diff --git a/docs/en/peripherals/adsb_flarm.md b/docs/en/peripherals/adsb_flarm.md
index 802f197e82..f8773d3555 100644
--- a/docs/en/peripherals/adsb_flarm.md
+++ b/docs/en/peripherals/adsb_flarm.md
@@ -73,11 +73,28 @@ Configure the action when there is a potential collision using the parameter bel
 
 | Parameter                                                                                                   | Description                                                                                                                                                                       |
 | ----------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
-| <a id="NAV_TRAFF_AVOID"></a>[NAV_TRAFF_AVOID](../advanced_config/parameter_reference.md#NAV_TRAFF_AVOID)    | Enable traffic avoidance mode specify avoidance response. 0: Disable, 1: Warn only, 2: Return mode, 3: Land mode.                                                                 |
-| <a id="NAV_TRAFF_A_HOR"></a>[NAV_TRAFF_A_HOR](../advanced_config/parameter_reference.md#NAV_TRAFF_A_HOR)    | Horizonal radius of cylinder around the vehicle that defines its airspace (i.e. the airspace in the ground plane).                                                                |
-| <a id="NAV_TRAFF_A_VER"></a>[NAV_TRAFF_A_VER](../advanced_config/parameter_reference.md#NAV_TRAFF_A_VER)    | Vertical height above and below vehicle of the cylinder that defines its airspace (also see [NAV_TRAFF_A_HOR](#NAV_TRAFF_A_HOR)).                                                 |
+| <a id="NAV_TRAFF_AVOID"></a>[NAV_TRAFF_AVOID](../advanced_config/parameter_reference.md#NAV_TRAFF_AVOID)    | Enable traffic avoidance mode specify avoidance response. 0: Disable, 1: Warn only, 2: Return mode, 3: Land mode.                                                                |
+| <a id="NAV_TRAFF_A_HOR"></a>[NAV_TRAFF_A_HOR](../advanced_config/parameter_reference.md#NAV_TRAFF_A_HOR)    | Horizonal radius of cylinder around the vehicle that defines its airspace (i.e. the airspace in the ground plane).                                                               |
+| <a id="NAV_TRAFF_A_VER"></a>[NAV_TRAFF_A_VER](../advanced_config/parameter_reference.md#NAV_TRAFF_A_VER)    | Vertical height above and below vehicle of the cylinder that defines its airspace (also see [NAV_TRAFF_A_HOR](#NAV_TRAFF_A_HOR)).                                                |
 | <a id="NAV_TRAFF_COLL_T"></a>[NAV_TRAFF_COLL_T](../advanced_config/parameter_reference.md#NAV_TRAFF_COLL_T) | Collision time threshold. Avoidance will trigger if the estimated time until collision drops below this value (the estimated time is based on relative speed of traffic and UAV). |
 
+### Arming Check
+
+PX4 can be configured to check for the presence of a traffic avoidance system (ADSB or FLARM transponder) before arming.
+This ensures that a traffic avoidance system is connected and functioning before flight.
+
+The check is configured using the [COM_ARM_TRAFF](../advanced_config/parameter_reference.md#COM_ARM_TRAFF) parameter:
+
+| Value | Description                                                                                                                 |
+| ----- | --------------------------------------------------------------------------------------------------------------------------- |
+| 0     | Disabled (default). No check is performed.                                                                                  |
+| 1     | Warning only. A warning is issued if no traffic avoidance system is detected, but arming is allowed.                       |
+| 2     | Enforce for all modes. Arming is denied if no traffic avoidance system is detected, regardless of flight mode.             |
+| 3     | Enforce for mission modes only. Arming is denied if no traffic avoidance system is detected and a mission mode is planned. |
+
+When a traffic avoidance system is detected, the system tracks its presence with a 3-second timeout.
+If the system is lost or regained, corresponding events are logged ("Traffic avoidance system lost" / "Traffic avoidance system regained").
+
 ## Implementation
 
