raw = r.json()
+    if not isinstance(raw, list):
+        raise ValueError(f"expected a JSON list, got {type(raw).__name__}")
+    out = [n for n in (normalize(x) for x in raw) if n is not None]
+    if raw and not out:
+        # every record failed to normalize: the schema changed under us
+        raise ValueError(f"0 of {len(raw)} records parsed -- 511NY schema change?")
+    return out
+
+
+def _coords(x: Dict[str, Any]) -> Optional[tuple]:
+    try:
+        lat, lon = float(x["Latitude"]), float(x["Longitude"])
+    except (KeyError, TypeError, ValueError):
+        return None
+    if lat == 0 and lon == 0:
+        return None
+    return lat, lon
+
+
+def _local_iso(s: Any) -> Optional[str]:
+    """511NY stamps are 'DD/MM/YYYY HH:MM:SS' New York local time. Returned as a
+    naive ISO string (no offset) -- display-only, never compared to UTC."""
+    if not s:
+        return None
+    try:
+        return datetime.strptime(s, "%d/%m/%Y %H:%M:%S").isoformat()
+    except (TypeError, ValueError):
+        return None
+
+
+def normalize_camera(x: Dict[str, Any]) -> Optional[Dict[str, Any]]:
+    c = _coords(x)
+    if c is None or x.get("Disabled") or x.get("Blocked") or not x.get("ID"):
+        return None
+    return {
+        "id": x["ID"],
+        "lat": c[0],
+        "lon": c[1],
+        "name": x.get("Name") or "",
+        "roadway": x.get("RoadwayName") or "",
+        "direction": x.get("DirectionOfTravel") or "",
+        "image_url": x.get("Url"),      # 511NY serves the current still at this URL
+        "video_url": x.get("VideoUrl"),  # HLS playlist, when the camera streams
+    }
+
+
+def normalize_event(x: Dict[str, Any]) -> Optional[Dict[str, Any]]:
+    c = _coords(x)
+    if c is None or not x.get("ID"):
+        return None
+    desc = x.get("Description") or ""
+    return {
+        "id": x["ID"],
+        "lat": c[0],
+        "lon": c[1],
+        "type": x.get("EventType") or "",
+        "subtype": x.get("EventSubType") or "",
+        "severity": x.get("Severity") or "",
+        "roadway": x.get("RoadwayName") or "",
+        "direction": x.get("DirectionOfTravel") or "",
+        "county": x.get("CountyName") or "",
+        "description": desc[:_DESCRIPTION_MAX] + ("…" if len(desc) > _DESCRIPTION_MAX else ""),
+        "start_local": _local_iso(x.get("StartDate")),
+        "planned_end_local": _local_iso(x.get("PlannedEndDate")),
+        "updated_local": _local_iso(x.get("LastUpdated")),
+    }
+
+
+cameras = _Feed("getcameras", CAMERAS_TTL_S, normalize_camera)
+events = _Feed("getevents", EVENTS_TTL_S, normalize_event)
+
+
+def in_bbox(items: List[Dict[str, Any]], south: float, west: float, north: float, east: float) -> List[Dict[str, Any]]:
+    return [i for i in items if south <= i["lat"] <= north and west <= i["lon"] <= east]

drb-c2-core/app/main.py

@@ -17,7 +17,7 @@ from app.internal.auth import (
     require_node_service_or_firebase_token,
 )
 from app.routers import nodes, systems, calls, upload, tokens, incidents, alerts, admin, trips, places, links, users
-from app.routers import enrollment, media, org, waitlist, telemetry, replay
+from app.routers import enrollment, media, org, waitlist, telemetry, replay, traffic
 from app.internal import dynsec
 from app.internal import firestore as fstore
 
@@ -127,6 +127,7 @@ app.include_router(incidents.router, dependencies=[Depends(require_service_or_fi
 app.include_router(alerts.router,    dependencies=[Depends(require_service_or_firebase_token)])
 app.include_router(trips.router,     dependencies=[Depends(require_service_or_firebase_token)])
 app.include_router(places.router,    dependencies=[Depends(require_service_or_firebase_token)])
+app.include_router(traffic.router,   dependencies=[Depends(require_service_or_firebase_token)])
 app.include_router(upload.router)    # auth is per-node, handled inline
 app.include_router(admin.router)     # auth is per-endpoint (read: firebase, write: admin)
 app.include_router(replay.router)    # auth: admin only (every route spends or reads a replay run)

drb-c2-core/app/models.py

@@ -62,8 +62,13 @@ class NodeRecord(BaseModel):
     last_seen: Optional[datetime] = None
     assigned_system_id: Optional[str] = None
     node_type: str = "fixed"  # fixed or portable
-    secondary_sdr_mode: str = "none"  # none | adsb | ais | op25_2 — requires a second physical SDR
-    sdr_count: int = 1  # self-reported by the node's checkin, best-effort
+    secondary_sdr_mode: str = "none"  # legacy single-mode field; priority[0] on current nodes
+    # Ordered decoders for the SDRs beyond op25's (node-26#9): the node runs
+    # them top-down until it runs out of dongles. Mirrored from the node's own
+    # checkin, which is the source of truth; set via PATCH /nodes/{id}.
+    secondary_sdr_priority: List[str] = []
+    secondary_sdr_running: Optional[List[str]] = None  # what the node reports actually running
+    sdr_count: Optional[int] = None  # self-reported by the node's checkin; None = never reported
     enforce_override_timeout: bool = True
     is_overridden: bool = False
     override_system_id: Optional[str] = None

drb-c2-core/app/routers/nodes.py

@@ -1,5 +1,5 @@
 import secrets
-from typing import Optional
+from typing import List, Optional
 from fastapi import APIRouter, HTTPException, Depends, Query
 from pydantic import BaseModel
 from app.models import CommandPayload
@@ -192,10 +192,15 @@ async def assign_system(
     return {"ok": True}
 
 
+SECONDARY_SDR_MODES = ("adsb", "ais")
+
+
 class NodeUpdateBody(BaseModel):
     node_type: Optional[str] = None
     enforce_override_timeout: Optional[bool] = None
-    secondary_sdr_mode: Optional[str] = None  # none | adsb | ais | op25_2
+    secondary_sdr_mode: Optional[str] = None  # legacy: none | adsb | ais
+    # Ordered, e.g. ["adsb", "ais"]: SDRs beyond op25's run these top-down.
+    secondary_sdr_priority: Optional[List[str]] = None
 
 
 @router.patch("/{node_id}")
@@ -212,8 +217,23 @@ async def update_node(
     if not updates:
         return {"ok": True}
 
+    priority = updates.get("secondary_sdr_priority")
+    if priority is not None:
+        unknown = [m for m in priority if m not in SECONDARY_SDR_MODES]
+        if unknown or len(set(priority)) != len(priority):
+            raise HTTPException(400, f"secondary_sdr_priority must be distinct values from {SECONDARY_SDR_MODES}.")
+        updates["secondary_sdr_mode"] = priority[0] if priority else "none"
+
     await fstore.doc_update("nodes", node_id, updates)
 
+    # Priority goes as its own command: a config re-push restarts OP25, and
+    # changing what the spare dongles do must never interrupt P25 recording.
+    # The node applies it, then its checkin reports back what's really running.
+    if priority is not None:
+        mqtt_handler.send_command(node_id, {"action": "set_secondary_priority", "priority": priority})
+        if set(updates) <= {"secondary_sdr_priority", "secondary_sdr_mode"}:
+            return {"ok": True}
+
     # Re-push config to apply new node settings locally
     updated_node = await fstore.doc_get("nodes", node_id)
     assigned_system_id = updated_node.get("assigned_system_id")
@@ -228,7 +248,9 @@ async def update_node(
             }
             if updated_node.get("ppm_override") is not None:
                 push_payload["ppm_override"] = updated_node["ppm_override"]
-            if updated_node.get("secondary_sdr_mode") is not None:
+            if updated_node.get("secondary_sdr_priority") is not None:
+                push_payload["secondary_sdr_priority"] = updated_node["secondary_sdr_priority"]
+            elif updated_node.get("secondary_sdr_mode") is not None:
                 push_payload["secondary_sdr_mode"] = updated_node["secondary_sdr_mode"]
             mqtt_handler.push_config(node_id, push_payload)
 

drb-c2-core/app/routers/telemetry.py

@@ -1,5 +1,6 @@
-from datetime import datetime, timezone
-from typing import List, Optional
+import asyncio
+from datetime import datetime, timedelta, timezone
+from typing import Dict, List, Optional, Tuple
 
 from fastapi import APIRouter, Depends, HTTPException
 from pydantic import BaseModel
@@ -10,6 +11,20 @@ from app.internal.logger import logger
 
 router = APIRouter(prefix="/telemetry", tags=["telemetry"])
 
