> For the complete documentation index, see [llms.txt](https://docs.auterion.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.auterion.com/release-notes/flight-control/apx4-3.4/apx4-3.4.8.md).

# APX4 3.4.8

{% hint style="info" %}
Please use Auterion Mission Control 1.39 or newer with this version of APX4.
{% endhint %}

## Major additions

### General

* New VTX (Video Transmitter) driver with Tramp and SmartAudio v1/v2/v2.1 protocol support.
  * Control band, channel, frequency, power, and pit mode via parameters, RC aux channels, or CRSF MSP messages.
  * Add parameters [`VTX_BAND`](https://docs.px4.io/main/en/advanced_config/parameter_reference#VTX_BAND), [`VTX_CHANNEL`](https://docs.px4.io/main/en/advanced_config/parameter_reference#VTX_CHANNEL), [`VTX_FREQUENCY`](https://docs.px4.io/main/en/advanced_config/parameter_reference#VTX_FREQUENCY), [`VTX_POWER`](https://docs.px4.io/main/en/advanced_config/parameter_reference#VTX_POWER), [`VTX_PIT_MODE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#VTX_PIT_MODE), [`VTX_MAP_CONFIG`](https://docs.px4.io/main/en/advanced_config/parameter_reference#VTX_MAP_CONFIG), [`VTX_DEVICE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#VTX_DEVICE).
* New RC termination switch: Irreversible flight termination trigger via RC, separate from the kill switch.
  * Parachute deployment now only triggers on termination, not on kill.
  * Fixes: Motors restarting after parachute deployment when kill switch is disengaged.
* Autotune can now be triggered as a mission item via `MAV_CMD_DO_AUTOTUNE_ENABLE`. Enables autonomous tuning without RC or GCS link.
* Manual Control: Add [`COM_RC_IN_MODE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#COM_RC_IN_MODE) options to prioritize either RC or MAVLink Joystick input with automatic fallback to the other source when the prioritized one is lost.
* Logger: `SDLOG_NO_POS_DAT` only redacts position-related fields, not entire messages.
  * New value `2` redacts both global and local position.

### Fixed Wing / VTOL in Cruise

* New quaternion based fixed-wing attitude controller.
  * Replaces the previous controller based on Euler angles.
  * Eliminates singularities and improves robustness at high pitch and roll angles.

### State Estimation

* EKF2: Support simultaneous fusion of up to 4 Auxiliary Global Position (AGP) sources (e.g. visual navigation, pseudolites).
  * New per-instance parameters [`EKF2_AGP{0..3}_*`](https://docs.px4.io/main/en/advanced_config/parameter_reference#EKF2_AGP0_CTRL) replace previous `EKF2_AGP_*`.
  * MAVLink: Support for `GLOBAL_POSITION_SENSOR` message to inject auxiliary global position data into PX4 for EKF2 fusion.
* EKF2: Support simultaneous fusion of up to 2 GNSS receivers.
  * New per-instance parameters [`SENS_GPS{0,1}_ID`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SENS_GPS0_ID), [`SENS_GPS{0,1}_DELAY`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SENS_GPS0_DELAY), and [`SENS_GPS{0,1}_OFF{X,Y,Z}`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SENS_GPS0_OFFX) replace previous `EKF2_GPS_*`.
* EKF2: Add ranging beacon fusion support. Ranging beacon measurements are now parsed from MAVLink, published as a uORB message, and fused by EKF2 as a position aid source.

### Sensors, Drivers

* DShot: Support Extended DShot Telemetry (EDT)
  * Decodes ESC temperature, voltage, and current directly from BDShot frames, eliminating the need for a serial telemetry wire.
  * Enable via [`DSHOT_BIDIR_EDT`](https://docs.px4.io/main/en/advanced_config/parameter_reference#DSHOT_BIDIR_EDT) (replaces `DSHOT_BIDIR_EN`).
* 15+ new sensors and peripherals, including external INS/AHRS systems (Inertial Labs, SBG Systems, EULER-NAV), new IMUs, rangefinders, and ADCs. See the [Sensors, Drivers](#sensors-drivers-1) section below for the full list.