 ### ADSB/FLARM
diff --git a/msg/TelemetryStatus.msg b/msg/TelemetryStatus.msg
index b2b3920a36..1f5b027f4d 100644
--- a/msg/TelemetryStatus.msg
+++ b/msg/TelemetryStatus.msg
@@ -43,6 +43,7 @@ bool heartbeat_type_gcs                     # MAV_TYPE_GCS
 bool heartbeat_type_onboard_controller      # MAV_TYPE_ONBOARD_CONTROLLER
 bool heartbeat_type_gimbal                  # MAV_TYPE_GIMBAL
 bool heartbeat_type_adsb                    # MAV_TYPE_ADSB
+bool heartbeat_type_flarm                   # MAV_TYPE_FLARM
 bool heartbeat_type_camera                  # MAV_TYPE_CAMERA
 bool heartbeat_type_parachute               # MAV_TYPE_PARACHUTE
 bool heartbeat_type_open_drone_id           # MAV_TYPE_ODID
diff --git a/msg/px4_msgs_old/msg/VehicleStatusV1.msg b/msg/px4_msgs_old/msg/VehicleStatusV1.msg
index 185076a5d6..4724a09a22 100644
--- a/msg/px4_msgs_old/msg/VehicleStatusV1.msg
+++ b/msg/px4_msgs_old/msg/VehicleStatusV1.msg
@@ -2,14 +2,14 @@
 
 uint32 MESSAGE_VERSION = 1
 
-uint64 timestamp # time since system start (microseconds)
+uint64 timestamp # [us] Time since system start
 
-uint64 armed_time # Arming timestamp (microseconds)
-uint64 takeoff_time # Takeoff timestamp (microseconds)
+uint64 armed_time # [us] Arming timestamp
+uint64 takeoff_time # [us] Takeoff timestamp
 
 uint8 arming_state
 uint8 ARMING_STATE_DISARMED = 1
-uint8 ARMING_STATE_ARMED    = 2
+uint8 ARMING_STATE_ARMED = 2
 
 uint8 latest_arming_reason
 uint8 latest_disarming_reason
@@ -24,34 +24,34 @@ uint8 ARM_DISARM_REASON_KILL_SWITCH = 8
 uint8 ARM_DISARM_REASON_RC_BUTTON = 13
 uint8 ARM_DISARM_REASON_FAILSAFE = 14
 
-uint64 nav_state_timestamp # time when current nav_state activated
+uint64 nav_state_timestamp # Time when current nav_state activated
 
-uint8 nav_state_user_intention                  # Mode that the user selected (might be different from nav_state in a failsafe situation)
+uint8 nav_state_user_intention # Mode that the user selected (might be different from nav_state in a failsafe situation)
 