+# Flight trail: every position change is also written to
+# aircraft/{icao}/positions/{epoch_ms}, so clicking an aircraft on the map can
+# draw the path heard so far. Points expire via a Firestore TTL policy on
+# expire_at (infra/firestore/firestore.indexes.json fieldOverrides).
+POSITIONS_SUBCOLLECTION = "positions"
+POSITION_TTL = timedelta(hours=24)
+
+# Last position written per icao, so an aircraft reported unchanged across
+# several 10s uploads (readsb holds a position until a new one decodes)
+# doesn't get a duplicate point each time. Process-local and lossy by design:
+# after a restart the worst case is one duplicate point per aircraft.
+_last_position: Dict[str, Tuple[float, float]] = {}
+_LAST_POSITION_MAX = 5000
+
 
 class AircraftReport(BaseModel):
     icao: str
@@ -32,8 +47,8 @@ async def upload_adsb(
 ):
     """
     Node-initiated: a second-SDR ADS-B decoder (node-26#9) periodically posts
-    its current aircraft snapshot here. One doc per icao, last-seen-wins —
-    this is a live-map overlay, not a flight history.
+    its current aircraft snapshot here. One doc per icao, last-seen-wins,
+    plus one trail point per position change (see POSITIONS_SUBCOLLECTION).
     """
     node_id = decoded.get("node_id")
     if not node_id:
@@ -43,7 +58,11 @@ async def upload_adsb(
     org_id = node.get("org_id") if node else None
     now = datetime.now(timezone.utc).isoformat()
 
+    expire_at = datetime.now(timezone.utc) + POSITION_TTL
+    epoch_ms = int(datetime.now(timezone.utc).timestamp() * 1000)
+
     writes = []
+    trail = []
     for ac in body.aircraft:
         if not ac.icao:
             continue
@@ -62,12 +81,33 @@ async def upload_adsb(
             doc["org_id"] = org_id
         writes.append(("aircraft", ac.icao, doc))
 
-    for collection, doc_id, doc in writes:
+        if ac.lat is None or ac.lon is None:
+            continue
+        pos = (ac.lat, ac.lon)
+        if _last_position.get(ac.icao) == pos:
+            continue
+        _last_position[ac.icao] = pos
+        point = {
+            "lat": ac.lat,
+            "lon": ac.lon,
+            "altitude_ft": ac.altitude_ft,
+            "t": now,
+            "expire_at": expire_at,
+        }
+        trail.append((f"aircraft/{ac.icao}/{POSITIONS_SUBCOLLECTION}", str(epoch_ms), point))
+
+    if len(_last_position) > _LAST_POSITION_MAX:
+        _last_position.clear()
+
+    async def _write(collection: str, doc_id: str, doc: dict) -> None:
         try:
             await fstore.doc_set(collection, doc_id, doc, merge=True)
         except Exception as e:
             logger.warning(f"Failed to upsert {collection}/{doc_id} from node {node_id}: {e}")
 
+    # Concurrent: a busy sky is dozens of aircraft, two writes each, every 10s.
+    await asyncio.gather(*(_write(*w) for w in writes + trail))
+
     return {"ok": True, "count": len(writes)}
 
 

drb-c2-core/app/routers/traffic.py

@@ -0,0 +1,38 @@
+import asyncio
+from typing import Optional
+
+from fastapi import APIRouter, HTTPException, Query
+
+from app.internal import ny511
+
+router = APIRouter(prefix="/traffic", tags=["traffic"])
+
+# Per-layer cap per response. A statewide view is ~3k cameras; past this the
+# map is unreadable anyway, and the client is told the list was cut.
+MAX_ITEMS = 1500
+
+
+def _feed_status(feed: "ny511._Feed") -> dict:
+    return {"fetched_at": feed.fetched_at, "error": feed.error}
+
+
+@router.get("/511")
+async def get_511(
+    south: float = Query(..., ge=-90, le=90),
+    west: float = Query(..., ge=-180, le=180),
+    north: float = Query(..., ge=-90, le=90),
+    east: float = Query(..., ge=-180, le=180),
+    layers: Optional[str] = Query("cameras,events", description="comma list: cameras, events"),
+):
+    if south > north or west > east:
+        raise HTTPException(400, "bbox must satisfy south<=north and west<=east")
+    wanted = {s.strip() for s in (layers or "").split(",") if s.strip()}
+    feeds = {name: getattr(ny511, name) for name in ("cameras", "events") if name in wanted}
+    await asyncio.gather(*(f.get() for f in feeds.values()))
+
+    out: dict = {}
+    for name, feed in feeds.items():
+        hits = ny511.in_bbox(feed.items, south, west, north, east)
+        out[name] = hits[:MAX_ITEMS]
+        out[f"{name}_status"] = {**_feed_status(feed), "total_in_bbox": len(hits), "truncated": len(hits) > MAX_ITEMS}
+    return out

drb-c2-core/tests/test_node_secondary_priority.py

@@ -0,0 +1,59 @@
+"""
+node-26#9 — PATCH /nodes/{id} secondary_sdr_priority.
+
+The priority must reach the node as its own MQTT command, never via a config
+re-push: a config push restarts OP25, and reordering what the spare dongles do
+must not interrupt P25 recording.
+"""
+from unittest.mock import AsyncMock, MagicMock, patch
+
+from fastapi.testclient import TestClient
+
+from app.main import app
+from app.internal.auth import require_admin_token, require_service_or_firebase_token
+from app.routers import nodes
+
+client = TestClient(app)
+
+NODE = {"node_id": "n1", "assigned_system_id": "sys-1", "hardware_preset": "rtl-sdr-v3"}
+
+
+def setup_function():
+    app.dependency_overrides[require_admin_token] = lambda: {"admin": True}
+    app.dependency_overrides[require_service_or_firebase_token] = lambda: {"admin": True}
+
+
+def teardown_function():
+    app.dependency_overrides.pop(require_admin_token, None)
+    app.dependency_overrides.pop(require_service_or_firebase_token, None)
+
+
+def _patch(body):
+    with patch.object(nodes.fstore, "doc_get", AsyncMock(side_effect=lambda c, i: NODE if c == "nodes" else {"system_id": "sys-1"})), \
+         patch.object(nodes.fstore, "doc_update", AsyncMock()) as update, \
+         patch.object(nodes.mqtt_handler, "send_command", MagicMock(return_value=True)) as command, \
+         patch.object(nodes.mqtt_handler, "push_config", MagicMock()) as push:
+        resp = client.patch("/nodes/n1", json=body)
+    return resp, update, command, push
+
+
+def test_priority_only_sends_command_and_never_repushes_config():
+    resp, update, command, push = _patch({"secondary_sdr_priority": ["ais", "adsb"]})
+    assert resp.status_code == 200
+    command.assert_called_once_with("n1", {"action": "set_secondary_priority", "priority": ["ais", "adsb"]})
+    push.assert_not_called()
+    (_, _, updates), _ = update.await_args
+    assert updates == {"secondary_sdr_priority": ["ais", "adsb"], "secondary_sdr_mode": "ais"}
+
+
+def test_empty_priority_turns_secondaries_off():
+    resp, update, command, push = _patch({"secondary_sdr_priority": []})
+    assert resp.status_code == 200
+    command.assert_called_once_with("n1", {"action": "set_secondary_priority", "priority": []})
+    (_, _, updates), _ = update.await_args
+    assert updates["secondary_sdr_mode"] == "none"
+
+
+def test_unknown_or_duplicate_modes_are_rejected():
+    assert _patch({"secondary_sdr_priority": ["adsb", "sonar"]})[0].status_code == 400
+    assert _patch({"secondary_sdr_priority": ["adsb", "adsb"]})[0].status_code == 400