## What's New

### General

* RC: Add support for CRSF and ELRS link statistics messages (RSSI, link quality, SNR).
* Remote prearm safety switch control via MAVLink command.
  * Allows activating/deactivating the prearm safety system remotely from a GCS or via `commander safety on/off`.
* RTL: Add new [`RTL_TYPE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#RTL_TYPE) option (value 5) to restrict return destinations to safe points (rally points) only. Enforce at least one rally point when [`RTL_TYPE`](https://docs.px4.io/main/en/advanced_config/parameter_reference.html#RTL_TYPE) is 5.
* Failsafe: Add option to hold at position where the last heartbeat was received. Enable through new [`NAV_LTR_LAST_DL`](https://docs.px4.io/main/en/advanced_config/parameter_reference.html#NAV_LTR_LAST_DL) parameter. Failsafe action has to be set to Loiter (Hold) mode in [`NAV_DLL_ACT`](https://docs.px4.io/main/en/advanced_config/parameter_reference.html#NAV_DLL_ACT).
* Failsafe: Trigger RTL when the parachute system goes missing or unhealthy during flight. Gated by [`COM_PARACHUTE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#COM_PARACHUTE).
* Commander: New [`COM_ARM_ON_BOOT`](https://docs.px4.io/main/en/advanced_config/parameter_reference.html#COM_ARM_ON_BOOT) parameter.
  * When enabled, the vehicle automatically arms on boot once pre-flight checks pass.
  * Intended for RF-restricted areas or applications where GCS/RC arming is not possible.
* External Modes:
  * Add configuration override flag to prevent automatic home position update when an external mode executor runs land mode.
  * Add registration flag to control whether an external mode is user-selectable in the ground station. Modes intended to run only within a mode executor can now be hidden from the user.
* UAVCAN Hardpoint: Add gripper control via `MAV_CMD_DO_GRIPPER` command, supporting both mission waypoints and manual commands.

### Multicopter / VTOL in Hover

* VOXL ESC: Add [`VOXL_ESC_T_ON`](https://docs.px4.io/main/en/advanced_config/parameter_reference#VOXL_ESC_T_ON) parameter to map a MAVLink `MANUAL_CONTROL` button to turtle mode activation.

### Fixed Wing / VTOL in Cruise

* Fixed-wing Auto Launch
  * Add option to lock selected control surfaces before and during launch via [`FW_LAUN_CS_LK_DY`](https://docs.px4.io/main/en/advanced_config/parameter_reference#FW_LAUN_CS_LK_DY) and [`CA_SV_CS_LAU_LK`](https://docs.px4.io/main/en/advanced_config/parameter_reference#CA_SV_CS_LAU_LK). Useful for tube launches where surfaces cannot move until clear of the tube.
  * Add option to drive up to 3 peripheral servo channels to their maximum value after a configurable delay post-launch.
    * Configure via new `CA_TKO_PS{1..3}_CH` (channel selection) and `CA_TKO_PS{1..3}_DY` (delay in seconds) parameters.
* Configurable flap slew rate via [`CA_SV_FLAP_SLEW`](https://docs.px4.io/main/en/advanced_config/parameter_reference#CA_SV_FLAP_SLEW). Previously hard-coded to 2 seconds.

### VTOL

* ICE control module: Add option to start internal combustion engine only when in fixed-wing or transition to fixed-wing.
  * Enable with parameter [`ICE_ON_SOURCE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#ICE_ON_SOURCE).
* New ice shedding feature: Periodically spin unused MC motors during fixed-wing flight to break off ice buildup.
  * Configured via [`CA_ICE_PERIOD`](https://docs.px4.io/main/en/advanced_config/parameter_reference#CA_ICE_PERIOD) (disabled by default).
  * [Documentation](https://docs.px4.io/main/en/config_vtol/vtol_ice_shedding).

### Rover

* Rover: Add exponential and super-exponential stick input curve for yaw rate control.
  * New parameters: [`RO_YAW_EXPO`](https://docs.px4.io/main/en/advanced_config/parameter_reference#RO_YAW_EXPO), [`RO_YAW_SUPEXPO`](https://docs.px4.io/main/en/advanced_config/parameter_reference#RO_YAW_SUPEXPO), [`RD_YAW_STK_GAIN`](https://docs.px4.io/main/en/advanced_config/parameter_reference#RD_YAW_STK_GAIN), [`RM_YAW_STK_GAIN`](https://docs.px4.io/main/en/advanced_config/parameter_reference#RM_YAW_STK_GAIN).