-uint8 nav_state                                 # Currently active mode
-uint8 NAVIGATION_STATE_MANUAL = 0               # Manual mode
-uint8 NAVIGATION_STATE_ALTCTL = 1               # Altitude control mode
-uint8 NAVIGATION_STATE_POSCTL = 2               # Position control mode
-uint8 NAVIGATION_STATE_AUTO_MISSION = 3         # Auto mission mode
-uint8 NAVIGATION_STATE_AUTO_LOITER = 4          # Auto loiter mode
-uint8 NAVIGATION_STATE_AUTO_RTL = 5             # Auto return to launch mode
+uint8 nav_state # [@enum NAVIGATION_STATE] Currently active mode
+uint8 NAVIGATION_STATE_MANUAL = 0 # Manual mode
+uint8 NAVIGATION_STATE_ALTCTL = 1 # Altitude control mode
+uint8 NAVIGATION_STATE_POSCTL = 2 # Position control mode
+uint8 NAVIGATION_STATE_AUTO_MISSION = 3 # Auto mission mode
+uint8 NAVIGATION_STATE_AUTO_LOITER = 4 # Auto loiter mode
+uint8 NAVIGATION_STATE_AUTO_RTL = 5 # Auto return to launch mode
 uint8 NAVIGATION_STATE_POSITION_SLOW = 6
 uint8 NAVIGATION_STATE_FREE5 = 7
-uint8 NAVIGATION_STATE_ALTITUDE_CRUISE = 8      # Altitude with Cruise mode
+uint8 NAVIGATION_STATE_ALTITUDE_CRUISE = 8 # Altitude with Cruise mode
 uint8 NAVIGATION_STATE_FREE3 = 9
-uint8 NAVIGATION_STATE_ACRO = 10                # Acro mode
+uint8 NAVIGATION_STATE_ACRO = 10 # Acro mode
 uint8 NAVIGATION_STATE_FREE2 = 11
-uint8 NAVIGATION_STATE_DESCEND = 12             # Descend mode (no position control)
-uint8 NAVIGATION_STATE_TERMINATION = 13         # Termination mode
+uint8 NAVIGATION_STATE_DESCEND = 12 # Descend mode (no position control)
+uint8 NAVIGATION_STATE_TERMINATION = 13 # Termination mode
 uint8 NAVIGATION_STATE_OFFBOARD = 14
-uint8 NAVIGATION_STATE_STAB = 15                # Stabilized mode
+uint8 NAVIGATION_STATE_STAB = 15 # Stabilized mode
 uint8 NAVIGATION_STATE_FREE1 = 16
-uint8 NAVIGATION_STATE_AUTO_TAKEOFF = 17        # Takeoff
-uint8 NAVIGATION_STATE_AUTO_LAND = 18           # Land
-uint8 NAVIGATION_STATE_AUTO_FOLLOW_TARGET = 19  # Auto Follow
-uint8 NAVIGATION_STATE_AUTO_PRECLAND = 20       # Precision land with landing target
-uint8 NAVIGATION_STATE_ORBIT = 21               # Orbit in a circle
-uint8 NAVIGATION_STATE_AUTO_VTOL_TAKEOFF = 22   # Takeoff, transition, establish loiter
+uint8 NAVIGATION_STATE_AUTO_TAKEOFF = 17 # Takeoff
+uint8 NAVIGATION_STATE_AUTO_LAND = 18 # Land
+uint8 NAVIGATION_STATE_AUTO_FOLLOW_TARGET = 19 # Auto Follow
+uint8 NAVIGATION_STATE_AUTO_PRECLAND = 20 # Precision land with landing target
+uint8 NAVIGATION_STATE_ORBIT = 21 # Orbit in a circle
+uint8 NAVIGATION_STATE_AUTO_VTOL_TAKEOFF = 22 # Takeoff, transition, establish loiter
 uint8 NAVIGATION_STATE_EXTERNAL1 = 23
 uint8 NAVIGATION_STATE_EXTERNAL2 = 24
 uint8 NAVIGATION_STATE_EXTERNAL3 = 25
@@ -62,29 +62,29 @@ uint8 NAVIGATION_STATE_EXTERNAL7 = 29
 uint8 NAVIGATION_STATE_EXTERNAL8 = 30
 uint8 NAVIGATION_STATE_MAX = 31
 
-uint8 executor_in_charge                        # Current mode executor in charge (0=Autopilot)
+uint8 executor_in_charge # [-] Current mode executor in charge (0=Autopilot)
 
-uint32 valid_nav_states_mask                    # Bitmask for all valid nav_state values
-uint32 can_set_nav_states_mask                  # Bitmask for all modes that a user can select
+uint32 valid_nav_states_mask # [-] Bitmask for all valid nav_state values
+uint32 can_set_nav_states_mask # [-] Bitmask for all modes that a user can select
 