drb-c2-core/tests/test_ny511.py

@@ -0,0 +1,98 @@
+"""
+server-26#183 — 511NY cameras/events layer.
+
+The feed is scraped from a third party, so the tests pin the two failure shapes
+that would otherwise look like "no traffic right now": a refresh error must keep
+the last good data AND report the error, and a schema change (every record
+unparseable) must be an error, not an empty list.
+"""
+import asyncio
+from unittest.mock import AsyncMock, patch
+
+from fastapi.testclient import TestClient
+
+from app.main import app
+from app.internal import ny511
+from app.internal.auth import require_service_or_firebase_token
+
+client = TestClient(app)
+
+CAM = {"Latitude": 41.03, "Longitude": -73.76, "ID": "NYSDOT-1", "Name": "I-287 at Exit 5",
+       "DirectionOfTravel": "Unknown", "RoadwayName": "I-287", "Url": "https://511ny.org/map/Cctv/1",
+       "VideoUrl": None, "Disabled": False, "Blocked": False}
+EVENT = {"Latitude": 41.019265, "Longitude": -73.797869, "ID": "TRANSCOM-1", "EventType": "roadwork",
+         "EventSubType": "Gas main repairs", "Severity": "Unknown", "RoadwayName": "NY 100",
+         "DirectionOfTravel": "Both directions", "CountyName": "Westchester", "Description": "x" * 900,
+         "StartDate": "28/09/2026 09:00:00", "PlannedEndDate": "", "LastUpdated": "26/09/2026 14:01:12"}
+
+
+def setup_function():
+    app.dependency_overrides[require_service_or_firebase_token] = lambda: {"admin": True}
+    for feed in (ny511.cameras, ny511.events):
+        feed.items, feed.fetched_at, feed.error, feed._next_attempt = [], None, None, 0.0
+
+
+def teardown_function():
+    app.dependency_overrides.pop(require_service_or_firebase_token, None)
+
+
+def test_normalize_camera_skips_disabled_blocked_and_zero_coords():
+    assert ny511.normalize_camera(CAM)["image_url"] == "https://511ny.org/map/Cctv/1"
+    assert ny511.normalize_camera({**CAM, "Disabled": True}) is None
+    assert ny511.normalize_camera({**CAM, "Blocked": True}) is None
+    assert ny511.normalize_camera({**CAM, "Latitude": 0, "Longitude": 0}) is None
+
+
+def test_normalize_event_parses_day_first_dates_and_truncates_description():
+    e = ny511.normalize_event(EVENT)
+    assert e["start_local"] == "2026-09-28T09:00:00"   # DD/MM, not MM/DD
+    assert e["planned_end_local"] is None
+    assert len(e["description"]) == ny511._DESCRIPTION_MAX + 1
+
+
+def test_failed_refresh_keeps_last_good_data_and_reports_error():
+    feed = ny511._Feed("getcameras", 3600, ny511.normalize_camera)
+    with patch.object(ny511, "_fetch", AsyncMock(return_value=[ny511.normalize_camera(CAM)])):
+        asyncio.run(feed.get())
+    feed._next_attempt = 0.0
+    with patch.object(ny511, "_fetch", AsyncMock(side_effect=RuntimeError("boom"))):
+        asyncio.run(feed.get())
+    assert len(feed.items) == 1 and feed.fetched_at is not None
+    assert "boom" in feed.error
+    assert feed._next_attempt - feed.fetched_at <= ny511.RETRY_AFTER_FAILURE_S + 5  # retries soon, not after the full TTL
+
+
+def test_schema_change_is_an_error_not_an_empty_layer():
+    class Resp:
+        def raise_for_status(self): pass
+        def json(self): return [{"lat": 1, "lng": 2}]   # renamed fields -> nothing parses
+
+    class Client:
+        async def __aenter__(self): return self
+        async def __aexit__(self, *a): pass
+        async def get(self, *a, **k): return Resp()
+
+    with patch.object(ny511.httpx, "AsyncClient", lambda **k: Client()):
+        try:
+            asyncio.run(ny511._fetch("getcameras", ny511.normalize_camera))
+            assert False, "expected a schema-change error"
+        except ValueError as e:
+            assert "schema" in str(e)
+
+
+def test_endpoint_filters_to_bbox_and_reports_status():
+    far = {**CAM, "ID": "NYSDOT-2", "Latitude": 42.9, "Longitude": -78.8}   # Buffalo
+    for feed, rows, norm in ((ny511.cameras, [CAM, far], ny511.normalize_camera), (ny511.events, [EVENT], ny511.normalize_event)):
+        feed.items = [norm(r) for r in rows]
+        feed.fetched_at, feed._next_attempt = 1.0, float("inf")
+    r = client.get("/traffic/511", params={"south": 40.9, "west": -74.0, "north": 41.4, "east": -73.4})
+    assert r.status_code == 200
+    body = r.json()
+    assert [c["id"] for c in body["cameras"]] == ["NYSDOT-1"]
+    assert body["cameras_status"] == {"fetched_at": 1.0, "error": None, "total_in_bbox": 1, "truncated": False}
+    assert len(body["events"]) == 1
+
+
+def test_endpoint_rejects_inverted_bbox():
+    r = client.get("/traffic/511", params={"south": 41.4, "west": -74.0, "north": 40.9, "east": -73.4})
+    assert r.status_code == 400

drb-c2-core/tests/test_telemetry.py

@@ -24,6 +24,11 @@ def _override(decoded: dict):
 
 def teardown_function():
     app.dependency_overrides.pop(require_node_service_or_firebase_token, None)
+    telemetry._last_position.clear()
+
+
+def _writes_to(mock_set, collection_prefix: str):
+    return [c for c in mock_set.await_args_list if c.args[0].startswith(collection_prefix)]
 
 
 def test_service_token_without_node_id_is_rejected():
@@ -41,8 +46,9 @@ def test_node_upload_upserts_and_stamps_org_id():
         })
     assert resp.status_code == 200
     assert resp.json() == {"ok": True, "count": 1}
-    mock_set.assert_awaited_once()
-    (collection, doc_id, doc), kwargs = mock_set.await_args
+    snapshot = [c for c in mock_set.await_args_list if c.args[0] == "aircraft"]
+    assert len(snapshot) == 1
+    (collection, doc_id, doc), kwargs = snapshot[0]
     assert collection == "aircraft"
     assert doc_id == "A1B2C3"
     assert doc["node_id"] == "node-1"
@@ -92,3 +98,38 @@ def test_ais_node_upload_skips_entries_missing_mmsi():
     assert resp.status_code == 200
     assert resp.json() == {"ok": True, "count": 0}
     mock_set.assert_not_awaited()
+
+
+def _post_adsb(aircraft):
+    with patch.object(telemetry.fstore, "doc_get_cached", AsyncMock(return_value={"org_id": "org-A"})), \
+         patch.object(telemetry.fstore, "doc_set", AsyncMock()) as mock_set:
+        resp = client.post("/telemetry/adsb", json={"aircraft": aircraft})
+    assert resp.status_code == 200
+    return mock_set
+
+
+def test_position_writes_trail_point_with_ttl():
+    _override({"node": True, "node_id": "node-1"})
+    mock_set = _post_adsb([{"icao": "A1B2C3", "lat": 41.1, "lon": -73.8, "altitude_ft": 3000}])
+    trail = _writes_to(mock_set, "aircraft/A1B2C3/positions")
+    assert len(trail) == 1
+    (_, doc_id, point), _ = trail[0]
+    assert doc_id.isdigit()
+    assert (point["lat"], point["lon"], point["altitude_ft"]) == (41.1, -73.8, 3000)
+    assert point["expire_at"] > telemetry.datetime.now(telemetry.timezone.utc)
+
+
+def test_unchanged_position_is_not_rewritten_to_trail():
+    _override({"node": True, "node_id": "node-1"})
+    _post_adsb([{"icao": "A1B2C3", "lat": 41.1, "lon": -73.8}])
+    again = _post_adsb([{"icao": "A1B2C3", "lat": 41.1, "lon": -73.8}])
+    moved = _post_adsb([{"icao": "A1B2C3", "lat": 41.2, "lon": -73.8}])
+    assert _writes_to(again, "aircraft/A1B2C3/positions") == []
+    assert len(_writes_to(moved, "aircraft/A1B2C3/positions")) == 1
+
+
+def test_aircraft_without_position_gets_no_trail_point():
+    _override({"node": True, "node_id": "node-1"})
+    mock_set = _post_adsb([{"icao": "A1B2C3", "callsign": "UAL123"}])
+    assert _writes_to(mock_set, "aircraft/A1B2C3/positions") == []
+    assert len(_writes_to(mock_set, "aircraft")) == 1

drb-frontend/app/globals.css

@@ -177,6 +177,18 @@ html:not(.dark) .border-indigo-800 { border-color: #a5b4fc !important; }
   z-index: 0;
 }
 
+/* Pinned 511 camera tiles (MapView DotCameraLayer): strip Leaflet's tooltip
+ * padding and let the tile's own theme colours show, so the tile is no bigger
+ * than the video it holds. */
+.leaflet-tooltip.drb-cam-pin {
+  padding: 0;
+  border-radius: 6px;
+  background: var(--surface);
+  border: 1px solid var(--line-strong);
+  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.45);
+  white-space: normal;
+}
+
 /* ── Form inputs ─────────────────────────────────────────────────────────── */
 html:not(.dark) input:not([type="submit"]):not([type="button"]):not([type="reset"]),
 html:not(.dark) select,

drb-frontend/app/nodes/[id]/page.tsx

@@ -8,6 +8,7 @@ import { useSystems } from "@/lib/useSystems";
 import { useCalls } from "@/lib/useCalls";
 import { StatusBadge } from "@/components/StatusBadge";
 import { NodeConfigModal } from "@/components/NodeConfigModal";
+import { SecondarySdrPriority } from "@/components/SecondarySdrPriority";
 import { CallRow } from "@/components/CallRow";
 import { MachineOutputNotice } from "@/components/ui/MachineOutputNotice";
 import { useAuth } from "@/components/AuthProvider";
@@ -336,6 +337,8 @@ export default function NodeDetailPage() {
         )}
       </div>
 