### State Estimation

* EKF2: Add MAVLink-based runtime sensor fusion control via `VEHICLE_CMD_SET_EKF_SENSOR_FUSION`.
  * New [`EKF2_SENS_EN`](https://docs.px4.io/main/en/advanced_config/parameter_reference.html#EKF2_SENS_EN) bitmask parameter enables or disables individual fusion sources, applied on disarm.
  * New `ESTIMATOR_SENSOR_FUSION_STATUS` MAVLink stream reports the intended and active fusion state.
* EKF2: Add low-earth-orbit (LEO) satellite systems as a supported global position source in `AuxGlobalPosition` and `GLOBAL_POSITION_SENSOR` MAVLink message.
* EKF2: Add PPS (Pulse Per Second) time correction for GNSS measurements.
  * If available, the measured delay is used rather than the parameter [`EKF2_GPS_DELAY`](https://docs.px4.io/main/en/advanced_config/parameter_reference#EKF2_GPS_DELAY).
  * Add [`PPS_CAP_GPS_ID`](https://docs.px4.io/main/en/advanced_config/parameter_reference#PPS_CAP_GPS_ID) parameter to select which GNSS receiver is used for PPS timestamp correlation by device ID. Enables reliable PPS in multi-GNSS setups.
  * [Documentation](https://docs.px4.io/main/en/advanced/pps_time_sync).
* EKF2: Add GNSS jamming detection and handling to preflight and in-flight health checks, similar to existing spoofing detection.
  * Configure with new Jamming bit in [`EKF2_GPS_CHECK`](https://docs.px4.io/main/en/advanced_config/parameter_reference#EKF2_GPS_CHECK).
* EKF2: Add parameter [`EKF2_ENGINE_WRM`](https://docs.px4.io/main/en/advanced_config/parameter_reference#EKF2_ENGINE_WRM) to enable constant position fusion during engine warm-up (to avoid estimation issues due to vibration).
* EKF2: Add parameter [`EKF2_REQ_FIX`](https://docs.px4.io/main/en/advanced_config/parameter_reference#EKF2_REQ_FIX) parameter sets the minimum required GNSS fix type (e.g. RTK) before arming.
* EKF2: Add support for manual heading reset via `MAV_CMD_EXTERNAL_ATTITUDE_ESTIMATE` or `commander set_heading`.