 # Bitmask of detected failures
-uint16 failure_detector_status
+uint16 failure_detector_status # [@enum FAILURE]
 uint16 FAILURE_NONE = 0
-uint16 FAILURE_ROLL = 1              # (1 << 0)
-uint16 FAILURE_PITCH = 2             # (1 << 1)
-uint16 FAILURE_ALT = 4               # (1 << 2)
-uint16 FAILURE_EXT = 8               # (1 << 3)
-uint16 FAILURE_ARM_ESC = 16          # (1 << 4)
-uint16 FAILURE_BATTERY = 32          # (1 << 5)
-uint16 FAILURE_IMBALANCED_PROP = 64  # (1 << 6)
-uint16 FAILURE_MOTOR = 128           # (1 << 7)
+uint16 FAILURE_ROLL = 1 # (1 << 0)
+uint16 FAILURE_PITCH = 2 # (1 << 1)
+uint16 FAILURE_ALT = 4 # (1 << 2)
+uint16 FAILURE_EXT = 8 # (1 << 3)
+uint16 FAILURE_ARM_ESC = 16 # (1 << 4)
+uint16 FAILURE_BATTERY = 32 # (1 << 5)
+uint16 FAILURE_IMBALANCED_PROP = 64 # (1 << 6)
+uint16 FAILURE_MOTOR = 128 # (1 << 7)
 
-uint8 hil_state
+uint8 hil_state # [enum HIL_STATE]
 uint8 HIL_STATE_OFF = 0
 uint8 HIL_STATE_ON = 1
 
 # Current vehicle locomotion method. A vehicle can have different methods (e.g. VTOL transitions from RW to FW method)
-uint8 vehicle_type
+uint8 vehicle_type # [@enum VEHICLE_TYPE]
 uint8 VEHICLE_TYPE_UNSPECIFIED = 0
 uint8 VEHICLE_TYPE_ROTARY_WING = 1
 uint8 VEHICLE_TYPE_FIXED_WING = 2
@@ -96,29 +96,29 @@ uint8 FAILSAFE_DEFER_STATE_WOULD_FAILSAFE = 2 # Failsafes deferred, but would tr
 
 bool failsafe # true if system is in failsafe state (e.g.:RTL, Hover, Terminate, ...)
 bool failsafe_and_user_took_over # true if system is in failsafe state but the user took over control
-uint8 failsafe_defer_state # one of FAILSAFE_DEFER_STATE_*
+uint8 failsafe_defer_state # [@enum FAILSAFE_DEFER_STATE]
 
 # Link loss
-bool gcs_connection_lost              # datalink to GCS lost
-uint8 gcs_connection_lost_counter     # counts unique GCS connection lost events
+bool gcs_connection_lost # datalink to GCS lost
+uint8 gcs_connection_lost_counter # counts unique GCS connection lost events
 bool high_latency_data_link_lost # Set to true if the high latency data link (eg. RockBlock Iridium 9603 telemetry module) is lost
 
 # VTOL flags
-bool is_vtol             # True if the system is VTOL capable
-bool is_vtol_tailsitter  # True if the system performs a 90° pitch down rotation during transition from MC to FW
-bool in_transition_mode  # True if VTOL is doing a transition
+bool is_vtol # True if the system is VTOL capable
+bool is_vtol_tailsitter # True if the system performs a 90° pitch down rotation during transition from MC to FW
+bool in_transition_mode # True if VTOL is doing a transition
 bool in_transition_to_fw # True if VTOL is doing a transition from MC to FW
 
 # MAVLink identification
-uint8 system_type  # system type, contains mavlink MAV_TYPE
-uint8 system_id	   # system id, contains MAVLink's system ID field
+uint8 system_type # system type, contains mavlink MAV_TYPE
+uint8 system_id # system id, contains MAVLink's system ID field
 uint8 component_id # subsystem / component id, contains MAVLink's component ID field
 
 bool safety_button_available # Set to true if a safety button is connected
 bool safety_off # Set to true if safety is off
 
-bool power_input_valid                            # set if input power is valid
-bool usb_connected                                # set to true (never cleared) once telemetry received from usb link
+bool power_input_valid # Set if input power is valid
+bool usb_connected # Set to true (never cleared) once telemetry received from usb link
 
 bool open_drone_id_system_present
 bool open_drone_id_system_healthy
@@ -129,4 +129,4 @@ bool parachute_system_healthy
 bool rc_calibration_in_progress
 bool calibration_enabled
 