+      <SecondarySdrPriority node={node} canEdit={isAdmin} />
+
       {/* Recent calls */}
       <section>
         <h2 className="text-sm font-semibold text-gray-400 uppercase tracking-wider mb-3">Recent Calls</h2>

drb-frontend/components/CameraFeed.tsx

@@ -0,0 +1,64 @@
+"use client";
+
+import { useEffect, useRef, useState } from "react";
+import type HlsType from "hls.js";
+import type { Ny511Camera } from "@/lib/types";
+
+// 511NY stills are served with max-age=60, so refreshing faster buys nothing.
+const SNAPSHOT_REFRESH_MS = 60_000;
+
+/**
+ * One 511NY camera: the live HLS stream when the camera has one (NYSDOT's
+ * skyvdn hosts send Access-Control-Allow-Origin: *), otherwise its snapshot on
+ * a timer. A stream that fails falls back to the snapshot rather than a black box.
+ */
+export function CameraFeed({ camera, className }: { camera: Ny511Camera; className?: string }) {
+  const videoRef = useRef<HTMLVideoElement>(null);
+  const [videoFailed, setVideoFailed] = useState(false);
+  const [tick, setTick] = useState(() => Date.now());
+  const useVideo = !!camera.video_url && !videoFailed;
+
+  useEffect(() => {
+    if (useVideo) return;
+    const id = setInterval(() => setTick(Date.now()), SNAPSHOT_REFRESH_MS);
+    return () => clearInterval(id);
+  }, [useVideo]);
+
+  useEffect(() => {
+    const video = videoRef.current;
+    const src = camera.video_url;
+    if (!useVideo || !video || !src) return;
+    let hls: HlsType | null = null;
+    let cancelled = false;
+
+    if (video.canPlayType("application/vnd.apple.mpegurl")) {
+      video.src = src;   // Safari/iOS play HLS natively
+    } else {
+      import("hls.js")
+        .then(({ default: Hls }) => {
+          if (cancelled) return;
+          if (!Hls.isSupported()) { setVideoFailed(true); return; }
+          hls = new Hls({ maxBufferLength: 10, backBufferLength: 0 });
+          hls.on(Hls.Events.ERROR, (_evt, data) => { if (data.fatal) setVideoFailed(true); });
+          hls.loadSource(src);
+          hls.attachMedia(video);
+        })
+        .catch(() => setVideoFailed(true));
+    }
+    return () => {
+      cancelled = true;
+      hls?.destroy();
+      video.removeAttribute("src");
+      video.load();   // stop the download, not just the playback
+    };
+  }, [useVideo, camera.video_url]);
+
+  if (useVideo) {
+    return <video ref={videoRef} muted autoPlay playsInline className={className} onError={() => setVideoFailed(true)} />;
+  }
+  if (!camera.image_url) {
+    return <div className={`${className ?? ""} flex items-center justify-center text-[10px] text-ink-muted`}>No image</div>;
+  }
+  // eslint-disable-next-line @next/next/no-img-element
+  return <img src={`${camera.image_url}?t=${tick}`} alt={`Camera: ${camera.name}`} className={className} />;
+}

drb-frontend/components/MapView.tsx

@@ -1,6 +1,7 @@
 "use client";
 
-import { useCallback, useEffect, useMemo, useState } from "react";
+import { useCallback, useEffect, useMemo, useRef, useState } from "react";
+import { createPortal } from "react-dom";
 import {
   FeatureGroup,
   LayersControl,
@@ -9,14 +10,20 @@ import {
   Polyline,
   Popup,
   TileLayer,
+  Tooltip,
   useMap,
+  useMapEvents,
 } from "react-leaflet";
 import L from "leaflet";
-import type { CallRecord, IncidentRecord, NodeRecord, NodeStatus } from "@/lib/types";
+import type { AircraftTrack, CallRecord, IncidentRecord, NodeRecord, NodeStatus } from "@/lib/types";
 import { isKnownSeverity, SEVERITY_COLORS, SEVERITY_LABEL, type Severity } from "@/lib/severity";
 import { MachineOutputNotice } from "@/components/ui/MachineOutputNotice";
 import { useAircraft } from "@/lib/useAircraft";
+import { useAircraftTrail } from "@/lib/useAircraftTrail";
 import { useVessels } from "@/lib/useVessels";
+import { use511 } from "@/lib/use511";
+import type { Ny511Camera, Ny511Event, Ny511FeedStatus } from "@/lib/types";
+import { CameraFeed } from "@/components/CameraFeed";
 
 // ── Leaflet icon fix ──────────────────────────────────────────────────────────
 delete (L.Icon.Default.prototype as unknown as Record<string, unknown>)._getIconUrl;
@@ -92,34 +99,151 @@ function nodeIcon(status: NodeStatus): L.DivIcon {
   });
 }
 
-// ── Aircraft icon — node-26#9 second-SDR ADS-B overlay ────────────────────────
-function aircraftIcon(trackDeg: number | null): L.DivIcon {
-  const size = 16;
-  const rotation = trackDeg ?? 0;
+// ── Aircraft — node-26#9 second-SDR ADS-B overlay ─────────────────────────────
+// Styled after ADS-B Exchange / tar1090: a sized airliner silhouette with a
+// dark outline, filled by altitude on tar1090's hue ramp, so height reads at a
+// glance and the icon stands out from OSM's own (purple) airport symbols.
+const ALT_HUE_STOPS: [number, number][] = [
+  [0, 20], [2000, 32.5], [4000, 43], [6000, 54], [8000, 72], [9000, 85], [11000, 140], [40000, 300],
+];
+
+function altitudeColor(altFt: number | null): string {
+  if (altFt == null) return "hsl(0, 0%, 55%)";
+  if (altFt <= 0) return "hsl(0, 0%, 45%)"; // on the ground
+  let hue = ALT_HUE_STOPS[ALT_HUE_STOPS.length - 1][1];
+  for (let i = 1; i < ALT_HUE_STOPS.length; i++) {
+    const [a1, h1] = ALT_HUE_STOPS[i];
+    if (altFt <= a1) {
+      const [a0, h0] = ALT_HUE_STOPS[i - 1];
+      hue = h0 + ((h1 - h0) * (altFt - a0)) / (a1 - a0);
+      break;
+    }
+  }
+  return `hsl(${hue.toFixed(0)}, 88%, 48%)`;
+}
+
+// Legend ticks for the altitude ramp, evenly spaced (the ramp itself isn't linear).
+const ALTITUDE_LEGEND_TICKS: [number, string][] = [
+  [1000, "1k"], [4000, "4k"], [10000, "10k"], [20000, "20k"], [40000, "40k"],
+];
+
+const AIRLINER_PATH =
+  "M32 2 C34.2 2 35.2 5 35.2 8 L35.2 23 L61 37.5 L61 42 L35.2 35 L34.2 51 L42.5 57.5 L42.5 61 L32 58.5 " +
+  "L21.5 61 L21.5 57.5 L29.8 51 L28.8 35 L3 42 L3 37.5 L28.8 23 L28.8 8 C28.8 5 29.8 2 32 2 Z";
+
+function aircraftIcon(trackDeg: number | null, altFt: number | null, selected: boolean): L.DivIcon {
+  const size = selected ? 36 : 30;
+  const outline = selected ? "#ffffff" : "#000000";
+  const shadow = selected ? "drop-shadow(0 0 3px #000)" : "drop-shadow(0 1px 1px rgba(0,0,0,.45))";
   return L.divIcon({
     className: "",
-    html: `<div style="width:${size}px;height:${size}px;transform:rotate(${rotation}deg)"><svg width="${size}" height="${size}" viewBox="0 0 24 24" fill="var(--accent)" stroke="var(--surface)" stroke-width="1"><path d="M12 2 L15 11 L22 15 L15 15.5 L14 21 L17 22.5 L12 21.5 L7 22.5 L10 21 L9 15.5 L2 15 L9 11 Z"/></svg></div>`,
+    html:
+      `<div style="width:${size}px;height:${size}px;transform:rotate(${trackDeg ?? 0}deg);filter:${shadow}">` +
+      `<svg width="${size}" height="${size}" viewBox="0 0 64 64"><path d="${AIRLINER_PATH}" ` +
+      `fill="${altitudeColor(altFt)}" stroke="${outline}" stroke-width="${selected ? 3 : 2}" stroke-linejoin="round"/></svg></div>`,
     iconSize: [size, size],
     iconAnchor: [size / 2, size / 2],
   });
 }
 
