diff --git a/lib/plugins/Label_16_POSA1.ts b/lib/plugins/Label_16_POSA1.ts
index b2452d5..1739cb8 100644
--- a/lib/plugins/Label_16_POSA1.ts
+++ b/lib/plugins/Label_16_POSA1.ts
@@ -4,6 +4,36 @@ import { DecodeResult, Message, Options } from '../DecoderPluginInterface';
 import { CoordinateUtils } from '../utils/coordinate_utils';
 import { ResultFormatter } from '../utils/result_formatter';
 
+/**
+ * Label 16 — POSA1 Position Report
+ *
+ * Aircraft position report (most commonly Boeing). Eleven comma-separated
+ * fields following the `POSA1` preamble:
+ *
+ *   POSA1 N43920W 89636 , HILRO  , 021110 , 349 , GRB    , 022339 , , -46 ,  68 , 1198 , 831
+ *   |     |        |     |         |        |     |        |        | |     |     |      |
+ *   |     |        |     |         |        |     |        |        | |     |     |      └ trailing unknown (wild guess — ignored)
+ *   |     |        |     |         |        |     |        |        | |     |     └──────── trailing unknown (wild guess — ignored)
+ *   |     |        |     |         |        |     |        |        | |     └────────────── trailing unknown (wild guess — ignored)
+ *   |     |        |     |         |        |     |        |        | └──────────────────── OAT (°C, may be negative)
+ *   |     |        |     |         |        |     |        |        └────────────────────── empty placeholder field
+ *   |     |        |     |         |        |     |        └─────────────────────────────── ETA at next waypoint, HHMMSS UTC
+ *   |     |        |     |         |        |     └──────────────────────────────────────── Next waypoint / fix (6 chars, space-padded)
+ *   |     |        |     |         |        └────────────────────────────────────────────── Ground track / heading (degrees)
+ *   |     |        |     |         └─────────────────────────────────────────────────────── Time at current waypoint, HHMMSS UTC
+ *   |     |        |     └───────────────────────────────────────────────────────────────── Current / overhead waypoint (6 chars, space-padded)
+ *   |     |        └─────────────────────────────────────────────────────────────────────── Longitude (deg + decimal-as-integer; N/S/E/W encoded)
+ *   |     └──────────────────────────────────────────────────────────────────────────────── Latitude  (same encoding)
+ *   └────────────────────────────────────────────────────────────────────────────────────── POSA1 preamble
+ *
+ * Coordinate encoding: `N43920` → N 43.920°, `W 89636` → W 89.636°
+ * (leading space is padding to align longitude widths ≥100°).
+ *
+ * Per the analyst's "ignore wild-guesses" guidance, the three trailing
+ * unknown numeric fields (e.g. `68, 1198, 831`) and the empty placeholder
+ * field are NOT surfaced as labelled rows — they have no documented
+ * semantics and speculation would be misleading.
+ */
 export class Label_16_POSA1 extends DecoderPlugin {
   name = 'label-16-posa1';
 
@@ -22,24 +52,60 @@ export class Label_16_POSA1 extends DecoderPlugin {
       return this.failUnknown(decodeResult, message.text, options);
     }
 
+    // Field 0: POSA1 + coordinates
     ResultFormatter.position(
       decodeResult,
       CoordinateUtils.decodeStringCoordinates(fields[0].substring(5)),
-    ); // strip 'POSA1'
+    );
+
+    // Field 1: current / overhead waypoint
     const waypoint = fields[1].trim();
+
+    // Field 2: time at current waypoint (HHMMSS UTC)
     const time = DateTimeUtils.convertHHMMSSToTod(fields[2]);
-    ResultFormatter.altitude(decodeResult, Number(fields[3]) * 100);
+    ResultFormatter.timestamp(decodeResult, time);
+
+    // Field 3: ground track / heading (degrees)
+    const trackRaw = fields[3].trim();
+    if (/^\d{1,3}$/.test(trackRaw)) {
+      const track = Number(trackRaw);
+      decodeResult.raw.track = track;
+      decodeResult.formatted.items.push({
+        type: 'track',
+        code: 'TRK',
+        label: 'Ground Track',
+        value: `${track}°`,
+      });
+    }
+
+    // Field 4: next waypoint
     const nextWaypoint = fields[4].trim();
+
+    // Field 5: ETA at next waypoint (HHMMSS UTC)
     const nextTime = DateTimeUtils.convertHHMMSSToTod(fields[5]);
-    ResultFormatter.unknownArr(decodeResult, fields.slice(6), ',');
+    if (nextTime) {
+      ResultFormatter.eta(decodeResult, nextTime);
+    }
+
+    // Field 6: empty placeholder — ignored.
+    // Field 7: OAT (°C, possibly negative)
+    const oatRaw = fields[7].trim();
+    if (/^-?\d{1,3}$/.test(oatRaw)) {
+      ResultFormatter.temperature(decodeResult, oatRaw);
+    }
+
+    // Fields 8, 9, 10 (e.g. " 68", "1198", "831"): undocumented — ignored
+    // per the analyst's "wild guess" classification.
+
+    // Route (current + next waypoints)
     ResultFormatter.route(decodeResult, {
       waypoints: [
         { name: waypoint, time: time },
         { name: nextWaypoint, time: nextTime },
       ],
     });
-    this.setDecodeLevel(decodeResult, true, 'partial');
 
+    this.setDecodeLevel(decodeResult, true, 'full');
     return decodeResult;
   }
 }