-bool pre_flight_checks_pass		# true if all checks necessary to arm pass
+bool pre_flight_checks_pass # true if all checks necessary to arm pass
diff --git a/msg/translation_node/translations/translation_vehicle_status_v2.h b/msg/translation_node/translations/translation_vehicle_status_v2.h
index 926ade4da3..da4b315566 100644
--- a/msg/translation_node/translations/translation_vehicle_status_v2.h
+++ b/msg/translation_node/translations/translation_vehicle_status_v2.h
@@ -1,5 +1,5 @@
 /****************************************************************************
- * Copyright (c) 2025 PX4 Development Team.
+ * Copyright (c) 2026 PX4 Development Team.
  * SPDX-License-Identifier: BSD-3-Clause
  ****************************************************************************/
 #pragma once
@@ -19,6 +19,7 @@ public:
 	static constexpr const char* kTopic = "fmu/out/vehicle_status";
 
 	static void fromOlder(const MessageOlder &msg_older, MessageNewer &msg_newer) {
+		// Set msg_newer from msg_older
 		msg_newer.timestamp = msg_older.timestamp;
 		msg_newer.armed_time = msg_older.armed_time;
 		msg_newer.takeoff_time = msg_older.takeoff_time;
@@ -56,13 +57,14 @@ public:
 		msg_newer.open_drone_id_system_healthy = msg_older.open_drone_id_system_healthy;
 		msg_newer.parachute_system_present = msg_older.parachute_system_present;
 		msg_newer.parachute_system_healthy = msg_older.parachute_system_healthy;
+		msg_newer.traffic_avoidance_system_present = false; // New field, default to false
 		msg_newer.rc_calibration_in_progress = msg_older.rc_calibration_in_progress;
 		msg_newer.calibration_enabled = msg_older.calibration_enabled;
 		msg_newer.pre_flight_checks_pass = msg_older.pre_flight_checks_pass;
 	}
 
 	static void toOlder(const MessageNewer &msg_newer, MessageOlder &msg_older) {
-		// copy everything except the new executor_nav_state
+		// Set msg_older from msg_newer
 		msg_older.timestamp = msg_newer.timestamp;
 		msg_older.armed_time = msg_newer.armed_time;
 		msg_older.takeoff_time = msg_newer.takeoff_time;
@@ -73,6 +75,7 @@ public:
 		msg_older.nav_state_user_intention = msg_newer.nav_state_user_intention;
 		msg_older.nav_state = msg_newer.nav_state;
 		msg_older.executor_in_charge = msg_newer.executor_in_charge;
+		// nav_state_display dropped (not in V1)
 		msg_older.valid_nav_states_mask = msg_newer.valid_nav_states_mask;
 		msg_older.can_set_nav_states_mask = msg_newer.can_set_nav_states_mask;
 		msg_older.failure_detector_status = msg_newer.failure_detector_status;
@@ -99,6 +102,7 @@ public:
 		msg_older.open_drone_id_system_healthy = msg_newer.open_drone_id_system_healthy;
 		msg_older.parachute_system_present = msg_newer.parachute_system_present;
 		msg_older.parachute_system_healthy = msg_newer.parachute_system_healthy;
+		// traffic_avoidance_system_present is dropped (not in V1)
 		msg_older.rc_calibration_in_progress = msg_newer.rc_calibration_in_progress;
 		msg_older.calibration_enabled = msg_newer.calibration_enabled;
 		msg_older.pre_flight_checks_pass = msg_newer.pre_flight_checks_pass;
diff --git a/msg/versioned/VehicleStatus.msg b/msg/versioned/VehicleStatus.msg
index 41daa384b5..3420ada11c 100644
--- a/msg/versioned/VehicleStatus.msg
+++ b/msg/versioned/VehicleStatus.msg
@@ -127,6 +127,8 @@ bool open_drone_id_system_healthy
 bool parachute_system_present
 bool parachute_system_healthy
 
+bool traffic_avoidance_system_present
+
 bool rc_calibration_in_progress
 bool calibration_enabled
 
diff --git a/src/lib/events/enums.json b/src/lib/events/enums.json
index acd73c1447..20b7d841e1 100644
--- a/src/lib/events/enums.json
+++ b/src/lib/events/enums.json
@@ -276,6 +276,10 @@
                         "1073741824": {
                             "name": "open_drone_id",
                             "description": "Open Drone ID system"
+                        },
+                        "2147483648": {
+                            "name": "traffic_avoidance",
+                            "description": "Traffic Avoidance (ADSB/FLARM)"
                         }
                     }
                 },
diff --git a/src/modules/commander/Commander.cpp b/src/modules/commander/Commander.cpp
index a6175e9c67..0d11fa47c0 100644
--- a/src/modules/commander/Commander.cpp
+++ b/src/modules/commander/Commander.cpp
@@ -2880,6 +2880,22 @@ void Commander::dataLinkCheck()
 				_vehicle_status.open_drone_id_system_present = true;
 				_vehicle_status.open_drone_id_system_healthy = healthy;
 			}
+
+			// Traffic avoidance system (ADSB or FLARM)
+			if (telemetry.heartbeat_type_adsb || telemetry.heartbeat_type_flarm) {
+				if (_traffic_avoidance_system_lost) { // recovered
+					_traffic_avoidance_system_lost = false;
+
+					if (_datalink_last_heartbeat_traffic_avoidance_system != 0) {
+						mavlink_log_info(&_mavlink_log_pub, "Traffic avoidance system regained\t");
+						events::send(events::ID("commander_traffic_avoidance_regained"), events::Log::Info,
+							     "Traffic avoidance system regained");
+					}
+				}
+
+				_datalink_last_heartbeat_traffic_avoidance_system = telemetry.timestamp;
+				_vehicle_status.traffic_avoidance_system_present = true;
+			}
 		}
 	}
 
@@ -2931,6 +2947,16 @@ void Commander::dataLinkCheck()
 		_open_drone_id_system_lost = true;
 		_status_changed = true;
 	}
+
+	// Traffic avoidance system (ADSB/FLARM)
+	if ((hrt_elapsed_time(&_datalink_last_heartbeat_traffic_avoidance_system) > 3_s)
+	    && !_traffic_avoidance_system_lost) {
+		mavlink_log_critical(&_mavlink_log_pub, "Traffic avoidance system lost");
+		events::send(events::ID("commander_traffic_avoidance_lost"), events::Log::Critical, "Traffic avoidance system lost");
+		_vehicle_status.traffic_avoidance_system_present = false;
+		_traffic_avoidance_system_lost = true;
+		_status_changed = true;
+	}
 }
 
 void Commander::battery_status_check()
diff --git a/src/modules/commander/Commander.hpp b/src/modules/commander/Commander.hpp
index e4f0fef7ca..748fa9f858 100644
--- a/src/modules/commander/Commander.hpp
+++ b/src/modules/commander/Commander.hpp
@@ -243,6 +243,7 @@ private:
 	hrt_abstime _datalink_last_heartbeat_gcs{0};
 	hrt_abstime _datalink_last_heartbeat_onboard_controller{0};
 	hrt_abstime _datalink_last_heartbeat_parachute_system{0};
+	hrt_abstime _datalink_last_heartbeat_traffic_avoidance_system{0};
 
 	hrt_abstime _last_print_mode_reject_time{0};	///< To remember when last notification was sent
 
@@ -268,6 +269,7 @@ private:
 	bool _open_drone_id_system_lost{true};
 	bool _onboard_controller_lost{false};
 	bool _parachute_system_lost{true};
+	bool _traffic_avoidance_system_lost{true};
 
 	bool _last_overload{false};
 	bool _mode_switch_mapped{false};
diff --git a/src/modules/commander/HealthAndArmingChecks/CMakeLists.txt b/src/modules/commander/HealthAndArmingChecks/CMakeLists.txt
index d62d577ca4..b170d1d2ca 100644
--- a/src/modules/commander/HealthAndArmingChecks/CMakeLists.txt
+++ b/src/modules/commander/HealthAndArmingChecks/CMakeLists.txt
@@ -65,6 +65,7 @@ px4_add_library(health_and_arming_checks
 	checks/rcCalibrationCheck.cpp
 	checks/sdcardCheck.cpp
 	checks/systemCheck.cpp
+	checks/trafficAvoidanceCheck.cpp
 	checks/vtolCheck.cpp
 	checks/windCheck.cpp
 