-function AircraftLayer() {
-  const { aircraft } = useAircraft();
+function AircraftTrail({ icao, current }: { icao: string; current: AircraftTrack }) {
+  const trail = useAircraftTrail(icao);
+  // Extend to the live position so the path always meets the icon.
+  const points = [...trail];
+  if (current.lat != null && current.lon != null) {
+    points.push({ lat: current.lat, lon: current.lon, altitude_ft: current.altitude_ft, t: current.last_seen });
+  }
+  // One segment per leg, colored by altitude like tar1090's track.
   return (
     <>
-      {aircraft
-        .filter((a) => a.lat != null && a.lon != null)
-        .map((a) => (
-          <Marker key={a.icao} position={[a.lat as number, a.lon as number]} icon={aircraftIcon(a.track_deg)}>
-            <Popup minWidth={160}>
-              <div className="space-y-1">
-                <div className="font-semibold">{a.callsign || a.icao}</div>
-                <div className="text-xs text-ink-muted">ICAO {a.icao}</div>
-                {a.altitude_ft != null && <div className="text-xs">Altitude: {Math.round(a.altitude_ft)} ft</div>}
-                {a.ground_speed_kt != null && <div className="text-xs">Speed: {Math.round(a.ground_speed_kt)} kt</div>}
+      {points.slice(1).map((p, i) => (
+        <Polyline
+          key={`${icao}-${i}`}
+          positions={[[points[i].lat, points[i].lon], [p.lat, p.lon]]}
+          pathOptions={{ color: altitudeColor(p.altitude_ft), weight: 3, opacity: 0.9, lineCap: "round" }}
+          interactive={false}
+        />
+      ))}
+    </>
+  );
+}
+
+function Stat({ label, value }: { label: string; value: string }) {
+  return (
+    <div>
+      <div className="text-[10px] uppercase tracking-wide text-ink-muted">{label}</div>
+      <div className="text-ink font-medium tabular-nums">{value}</div>
     </div>
-            </Popup>
+  );
+}
+
+// Details dock at the right edge (bottom sheet on phones, above the incident
+// drawer) instead of a popup over the plane, so the trail stays visible and
+// the map can be panned to follow it.
+function AircraftPanel({ a, onClose }: { a: AircraftTrack; onClose: () => void }) {
+  const ref = useRef<HTMLDivElement>(null);
+  useEffect(() => {
+    // The panel is portaled into the Leaflet container, whose native listeners
+    // would otherwise treat clicks/scrolls here as map clicks (deselect) or zoom.
+    if (!ref.current) return;
+    L.DomEvent.disableClickPropagation(ref.current);
+    L.DomEvent.disableScrollPropagation(ref.current);
+  }, []);
+  const fmt = (n: number | null, unit: string) => (n == null ? "—" : `${Math.round(n).toLocaleString()} ${unit}`);
+  return (
+    <div
+      ref={ref}
+      className="absolute left-3 right-3 bottom-12 md:left-auto md:bottom-auto md:top-[5.5rem] md:right-3 md:w-60 z-[1002] bg-surface/95 backdrop-blur-sm border border-line rounded-lg shadow-lg text-xs"
+    >
+      <div className="flex items-start justify-between gap-2 px-3 pt-2.5 pb-2 border-b border-line">
+        <div className="min-w-0">
+          <div className="flex items-center gap-1.5">
+            <span className="inline-block w-2.5 h-2.5 rounded-full shrink-0" style={{ background: altitudeColor(a.altitude_ft) }} />
+            <span className="text-ink font-semibold text-sm truncate">{a.callsign || a.icao}</span>
+          </div>
+          <div className="text-ink-muted mt-0.5">ICAO {a.icao}</div>
+        </div>
+        <button onClick={onClose} aria-label="Close aircraft details" className="text-ink-muted hover:text-ink px-1 leading-none text-base">
+          ×
+        </button>
+      </div>
+      <div className="grid grid-cols-2 gap-x-3 gap-y-2 px-3 py-2.5">
+        <Stat label="Altitude" value={fmt(a.altitude_ft, "ft")} />
+        <Stat label="Speed" value={fmt(a.ground_speed_kt, "kt")} />
+        <Stat label="Heading" value={a.track_deg == null ? "—" : `${Math.round(a.track_deg)}°`} />
+        <Stat label="Last heard" value={timeAgo(new Date(a.last_seen))} />
+      </div>
+    </div>
+  );
+}
+
+function AircraftLayer() {
+  const map = useMap();
+  const { aircraft } = useAircraft();
+  const [selected, setSelected] = useState<string | null>(null);
+  const positioned = aircraft.filter((a) => a.lat != null && a.lon != null);
+  const selectedTrack = positioned.find((a) => a.icao === selected);
+
+  // Clicking empty map deselects; marker clicks don't reach the map.
+  useMapEvents({ click: () => setSelected(null) });
+
+  return (
+    <>
+      {selectedTrack && <AircraftTrail icao={selectedTrack.icao} current={selectedTrack} />}
+      {selectedTrack &&
+        createPortal(<AircraftPanel a={selectedTrack} onClose={() => setSelected(null)} />, map.getContainer())}
+      {positioned.map((a) => (
+        <Marker
+          key={a.icao}
+          position={[a.lat as number, a.lon as number]}
+          icon={aircraftIcon(a.track_deg, a.altitude_ft, a.icao === selected)}
+          zIndexOffset={a.icao === selected ? 1000 : 0}
+          eventHandlers={{ click: () => setSelected((cur) => (cur === a.icao ? null : a.icao)) }}
+        >
+          <Tooltip direction="top" offset={[0, -14]}>
+            {a.callsign || a.icao}
+            {a.altitude_ft != null && ` · ${Math.round(a.altitude_ft).toLocaleString()} ft`}
+          </Tooltip>
         </Marker>
       ))}
     </>
@@ -127,12 +251,34 @@ function AircraftLayer() {
 }
 
