fix(adsb): fix aircraft photo display and add Drone Intelligence docs

- Fix stale DOM refs in fetchAircraftPhoto: elements were captured before
  await fetch(), but showAircraftDetails rebuilds innerHTML on every RAF
  update, leaving the async path writing to detached nodes. Now re-queries
  the DOM after await, and the cache (synchronous) path queries inline so
  refs are always fresh.
- Add thumbnail fallback in aircraft_photo route: fall back to thumbnail
  when thumbnail_large.src is absent rather than returning null.
- Add Drone Intelligence to nav, help modal, cheat sheets, README, and docs.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docs/FEATURES.md

@@ -354,6 +354,42 @@ Technical Surveillance Countermeasures (TSCM) screening for detecting wireless s
 - No cryptographic de-randomization
 - Passive screening only (no active probing by default)
 
+## Drone Intelligence
+
+Multi-vector UAV detection and identification system combining three complementary detection methods into unified contact tracking.
+
+### Detection Vectors
+
+- **Remote ID (WiFi/BLE)** — Parses ASTM F3411-22a broadcast frames from WiFi Beacon and BLE Advertisement packets. Extracts drone ID, operator ID, drone type, GPS position, altitude, speed, and emergency status. Mandatory for all drones >250g in the US/EU since 2023.
+- **RTL-SDR RF (433/868 MHz)** — Monitors ISM bands for control link and telemetry signals characteristic of consumer and FPV drones. Detects DJI OcuSync, FrSky, FlySky, and generic FSK/GFSK drone control protocols.
+- **HackRF (2.4/5.8 GHz)** — Wide-scan of video downlink and telemetry bands used by most consumer drones. Detects power above noise floor across 2.400–2.483 GHz and 5.725–5.875 GHz ISM bands.
+
+### Contact Correlation
+
+The `DroneCorrelator` merges raw observations from all three vectors into unified `DroneContact` objects:
+- **TTL-based store** — contacts expire after 120 seconds of no activity
+- **Multi-vector fusion** — a single contact can be seen on 1–3 vectors simultaneously
+- **Deduplication** — observations from the same vector within 5 seconds are collapsed
+
+### Risk Scoring
+
+| Level | Criteria |
+|-------|----------|
+| High | No Remote ID broadcast (non-compliant) or ASTM non-conformant frame |
+| Medium | Multiple detection vectors active, or RSSI delta >15 dB between vectors |
+| Low | Compliant Remote ID present, single detection vector |
+
+### Live Map
+
+Remote ID contacts with GPS position data are plotted on a Leaflet map. Markers show drone ID and last known coordinates. Map updates in real time via SSE.
+
+### Requirements
+
+- WiFi adapter capable of monitor mode (for BLE/WiFi Remote ID)
+- RTL-SDR dongle (for 433/868 MHz RF detection)
+- HackRF One (optional, for 2.4/5.8 GHz detection)
+- Python package: `opendroneid>=1.0`
+
 ## Meshtastic Mesh Networks
 
 Integration with Meshtastic LoRa mesh networking devices for decentralized communication.

docs/USAGE.md

@@ -446,6 +446,35 @@ Digital Selective Calling monitoring runs alongside AIS:
 - Full functionality requires WiFi adapter, Bluetooth adapter, and SDR hardware
 - Threat detection uses a database of 47K+ known tracker fingerprints
 
+## Drone Intelligence
+
+1. **Open Mode** - Select "Drone Intel" from the Intel group in the navigation bar
+2. **Configure Interfaces** - Enter your WiFi interface name (must support monitor mode) for Remote ID detection
+3. **Set RTL-SDR Index** - If you have multiple RTL-SDR devices, enter the device index (default: 0)
+4. **Start** - Click "Start Scan" to activate all available detection vectors simultaneously
+5. **Monitor Contacts** - Detected drone contacts appear in the contact list with ID, vectors, risk level, and last seen time
+6. **View Map** - Contacts with GPS data from Remote ID are plotted on the live map
+
+### Detection Vectors
+
+- **Remote ID (WiFi/BLE)** — Passive sniff of 802.11 beacon frames and BLE advertisements. Decodes ASTM F3411 payloads: drone GPS, operator ID, drone type, speed, altitude, and emergency status
+- **433/868 MHz RF** — RTL-SDR scans ISM bands for drone control link and telemetry RF signatures
+- **2.4/5.8 GHz** — HackRF (if present) sweeps video downlink bands for active drone transmissions
+
+### Risk Levels
+
+- **High** — Drone operating without Remote ID (non-compliant) or malformed ASTM frame. Warrants immediate attention.
+- **Medium** — Contact detected on multiple RF vectors, or significant RSSI difference between vectors (>15 dB). May indicate evasion or multi-radio platform.
+- **Low** — Compliant Remote ID broadcast, single detection vector. Standard consumer drone.
+
+### Tips
+
+- Remote ID is mandatory for drones >250g in the US (FAA) and EU (EU 2019/945) — absence of Remote ID is itself a significant indicator
+- WiFi adapter must support monitor mode; run `airmon-ng check kill` if other processes interfere
+- The contact map only shows drones that broadcast GPS coordinates via Remote ID
+- Contacts expire after 120 seconds of inactivity — the list shows only currently active drones
+- HackRF detection is passive (receive-only); no transmission occurs
+
 ## Spy Stations
 
 1. **Browse Database** - View the full list of documented number stations and diplomatic networks

docs/index.html

@@ -36,7 +36,7 @@
             </div>
             <div class="hero-stats">
                 <div class="stat">
-                    <span class="stat-value">34</span>
+                    <span class="stat-value">35</span>
                     <span class="stat-label">Modes</span>
                 </div>
                 <div class="stat">
@@ -202,6 +202,11 @@
                         <h3>TSCM</h3>
                         <p>Counter-surveillance with baseline recording, threat detection, device correlation, and risk scoring.</p>
                     </div>
+                    <div class="feature-card" data-category="intel">
+                        <div class="feature-icon"><svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.5" stroke-linecap="round" stroke-linejoin="round"><circle cx="6" cy="6" r="2"/><circle cx="18" cy="6" r="2"/><circle cx="6" cy="18" r="2"/><circle cx="18" cy="18" r="2"/><rect x="9" y="9" width="6" height="6" rx="1"/><line x1="8" y1="8" x2="9" y2="9"/><line x1="16" y1="8" x2="15" y2="9"/><line x1="8" y1="16" x2="9" y2="15"/><line x1="16" y1="16" x2="15" y2="15"/></svg></div>
+                        <h3>Drone Intelligence</h3>
+                        <p>Multi-vector UAV detection via ASTM F3411 Remote ID (WiFi/BLE), RTL-SDR 433/868 MHz RF fingerprinting, and HackRF 2.4/5.8 GHz scanning with live contact map and risk scoring.</p>
+                    </div>
                     <div class="feature-card" data-category="wireless">
                         <div class="feature-icon"><svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.5" stroke-linecap="round" stroke-linejoin="round"><path d="M12 2L2 7l10 5 10-5-10-5z"/><path d="M2 17l10 5 10-5"/><path d="M2 12l10 5 10-5"/></svg></div>
                         <h3>Meshtastic</h3>