diff --git a/src/modules/commander/HealthAndArmingChecks/HealthAndArmingChecks.hpp b/src/modules/commander/HealthAndArmingChecks/HealthAndArmingChecks.hpp
index d4f7136f1d..1986e55e15 100644
--- a/src/modules/commander/HealthAndArmingChecks/HealthAndArmingChecks.hpp
+++ b/src/modules/commander/HealthAndArmingChecks/HealthAndArmingChecks.hpp
@@ -72,6 +72,7 @@
 #include "checks/vtolCheck.hpp"
 #include "checks/offboardCheck.hpp"
 #include "checks/openDroneIDCheck.hpp"
+#include "checks/trafficAvoidanceCheck.hpp"
 #include "checks/externalChecks.hpp"
 
 class HealthAndArmingChecks : public ModuleParams
@@ -157,6 +158,7 @@ private:
 	RcAndDataLinkChecks _rc_and_data_link_checks;
 	VtolChecks _vtol_checks;
 	OffboardChecks _offboard_checks;
+	TrafficAvoidanceChecks _traffic_avoidance_checks;
 #ifndef CONSTRAINED_FLASH
 	ExternalChecks _external_checks;
 #endif
@@ -197,5 +199,6 @@ private:
 		&_flight_time_checks,
 		&_rc_and_data_link_checks,
 		&_vtol_checks,
+		&_traffic_avoidance_checks,
 	};
 };
diff --git a/src/modules/commander/HealthAndArmingChecks/checks/trafficAvoidanceCheck.cpp b/src/modules/commander/HealthAndArmingChecks/checks/trafficAvoidanceCheck.cpp
new file mode 100644
index 0000000000..baba01fd18
--- /dev/null
+++ b/src/modules/commander/HealthAndArmingChecks/checks/trafficAvoidanceCheck.cpp
@@ -0,0 +1,71 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2026 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+#include "trafficAvoidanceCheck.hpp"
+
+
+void TrafficAvoidanceChecks::checkAndReport(const Context &context, Report &reporter)
+{
+	NavModes affected_modes{NavModes::None}; // COM_ARM_TRAFF 1 - warning only, arming allowed, affected_modes stays None
+
+	switch (_param_com_arm_traff.get()) {
+	case 0:
+		return; // Check disabled
+
+	case 2:
+		affected_modes = NavModes::All; // Disallow arming for all modes
+		break;
+
+	case 3:
+		affected_modes = NavModes::Mission; // Disallow arming for mission
+		break;
+	}
+
+	if (!context.status().traffic_avoidance_system_present) {
+		/* EVENT
+		 * @description
+		 * Traffic avoidance system (ADSB/FLARM) failed to report. Make sure it is setup and connected properly.
+		 *
+		 * <profile name="dev">
+		 * This check can be configured via <param>COM_ARM_TRAFF</param> parameter.
+		 * </profile>
+		 */
+		reporter.armingCheckFailure(affected_modes, health_component_t::traffic_avoidance,
+					    events::ID("check_traffic_avoidance_missing"),
+					    events::Log::Error, "Traffic avoidance system missing");
+
+		if (reporter.mavlink_log_pub()) {
+			mavlink_log_critical(reporter.mavlink_log_pub(), "Preflight Fail: Traffic avoidance system missing");
+		}
+	}
+}
diff --git a/src/modules/commander/HealthAndArmingChecks/checks/trafficAvoidanceCheck.hpp b/src/modules/commander/HealthAndArmingChecks/checks/trafficAvoidanceCheck.hpp
new file mode 100644
index 0000000000..f34faba6fc
--- /dev/null
+++ b/src/modules/commander/HealthAndArmingChecks/checks/trafficAvoidanceCheck.hpp
@@ -0,0 +1,50 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2026 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+#pragma once
+
+#include "../Common.hpp"
+
+class TrafficAvoidanceChecks : public HealthAndArmingCheckBase
+{
+public:
+	TrafficAvoidanceChecks() = default;
+	~TrafficAvoidanceChecks() = default;
+
+	void checkAndReport(const Context &context, Report &reporter) override;
+
+private:
+	DEFINE_PARAMETERS_CUSTOM_PARENT(HealthAndArmingCheckBase,
+					(ParamInt<px4::params::COM_ARM_TRAFF>) _param_com_arm_traff
+				       )
+};
diff --git a/src/modules/commander/commander_params.c b/src/modules/commander/commander_params.c
index eb3c2109e4..ed762fd40c 100644
--- a/src/modules/commander/commander_params.c
+++ b/src/modules/commander/commander_params.c
@@ -836,6 +836,21 @@ PARAM_DEFINE_INT32(COM_ARM_HFLT_CHK, 1);
  */
 PARAM_DEFINE_INT32(COM_ARM_ODID, 0);
 
+/**
+ * Enable Traffic Avoidance system detection check
+ *
+ * This check detects if a traffic avoidance system (ADSB/FLARM transponder)
+ * is missing. Depending on the value of the parameter, the check can be
+ * disabled, warn only, or deny arming.
+ *
+ * @group Commander
+ * @value 0 Disabled
+ * @value 1 Warning only
+ * @value 2 Enforce for all modes
+ * @value 3 Enforce for mission modes only
+ */
+PARAM_DEFINE_INT32(COM_ARM_TRAFF, 0);
+
 /**
  * Enforced delay between arming and further navigation
  *
diff --git a/src/modules/mavlink/mavlink_receiver.cpp b/src/modules/mavlink/mavlink_receiver.cpp
index d34074cba2..41eaf4a355 100644
--- a/src/modules/mavlink/mavlink_receiver.cpp
+++ b/src/modules/mavlink/mavlink_receiver.cpp
@@ -2177,6 +2177,10 @@ MavlinkReceiver::handle_message_heartbeat(mavlink_message_t *msg)
 				_heartbeat_type_adsb = now;
 				break;
 
+			case MAV_TYPE_FLARM:
+				_heartbeat_type_flarm = now;
+				break;
+
 			case MAV_TYPE_CAMERA:
 				_heartbeat_type_camera = now;
 				camera_status.timestamp = now;
@@ -2925,6 +2929,7 @@ void MavlinkReceiver::CheckHeartbeats(const hrt_abstime &t, bool force)
 		tstatus.heartbeat_type_onboard_controller      = (t <= TIMEOUT + _heartbeat_type_onboard_controller);
 		tstatus.heartbeat_type_gimbal                  = (t <= TIMEOUT + _heartbeat_type_gimbal);
 		tstatus.heartbeat_type_adsb                    = (t <= TIMEOUT + _heartbeat_type_adsb);
+		tstatus.heartbeat_type_flarm                   = (t <= TIMEOUT + _heartbeat_type_flarm);
 		tstatus.heartbeat_type_camera                  = (t <= TIMEOUT + _heartbeat_type_camera);
 		tstatus.heartbeat_type_parachute               = (t <= TIMEOUT + _heartbeat_type_parachute);
 		tstatus.heartbeat_type_open_drone_id           = (t <= TIMEOUT + _heartbeat_type_open_drone_id);
diff --git a/src/modules/mavlink/mavlink_receiver.h b/src/modules/mavlink/mavlink_receiver.h
index 5023c7a7df..50a38a8c1a 100644
--- a/src/modules/mavlink/mavlink_receiver.h
+++ b/src/modules/mavlink/mavlink_receiver.h
@@ -391,6 +391,7 @@ private:
 	hrt_abstime _heartbeat_type_onboard_controller{0};
 	hrt_abstime _heartbeat_type_gimbal{0};
 	hrt_abstime _heartbeat_type_adsb{0};
+	hrt_abstime _heartbeat_type_flarm{0};
 	hrt_abstime _heartbeat_type_camera{0};
 	hrt_abstime _heartbeat_type_parachute{0};
 	hrt_abstime _heartbeat_type_open_drone_id{0};