 // ── Vessel icon — node-26#9 second-SDR AIS overlay ─────────────────────────────
+// MMSI 99xxxxxxx is an aid to navigation (buoy, beacon, light), not a vessel —
+// on the Hudson most of what a node hears is buoys (server-26#186).
+function isAidToNavigation(mmsi: string): boolean {
+  return /^99\d{7}$/.test(mmsi);
+}
+
+// AIS reports heading 511 (and course 360) for "not available".
+function aisHeading(deg: number | null): number | null {
+  return deg == null || deg >= 360 ? null : deg;
+}
+
 function vesselIcon(headingDeg: number | null): L.DivIcon {
-  const size = 14;
-  const rotation = headingDeg ?? 0;
+  const size = 22;
   return L.divIcon({
     className: "",
-    html: `<div style="width:${size}px;height:${size}px;transform:rotate(${rotation}deg)"><svg width="${size}" height="${size}" viewBox="0 0 24 24" fill="var(--accent)" stroke="var(--surface)" stroke-width="1"><path d="M12 2 L18 14 L18 20 L6 20 L6 14 Z"/></svg></div>`,
+    html:
+      `<div style="width:${size}px;height:${size}px;transform:rotate(${aisHeading(headingDeg) ?? 0}deg);filter:drop-shadow(0 1px 1px rgba(0,0,0,.45))">` +
+      `<svg width="${size}" height="${size}" viewBox="0 0 24 24"><path d="M12 2 L18 12 L18 21 L6 21 L6 12 Z" fill="hsl(190, 80%, 42%)" stroke="#000" stroke-width="1.25" stroke-linejoin="round"/></svg></div>`,
+    iconSize: [size, size],
+    iconAnchor: [size / 2, size / 2],
+  });
+}
+
+function aidToNavigationIcon(): L.DivIcon {
+  const size = 12;
+  return L.divIcon({
+    className: "",
+    html: `<svg width="${size}" height="${size}" viewBox="0 0 12 12"><rect x="2" y="2" width="8" height="8" transform="rotate(45 6 6)" fill="hsl(50, 95%, 55%)" stroke="#000" stroke-width="1"/></svg>`,
     iconSize: [size, size],
     iconAnchor: [size / 2, size / 2],
   });
@@ -144,17 +290,181 @@ function VesselLayer() {
     <>
       {vessels
         .filter((v) => v.lat != null && v.lon != null)
-        .map((v) => (
-          <Marker key={v.mmsi} position={[v.lat as number, v.lon as number]} icon={vesselIcon(v.heading_deg)}>
+        .map((v) => {
+          const aton = isAidToNavigation(v.mmsi);
+          return (
+            <Marker
+              key={v.mmsi}
+              position={[v.lat as number, v.lon as number]}
+              icon={aton ? aidToNavigationIcon() : vesselIcon(v.heading_deg)}
+              zIndexOffset={aton ? -100 : 0}
+            >
               <Popup minWidth={160}>
                 <div className="space-y-1">
-                <div className="font-semibold">{v.name || v.mmsi}</div>
+                  <div className="font-semibold">{aton ? `Aid to navigation${v.name ? ` ${v.name}` : ""}` : v.name || v.mmsi}</div>
                   <div className="text-xs text-ink-muted">MMSI {v.mmsi}</div>
-                {v.speed_kt != null && <div className="text-xs">Speed: {Math.round(v.speed_kt)} kt</div>}
+                  {!aton && v.speed_kt != null && <div className="text-xs">Speed: {Math.round(v.speed_kt)} kt</div>}
+                </div>
+              </Popup>
+            </Marker>
+          );
+        })}
+    </>
+  );
+}
+
+// ── 511NY traffic layers (server-26#183) ─────────────────────────────────────
+// Overlay names double as the event keys for overlayadd/overlayremove.
+const OVERLAY_DOT_CAMERAS = "DOT Cameras";
+const OVERLAY_TRAFFIC_EVENTS = "Traffic Events";
+
+/** True while the named LayersControl overlay is checked. Overlays start unchecked. */
+function useOverlayShown(map: L.Map, name: string): boolean {
+  const [shown, setShown] = useState(false);
+  useEffect(() => {
+    const on = (e: L.LayersControlEvent) => e.name === name && setShown(true);
+    const off = (e: L.LayersControlEvent) => e.name === name && setShown(false);
+    map.on("overlayadd", on);
+    map.on("overlayremove", off);
+    return () => { map.off("overlayadd", on); map.off("overlayremove", off); };
+  }, [map, name]);
+  return shown;
+}
+
+function cameraIcon(): L.DivIcon {
+  return L.divIcon({
+    className: "",
+    html: `<svg width="16" height="12" viewBox="0 0 16 12"><rect x="0.5" y="1.5" width="11" height="9" rx="2" fill="#1e3a5f" stroke="#93c5fd" stroke-width="1"/><circle cx="6" cy="6" r="2.5" fill="none" stroke="#93c5fd" stroke-width="1.25"/><polygon points="12,4 15.5,2 15.5,10 12,8" fill="#93c5fd"/></svg>`,
+    iconSize: [16, 12],
+    iconAnchor: [8, 6],
+  });
+}
+
+// Shape + glyph per 511 event type, so the layer reads without colour alone.
+const EVENT_STYLE: Record<string, { glyph: string; fill: string; label: string }> = {
+  accidentsAndIncidents: { glyph: "!", fill: "#dc2626", label: "Accident / incident" },
+  closures: { glyph: "×", fill: "#ea580c", label: "Closure" },
+  roadwork: { glyph: "W", fill: "#ca8a04", label: "Roadwork" },
+  specialEvents: { glyph: "E", fill: "#7c3aed", label: "Special event" },
+  transitOperations: { glyph: "T", fill: "#0891b2", label: "Transit" },
+};
+const EVENT_STYLE_OTHER = { glyph: "i", fill: "#6b7280", label: "Other" };
+
+function trafficEventIcon(type: string): L.DivIcon {
+  const st = EVENT_STYLE[type] ?? EVENT_STYLE_OTHER;
+  return L.divIcon({
+    className: "",
+    html: `<svg width="16" height="16" viewBox="0 0 16 16"><rect x="1" y="1" width="14" height="14" rx="3" fill="${st.fill}" stroke="#000" stroke-width="1"/><text x="8" y="12" text-anchor="middle" font-size="11" font-weight="700" font-family="sans-serif" fill="#fff">${st.glyph}</text></svg>`,
+    iconSize: [16, 16],
+    iconAnchor: [8, 8],
+  });
+}
+
+function fmtLocal(iso: string | null): string | null {
+  if (!iso) return null;
+  const d = new Date(iso);   // naive ISO parses as browser-local; 511NY stamps are NY local
+  return isNaN(d.getTime()) ? null : d.toLocaleString([], { month: "short", day: "numeric", hour: "numeric", minute: "2-digit" });
+}
+
+/** Surfaces a dead or stale 511 feed on the map instead of an unexplained empty layer. */
+function FeedProblem({ map, label, status, fetchError }: { map: L.Map; label: string; status?: Ny511FeedStatus; fetchError: string | null }) {
+  let msg: string | null = null;
+  if (fetchError) msg = `${label}: could not reach server`;
+  else if (status?.error) {
+    const age = status.fetched_at ? `showing data from ${Math.round((Date.now() / 1000 - status.fetched_at) / 60)} min ago` : "no data yet";
+    msg = `${label}: 511NY feed error, ${age}`;
+  } else if (status?.truncated) msg = `${label}: showing ${1500} of ${status.total_in_bbox} — zoom in`;
+  if (!msg) return null;
+  return createPortal(
+    <div className="absolute bottom-8 left-3 z-[1001] bg-surface/90 border border-line rounded px-2 py-1 text-xs text-ink-2 pointer-events-none">{msg}</div>,
+    map.getContainer(),
+  );
+}
+
+// Pinned cameras: clicking a camera's snapshot pins its live feed as a small
+// tile anchored at the camera, so several views along one road can be read
+// against the map. Oldest pin drops past the cap.
+const MAX_CAMERA_PINS = 6;
+
+function DotCameraLayer() {
+  const map = useMap();
+  const shown = useOverlayShown(map, OVERLAY_DOT_CAMERAS);
+  const { data, error } = use511(map, "cameras", shown);
+  const [pinned, setPinned] = useState<Ny511Camera[]>([]);
+  const pinnedIds = useMemo(() => new Set(pinned.map((c) => c.id)), [pinned]);
+
+  const pin = (c: Ny511Camera) => {
+    map.closePopup();
+    setPinned((prev) => (prev.some((p) => p.id === c.id) ? prev : [...prev, c].slice(-MAX_CAMERA_PINS)));
+  };
+  const unpin = (id: string) => setPinned((prev) => prev.filter((p) => p.id !== id));
+
+  return (
+    <>
+      {shown && <FeedProblem map={map} label="DOT cameras" status={data.cameras_status} fetchError={error} />}
+      {(data.cameras ?? []).filter((c) => !pinnedIds.has(c.id)).map((c) => (
+        <Marker key={c.id} position={[c.lat, c.lon]} icon={cameraIcon()}>
+          <Popup minWidth={260} maxWidth={340}>
+            <div className="space-y-1">
+              <div className="font-semibold">{c.name}</div>
+              {c.roadway && <div className="text-xs text-ink-muted">{c.roadway}{c.direction && c.direction !== "Unknown" ? ` · ${c.direction}` : ""}</div>}
+              {c.image_url && (
+                // Popup content mounts on open, so the timestamp busts the cache per open.
+                <button type="button" onClick={() => pin(c)} title="Pin this camera to the map" className="block w-full p-0 border-0 bg-transparent cursor-pointer">
+                  {/* eslint-disable-next-line @next/next/no-img-element */}
+                  <img src={`${c.image_url}?t=${Date.now()}`} alt={`Camera: ${c.name}`} className="w-full rounded border border-line" loading="lazy" />
+                </button>
+              )}
+              <div className="text-[10px] text-ink-muted">
+                Click the image to pin {c.video_url ? "the live feed" : "it"} to the map · 511NY / NYSDOT
+              </div>
             </div>
           </Popup>
         </Marker>
       ))}
+      {/* Players only exist while the overlay is on, so hiding it stops every stream. */}
+      {shown && pinned.map((c) => (
+        <Marker key={`pin-${c.id}`} position={[c.lat, c.lon]} icon={cameraIcon()} zIndexOffset={300}>
+          <Tooltip permanent interactive direction="top" offset={[0, -8]} opacity={1} className="drb-cam-pin">
+            <div className="w-[192px]">
+              <div className="flex items-center gap-1 px-1.5 h-4">
+                <span className="flex-1 truncate text-[10px] leading-4 text-ink-2" title={c.name}>{c.name}</span>
+                <button type="button" onClick={() => unpin(c.id)} aria-label={`Unpin ${c.name}`} className="text-ink-muted hover:text-ink text-xs leading-none px-0.5">×</button>
+              </div>
+              <CameraFeed camera={c} className="block w-[192px] h-[108px] object-cover bg-black rounded-b" />
+            </div>
+          </Tooltip>
+        </Marker>
+      ))}
+    </>
+  );
+}
+
+function TrafficEventLayer() {
+  const map = useMap();
+  const shown = useOverlayShown(map, OVERLAY_TRAFFIC_EVENTS);
+  const { data, error } = use511(map, "events", shown);
+  return (
+    <>
+      {shown && <FeedProblem map={map} label="Traffic events" status={data.events_status} fetchError={error} />}
+      {(data.events ?? []).map((e: Ny511Event) => {
+        const st = EVENT_STYLE[e.type] ?? EVENT_STYLE_OTHER;
+        const start = fmtLocal(e.start_local);
+        const end = fmtLocal(e.planned_end_local);
+        return (
+          <Marker key={e.id} position={[e.lat, e.lon]} icon={trafficEventIcon(e.type)} zIndexOffset={e.type === "accidentsAndIncidents" ? 200 : 0}>
+            <Popup minWidth={220} maxWidth={320}>
+              <div className="space-y-1">
+                <div className="font-semibold">{st.label}{e.subtype ? `: ${e.subtype}` : ""}</div>
+                <div className="text-xs text-ink-muted">{[e.roadway, e.direction, e.county].filter(Boolean).join(" · ")}</div>
+                {(start || end) && <div className="text-xs">{start ? `From ${start}` : ""}{end ? ` until ${end}` : ""}</div>}
+                <div className="text-xs whitespace-pre-line">{e.description}</div>
+                <div className="text-[10px] text-ink-muted">511NY{e.updated_local ? ` · updated ${fmtLocal(e.updated_local)}` : ""}</div>
+              </div>
+            </Popup>
+          </Marker>
+        );
+      })}
     </>
   );
 }
@@ -528,6 +838,21 @@ export default function MapView({ nodes, activeCalls, incidents = [], calls = []
   const [drawerOpen, setDrawerOpen] = useState(false);
   const [agoClock, setAgoClock] = useState(0);
   const [radarEpoch, setRadarEpoch] = useState(() => Date.now());
+  const [aircraftShown, setAircraftShown] = useState(false);
+
+  // The altitude key only belongs in the legend while the opt-in Aircraft
+  // overlay is actually on (server-26#185).
+  useEffect(() => {
+    if (!mapInstance) return;
+    const on = (e: L.LayersControlEvent) => e.name === "Aircraft" && setAircraftShown(true);
+    const off = (e: L.LayersControlEvent) => e.name === "Aircraft" && setAircraftShown(false);
+    mapInstance.on("overlayadd", on);
+    mapInstance.on("overlayremove", off);
+    return () => {
+      mapInstance.off("overlayadd", on);
+      mapInstance.off("overlayremove", off);
+    };
+  }, [mapInstance]);
 
   useEffect(() => {
     const id = setInterval(() => setAgoClock((t: number) => t + 1), 10_000);
@@ -660,6 +985,18 @@ export default function MapView({ nodes, activeCalls, incidents = [], calls = []
             </FeatureGroup>
           </LayersControl.Overlay>
 