### Sensors, Drivers

* Multi-instance heater support for independent temperature control of multiple IMUs.
  * New parameters: [`HEATER{1..3}_IMU_ID`](https://docs.px4.io/main/en/advanced_config/parameter_reference#HEATER1_IMU_ID), [`HEATER{1..3}_TEMP`](https://docs.px4.io/main/en/advanced_config/parameter_reference#HEATER1_TEMP), [`HEATER{1..3}_TEMP_{P,I,FF}`](https://docs.px4.io/main/en/advanced_config/parameter_reference#HEATER1_TEMP_FF).
  * Remove previous single-instance parameters `HEATER_IMU_ID` etc.
* Battery: Add configurable low-pass filter time constants for analog battery voltage ([`BAT{1..3}_V_FILT`](https://docs.px4.io/main/en/advanced_config/parameter_reference#BAT1_V_FILT)) and current ([`BAT{1..3}_I_FILT`](https://docs.px4.io/main/en/advanced_config/parameter_reference#BAT1_I_FILT)) ADC readings to reduce noise.
* DShot: AM32 ESC EEPROM read/write support via MAVLink. Configure ESC settings directly from the ground station. Requires [`DSHOT_ESC_TYPE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#DSHOT_ESC_TYPE) set to AM32.
* New u-blox GNSS driver features:
  * Add jamming detection sensitivity parameter [`GPS_UBX_JAM_DET`](https://docs.px4.io/main/en/advanced_config/parameter_reference#GPS_UBX_JAM_DET).
  * Add configurable measurement output rate parameter [`GPS_UBX_RATE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#GPS_UBX_RATE) and autobauding support.
  * Expose parameters [`GPS_UBX_MIN_CNO`](https://docs.px4.io/main/en/advanced_config/parameter_reference#GPS_UBX_MIN_CN0), [`GPS_UBX_MIN_ELEV`](https://docs.px4.io/main/en/advanced_config/parameter_reference#GPS_UBX_MIN_ELEV), and [`GPS_UBX_DGNSS_TO`](https://docs.px4.io/main/en/advanced_config/parameter_reference#GPS_UBX_DGNSS_TO)
* UAVCAN
  * Add device information tracking, publishing firmware/hardware version, serial number, and vendor/model for all attached UAVCAN devices. Logged in `device_information` message.
  * GNSS: Extend [`SENS_GPS_PRIME`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SENS_GPS_PRIME) to support selecting a primary GNSS among UAVCAN GNSS modules by node ID.
  * Add `CANNODE_NODE_ID` parameter for setting a static node ID on CAN nodes.
  * Add `CANNODE_PUB_BAR` and `CANNODE_PUB_MAG` parameters to optionally disable barometer and magnetometer data publication on CAN nodes.
  * Node: Add hardpoint command support. CAN nodes can now receive and handle hardpoint commands in addition to servo and motor array commands.
  * Configurable LED light control with flexible addressing.
    * New parameters [`UAVCAN_LGT_NUM`](https://docs.px4.io/main/en/advanced_config/parameter_reference#UAVCAN_LGT_NUM), [`UAVCAN_LGT_ID{0..15}`](https://docs.px4.io/main/en/advanced_config/parameter_reference#UAVCAN_LGT_ID0), and [`UAVCAN_LGT_FN{0..15}`](https://docs.px4.io/main/en/advanced_config/parameter_reference#UAVCAN_LGT_FN0) allow controlling individual LEDs on any DroneCAN peripheral (e.g. Vertiq ESCs with LED add-ons).
    * Removes `UAVCAN_LGT_STROB`, `UAVCAN_LGT_NAV`, and `UAVCAN_LGT_LAND` parameters.
* Boards: Add support for ARK X20 GNSS and ARK F9P GNSS CAN nodes.
* FMU-v6s
  * Add PCA9685 I2C PWM servo driver support with configurable I2C bus selection.
  * Add support for INA226, INA228, and INA238 digital power modules. Analog battery monitoring is automatically disabled when a digital power module is enabled.
* Support new sensors and peripherals:
  * ARK DIST CAN distance sensor node (Broadcom AFBRS50)
  * ARK MAG CAN magnetometer node (RM3100)
  * ADIS16607 IMU
  * ADS7953 16-channel ADC
  * AW2023 RGB LED
  * EULER-NAV Baro-Inertial AHRS (serial, provides attitude/IMU/baro data)
  * IST8310 magnetometer: Support IST8310J variant
  * Inertial Labs INS/AHRS/IMU
  * Lightware GRF250/GRF500 distance sensors, I2C
  * Lightware GRF250/GRF500 rangefinder (serial and I2C)
  * MCP23017 I2C GPIO expander
  * MCP9808 I2C temperature sensor
  * SBG Systems INS (sbgECom, provides IMU/GNSS/EKF data)
  * TLA2528 I2C ADC
  * TMP102 temperature sensor
  * Winbond W25N01GV NAND flash (128MB, littlefs, for SD-less logging)

## What Improved

### General

**Improvements**

* Manual Control: Extend [`COM_RC_IN_MODE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#COM_RC_IN_MODE) prioritization with ascending/descending instance ordering modes
  * Enables seamless failover between multiple MAVLink control sources (e.g. RC over MAVLink and C2 over LTE).
* Parameter Reset: `RC*` parameters are no longer excluded from parameter resets. RC calibration values will now be reset along with other parameters.
* Commander
  * [`COM_RCL_EXCEPT`](https://docs.px4.io/main/en/advanced_config/parameter_reference#COM_RCL_EXCEPT) bit 1 (Hold) now exempts all auto modes from manual control loss failsafe, not just Hold. Also unify manual control loss and data link exception parameter options.
  * Extend arm throttle safety check to all vehicle types including rovers, and unify throttle checks per vehicle type and control mode. Fixes: Rovers had no throttle safety check at arming.
  * Update `COM_DLL_NAV_CTL` to a bitmask supporting multiple AGP fallback modes on data-link-loss. