diff --git a/target_simulator/core/models.py b/target_simulator/core/models.py
index a9ab439..276179c 100644
--- a/target_simulator/core/models.py
+++ b/target_simulator/core/models.py
@@ -11,7 +11,9 @@ from typing import Dict, List, Optional, Tuple
 
 # --- Constants ---
 MIN_TARGET_ID = 0
-MAX_TARGET_ID = 15
+# Increase allowed max target id to 32 (inclusive). Historically this was 15
+# but RIS/firmware can address up to 32 targets in current deployments.
+MAX_TARGET_ID = 32
 KNOTS_TO_FPS = 1.68781
 FPS_TO_KNOTS = 1 / KNOTS_TO_FPS
 NM_TO_FT = 6076.12
diff --git a/target_simulator/gui/payload_router.py b/target_simulator/gui/payload_router.py
index d576259..a84b508 100644
--- a/target_simulator/gui/payload_router.py
+++ b/target_simulator/gui/payload_router.py
@@ -16,7 +16,7 @@ import json
 import ctypes
 import time
 from queue import Queue, Full
-from typing import Dict, Optional, Any, List, Callable
+from typing import Dict, Optional, Any, List, Callable, Tuple
 
 from target_simulator.core.sfp_structures import SFPHeader, SfpRisStatusPayload
 from target_simulator.analysis.simulation_state_hub import SimulationStateHub
@@ -100,8 +100,14 @@ class DebugPayloadRouter:
         with self._lock:
             self._latest_payloads[flow_id] = payload
 
-    def _parse_ris_payload_to_targets(self, payload: bytearray) -> List[Target]:
-        targets = []
+    def _parse_ris_payload_to_targets(self, payload: bytearray) -> Tuple[List[Target], List[int]]:
+        """
+        Parse RIS payload and return a tuple:
+        - list of Target objects for entries with flags != 0 (active targets)
+        - list of integer target IDs present with flags == 0 (inactive)
+        """
+        targets: List[Target] = []
+        inactive_ids: List[int] = []
         try:
             parsed_payload = SfpRisStatusPayload.from_buffer_copy(payload)
             for i, ris_target in enumerate(parsed_payload.tgt.tgt):
@@ -140,14 +146,19 @@ class DebugPayloadRouter:
                     except (ValueError, TypeError):
                         target.current_heading_deg = 0.0
                     targets.append(target)
+                else:
+                    try:
+                        inactive_ids.append(int(i))
+                    except Exception:
+                        pass
         except Exception:
             self._logger.exception(
                 f"{self._log_prefix} Failed to parse RIS payload into Target objects."
             )
-        return targets
+        return targets, inactive_ids
 
     def _handle_ris_status(self, payload: bytearray):
-        real_targets = self._parse_ris_payload_to_targets(payload)
+        real_targets, inactive_ids = self._parse_ris_payload_to_targets(payload)
 
         if self._hub:
             try:
@@ -164,6 +175,15 @@ class DebugPayloadRouter:
                     # Non-fatal: continue even if packet recording fails
                     pass
 
+                # If payload included inactive targets (flags==0), clear their stored
+                # real data so they disappear from the PPI immediately.
+                try:
+                    for tid in (inactive_ids or []):
+                        if hasattr(self._hub, "clear_real_target_data"):
+                            self._hub.clear_real_target_data(tid)
+                except Exception:
+                    self._logger.debug("Failed to clear inactive target data in hub", exc_info=True)
+
                 # Add real states for active targets
                 for target in real_targets:
                     state_tuple = (
diff --git a/target_simulator/gui/ppi_display.py b/target_simulator/gui/ppi_display.py
index 7aa016f..26cf9d3 100644
--- a/target_simulator/gui/ppi_display.py
+++ b/target_simulator/gui/ppi_display.py
@@ -58,7 +58,8 @@ class PPIDisplay(ttk.Frame):
         self.show_sim_points_var = tk.BooleanVar(value=True)
         self.show_real_points_var = tk.BooleanVar(value=True)
         self.show_sim_trail_var = tk.BooleanVar(value=False)
-        self.show_real_trail_var = tk.BooleanVar(value=True)
+        # Default: do not show real trails unless the user enables them.
+        self.show_real_trail_var = tk.BooleanVar(value=False)
         self.canvas = None
         self._create_controls()
         self._create_plot()