+          {/* Overlays: 511NY DOT cameras + traffic events (server-26#183), opt-in */}
+          <LayersControl.Overlay name={OVERLAY_DOT_CAMERAS}>
+            <FeatureGroup>
+              <DotCameraLayer />
+            </FeatureGroup>
+          </LayersControl.Overlay>
+          <LayersControl.Overlay name={OVERLAY_TRAFFIC_EVENTS}>
+            <FeatureGroup>
+              <TrafficEventLayer />
+            </FeatureGroup>
+          </LayersControl.Overlay>
+
           {/* Overlay: Weather Radar — NEXRAD via Iowa Env Mesonet; key forces remount on refresh */}
           <LayersControl.Overlay name="Weather Radar">
             <TileLayer
@@ -718,6 +1055,18 @@ export default function MapView({ nodes, activeCalls, incidents = [], calls = []
             </div>
           ))}
         </div>
+        {aircraftShown && (
+          <div className="border-t border-line pt-1.5 space-y-1">
+            <p className="text-ink-muted font-medium text-[10px] uppercase tracking-wide">Aircraft altitude</p>
+            <div
+              className="h-2 w-32 rounded-sm border border-line"
+              style={{ background: `linear-gradient(to right, ${ALTITUDE_LEGEND_TICKS.map(([ft], i) => `${altitudeColor(ft)} ${(i / (ALTITUDE_LEGEND_TICKS.length - 1)) * 100}%`).join(", ")})` }}
+            />
+            <div className="flex justify-between w-32 text-[10px] text-ink-2 tabular-nums">
+              {ALTITUDE_LEGEND_TICKS.map(([ft, label]) => <span key={ft}>{label}</span>)}
+            </div>
+          </div>
+        )}
         <div className="border-t border-line pt-1.5 space-y-1">
           <p className="text-ink-muted font-medium text-[10px] uppercase tracking-wide">Nodes</p>
           {([

drb-frontend/components/SecondarySdrPriority.tsx

@@ -0,0 +1,154 @@
+"use client";
+
+import { useEffect, useState } from "react";
+import { c2api } from "@/lib/c2api";
+import type { NodeRecord } from "@/lib/types";
+
+// node-26#9. OP25 always keeps its own SDR; every other SDR on the node runs
+// the next enabled item here, top first — so a 3-SDR node runs both.
+const MODES: { mode: string; name: string; hint: string }[] = [
+  { mode: "adsb", name: "ADS-B", hint: "Aircraft · 1090 MHz" },
+  { mode: "ais", name: "AIS", hint: "Vessels · 162 MHz" },
+];
+
+type Row = { mode: string; enabled: boolean };
+
+function rowsFrom(priority: string[]): Row[] {
+  return [
+    ...priority.filter((m) => MODES.some((x) => x.mode === m)).map((mode) => ({ mode, enabled: true })),
+    ...MODES.filter((x) => !priority.includes(x.mode)).map((x) => ({ mode: x.mode, enabled: false })),
+  ];
+}
+
+export function SecondarySdrPriority({ node, canEdit }: { node: NodeRecord; canEdit: boolean }) {
+  const priority = node.secondary_sdr_priority ?? [];
+  // null/absent = the node has never reported (older firmware, container down
+  // at checkin): unknown, not "nothing running" (server-26#187).
+  const reported = node.secondary_sdr_running != null;
+  const running = node.secondary_sdr_running ?? [];
+  const [rows, setRows] = useState<Row[]>(() => rowsFrom(priority));
+  const [dirty, setDirty] = useState(false);
+  const [saving, setSaving] = useState(false);
+  const [message, setMessage] = useState<string | null>(null);
+
+  // Follow the node's live checkin unless there are unsaved edits.
+  const priorityKey = priority.join(",");
+  useEffect(() => {
+    if (!dirty) setRows(rowsFrom(priorityKey ? priorityKey.split(",") : []));
+  }, [priorityKey, dirty]);
+
+  function edit(next: Row[]) {
+    setRows(next);
+    setDirty(true);
+    setMessage(null);
+  }
+
+  function move(i: number, delta: number) {
+    const next = [...rows];
+    [next[i], next[i + delta]] = [next[i + delta], next[i]];
+    edit(next);
+  }
+
+  async function save() {
+    setSaving(true);
+    setMessage(null);
+    try {
+      await c2api.updateNode(node.node_id, {
+        secondary_sdr_priority: rows.filter((r) => r.enabled).map((r) => r.mode),
+      });
+      setDirty(false);
+      setMessage("Sent to the node. Status updates when it checks in.");
+    } catch (err) {
+      setMessage(err instanceof Error ? err.message : "Save failed.");
+    } finally {
+      setSaving(false);
+    }
+  }
+
+  // Only quote a count the node actually sent alongside its running list; a
+  // bare sdr_count may be the Firestore default, not a report.
+  const sdrCount = reported ? node.sdr_count : undefined;
+  let rank = 0;
+
+  return (
+    <section>
+      <h2 className="text-sm font-semibold text-gray-400 uppercase tracking-wider mb-1">Secondary SDRs</h2>
+      <p className="text-xs text-gray-500 font-mono mb-3">
+        OP25 always keeps its own SDR. Every other SDR runs the next enabled item, top first.
+        {" "}
+        {sdrCount != null
+          ? `This node reports ${sdrCount} SDR${sdrCount === 1 ? "" : "s"} (${Math.max(sdrCount - 1, 0)} spare).`
+          : "This node hasn't reported its SDRs yet."}
+      </p>
+      <div className="bg-gray-900 border border-gray-800 rounded-lg divide-y divide-gray-800 font-mono text-sm">
+        {rows.map((row, i) => {
+          const meta = MODES.find((x) => x.mode === row.mode)!;
+          const isRunning = running.includes(row.mode);
+          const state = !row.enabled
+            ? "Off"
+            : dirty
+              ? "Unsaved"
+              : !reported
+                ? "Not reported"
+                : isRunning
+                  ? "Running"
+                  : "Waiting for SDR";
+          return (
+            <div key={row.mode} className="flex items-center gap-3 px-4 py-2.5">
+              <span className="w-4 text-right text-gray-600 text-xs">{row.enabled ? ++rank : ""}</span>
+              <input
+                type="checkbox"
+                checked={row.enabled}
+                disabled={!canEdit}
+                aria-label={`Enable ${meta.name}`}
+                onChange={(e) => edit(rows.map((r, j) => (j === i ? { ...r, enabled: e.target.checked } : r)))}
+                className="rounded bg-gray-800 border-gray-700 text-indigo-600 focus:ring-indigo-500 focus:ring-offset-gray-900"
+              />
+              <div className="flex-1 min-w-0">
+                <div className="text-gray-200">{meta.name}</div>
+                <div className="text-xs text-gray-500">{meta.hint}</div>
+              </div>
+              {canEdit && (
+                <div className="flex gap-1">
+                  <button
+                    type="button"
+                    onClick={() => move(i, -1)}
+                    disabled={i === 0}
+                    aria-label={`Move ${meta.name} up`}
+                    className="w-7 h-7 rounded bg-gray-800 hover:bg-gray-700 text-gray-300 disabled:opacity-30"
+                  >
+                    ▲
+                  </button>
+                  <button
+                    type="button"
+                    onClick={() => move(i, 1)}
+                    disabled={i === rows.length - 1}
+                    aria-label={`Move ${meta.name} down`}
+                    className="w-7 h-7 rounded bg-gray-800 hover:bg-gray-700 text-gray-300 disabled:opacity-30"
+                  >
+                    ▼
+                  </button>
+                </div>
+              )}
+              <span className={`w-28 text-right text-xs ${state === "Running" ? "text-green-400" : "text-gray-500"}`}>
+                {state}
+              </span>
+            </div>
+          );
+        })}
+      </div>
+      {canEdit && (
+        <div className="flex items-center gap-3 mt-3">
+          <button
+            onClick={save}
+            disabled={!dirty || saving}
+            className="px-4 py-2 bg-indigo-700 hover:bg-indigo-600 disabled:opacity-50 text-white rounded-lg text-sm font-mono transition-colors"
+          >
+            {saving ? "Saving…" : "Save priority"}
+          </button>
+          {message && <span className="text-xs text-gray-500 font-mono">{message}</span>}
+        </div>
+      )}
+    </section>
+  );
+}

drb-frontend/lib/c2api.ts

@@ -1,5 +1,5 @@
 import { auth } from "@/lib/firebase";
-import type { AreaContext, TalkgroupPending } from "@/lib/types";
+import type { AreaContext, Ny511Response, TalkgroupPending } from "@/lib/types";
 
 const BASE = process.env.NEXT_PUBLIC_C2_URL ?? "http://localhost:8000";
 
@@ -35,7 +35,10 @@ export const c2api = {
     request(`/nodes/${nodeId}/override/ack`, { method: "POST", body: JSON.stringify({ timeout_minutes: timeoutMinutes }) }),
   resetOverride: (nodeId: string) =>
     request(`/nodes/${nodeId}/override/reset`, { method: "POST" }),
-  updateNode: (id: string, body: { node_type?: string; enforce_override_timeout?: boolean }) =>
+  updateNode: (
+    id: string,
+    body: { node_type?: string; enforce_override_timeout?: boolean; secondary_sdr_priority?: string[] },
+  ) =>
     request(`/nodes/${id}`, { method: "PATCH", body: JSON.stringify(body) }),
 
   // Systems
@@ -367,6 +370,12 @@ export const c2api = {
   revokeEnrollmentToken: (tokenId: string) =>
     request(`/org/enrollment-tokens/${tokenId}`, { method: "DELETE" }),
 
+  // 511NY cameras/events inside a map bbox (server-26#183)
+  get511: (bbox: { south: number; west: number; north: number; east: number }, layers: string) =>
+    request<Ny511Response>(`/traffic/511?${new URLSearchParams({
+      south: String(bbox.south), west: String(bbox.west), north: String(bbox.north), east: String(bbox.east), layers,
+    })}`),
+
   // Public waitlist — no auth, see routers/waitlist.py
   joinWaitlist: (body: { email: string; org_name?: string; note?: string }) =>
     request<{ ok: boolean }>("/waitlist", { method: "POST", body: JSON.stringify(body) }),

drb-frontend/lib/types.ts

@@ -53,8 +53,12 @@ export interface NodeRecord {
   hardware_preset?: string;
   ppm_override?: number | null;
   node_type?: string;
-  secondary_sdr_mode?: string;
-  sdr_count?: number;
+  secondary_sdr_mode?: string; // legacy; priority[0] on current nodes
+  /** Ordered decoders for the SDRs beyond OP25's, run top-down (node-26#9). */
+  secondary_sdr_priority?: string[];
+  /** What the node's last checkin reported actually running. */
+  secondary_sdr_running?: string[] | null;
+  sdr_count?: number | null; // null = never reported
   enforce_override_timeout?: boolean;
   is_overridden?: boolean;
   override_system_id?: string | null;
@@ -74,6 +78,14 @@ export interface AircraftTrack {
   last_seen: string;
 }
 
+/** One point of an aircraft's flight path — aircraft/{icao}/positions. */
+export interface AircraftTrailPoint {
+  lat: number;
+  lon: number;
+  altitude_ft: number | null;
+  t: string;
+}
+
 export interface VesselTrack {
   mmsi: string;
   org_id?: string;
@@ -86,6 +98,49 @@ export interface VesselTrack {
   last_seen: string;
 }
 
+// 511NY traffic layer (server-26#183) — GET /traffic/511, cached server-side,
+// not Firestore. *_local times are New York local, no offset: display only.
+export interface Ny511Camera {
+  id: string;
+  lat: number;
+  lon: number;
+  name: string;
+  roadway: string;
+  direction: string;
+  image_url: string | null;
+  video_url: string | null;
+}
+
+export interface Ny511Event {
+  id: string;
+  lat: number;
+  lon: number;
+  type: string;
+  subtype: string;
+  severity: string;
+  roadway: string;
+  direction: string;
+  county: string;
+  description: string;
+  start_local: string | null;
+  planned_end_local: string | null;
+  updated_local: string | null;
+}
+
+export interface Ny511FeedStatus {
+  fetched_at: number | null;  // epoch seconds of the last successful 511NY fetch
+  error: string | null;       // set when the latest refresh failed (data is then stale)
+  total_in_bbox: number;
+  truncated: boolean;
+}
+
+export interface Ny511Response {
+  cameras?: Ny511Camera[];
+  cameras_status?: Ny511FeedStatus;
+  events?: Ny511Event[];
+  events_status?: Ny511FeedStatus;
+}
+
 export interface VocabularyPendingTerm {
   term: string;
   source: "induction" | "correction";

drb-frontend/lib/use511.ts

@@ -0,0 +1,57 @@
+"use client";
+
+import { useEffect, useRef, useState } from "react";
+import type L from "leaflet";
+import { c2api } from "@/lib/c2api";
+import type { Ny511Response } from "@/lib/types";
+
+// 511NY cameras/events for the current map view (server-26#183). Unlike
+// useAircraft/useVessels this is not a Firestore listener: the data is public
+// and statewide, so c2-core caches it in memory and serves a bbox slice.
+// Fetches only while `enabled` (the overlay is on), on pan/zoom (debounced),
+// and on a poll matching the server's events TTL.
+const POLL_MS = 2 * 60 * 1000;
+const MOVE_DEBOUNCE_MS = 400;
+const BBOX_PAD = 0.2;   // fetch a little past the edges so small pans don't blank the layer
+
+export function use511(map: L.Map, layers: "cameras" | "events", enabled: boolean) {
+  const [data, setData] = useState<Ny511Response>({});
+  const [error, setError] = useState<string | null>(null);
+  const seq = useRef(0);
+
+  useEffect(() => {
+    if (!enabled) { setData({}); return; }
+    let debounce: ReturnType<typeof setTimeout> | undefined;
+
+    const load = async () => {
+      const b = map.getBounds().pad(BBOX_PAD);
+      const mine = ++seq.current;
+      try {
+        const res = await c2api.get511(
+          { south: b.getSouth(), west: b.getWest(), north: b.getNorth(), east: b.getEast() },
+          layers,
+        );
+        if (mine !== seq.current) return;   // a newer pan's response wins
+        setData(res);
+        setError(null);
+      } catch (e) {
+        if (mine !== seq.current) return;
+        console.error("use511:", e);
+        setError(e instanceof Error ? e.message : String(e));
+      }
+    };
+    const onMove = () => { clearTimeout(debounce); debounce = setTimeout(load, MOVE_DEBOUNCE_MS); };
+
+    load();
+    map.on("moveend", onMove);
+    const poll = setInterval(load, POLL_MS);
+    return () => {
+      map.off("moveend", onMove);
+      clearTimeout(debounce);
+      clearInterval(poll);
+      seq.current++;   // drop any in-flight response
+    };
+  }, [map, layers, enabled]);
+
+  return { data, error };
+}

drb-frontend/lib/useAircraftTrail.ts

@@ -0,0 +1,43 @@
+"use client";
+
+import { useEffect, useState } from "react";
+import { collection, onSnapshot, orderBy, query, where, FirestoreError } from "firebase/firestore";
+import { db } from "@/lib/firebase";
+import type { AircraftTrailPoint } from "@/lib/types";
+
+// Trail points live at aircraft/{icao}/positions (written by c2-core
+// telemetry.py on every position change, TTL-deleted after ~24h). The same
+// icao can fly several legs a day, so only the latest continuous stretch is
+// "this flight": a gap longer than FLIGHT_GAP_MS starts a new one.
+const LOOKBACK_MS = 6 * 60 * 60 * 1000;
+const FLIGHT_GAP_MS = 20 * 60 * 1000;
+
+function currentFlight(points: AircraftTrailPoint[]): AircraftTrailPoint[] {
+  let start = 0;
+  for (let i = 1; i < points.length; i++) {
+    if (new Date(points[i].t).getTime() - new Date(points[i - 1].t).getTime() > FLIGHT_GAP_MS) start = i;
+  }
+  return points.slice(start);
+}
+
+/** Live flight path for one aircraft; pass null to subscribe to nothing. */
+export function useAircraftTrail(icao: string | null) {
+  const [trail, setTrail] = useState<AircraftTrailPoint[]>([]);
+
+  useEffect(() => {
+    setTrail([]);
+    if (!icao) return;
+    // `t` is Python's isoformat() in UTC ("...T17:06:48.755123+00:00"), so it
+    // sorts and range-filters correctly as a string against toISOString()'s
+    // "...T17:06:48.755Z" down to the second — no composite index needed.
+    const since = new Date(Date.now() - LOOKBACK_MS).toISOString();
+    const q = query(collection(db, "aircraft", icao, "positions"), where("t", ">=", since), orderBy("t"));
+    return onSnapshot(
+      q,
+      (snap) => setTrail(currentFlight(snap.docs.map((d) => d.data() as AircraftTrailPoint))),
+      (err: FirestoreError) => console.error("useAircraftTrail:", err),
+    );
+  }, [icao]);
+
+  return trail;
+}

drb-frontend/package.json

@@ -13,6 +13,7 @@
     "react": "^18.3.0",
     "react-dom": "^18.3.0",
     "firebase": "^10.12.0",
+    "hls.js": "^1.5.0",
     "leaflet": "^1.9.4",
 "react-leaflet": "^4.2.1",
     "react-markdown": "^9.0.1"

infra/firestore/firestore.indexes.json

@@ -77,5 +77,13 @@
       ]
     }
   ],
-  "fieldOverrides": []
+  "fieldOverrides": [
+    {
+      "//": "TTL: flight-trail points (aircraft/{icao}/positions, server-26 telemetry.py) are deleted ~24h after expire_at. indexes: [] because nothing queries on expire_at.",
+      "collectionGroup": "positions",
+      "fieldPath": "expire_at",
+      "ttl": true,
+      "indexes": []
+    }
+  ]
 }

infra/firestore/firestore.rules

@@ -98,6 +98,14 @@ service cloud.firestore {
     match /aircraft/{icao} {
       allow read: if docInMyOrg();
       allow write: if false;
+
+      // Flight trail points. Org is checked against the PARENT aircraft doc
+      // (one get() per query) so the map can query a trail by time alone,
+      // without an org_id filter and the composite index that would need.
+      match /positions/{pointId} {
+        allow read: if inOrg(get(/databases/$(database)/documents/aircraft/$(icao)).data.org_id);
+        allow write: if false;
+      }
     }
 
     match /vessels/{mmsi} {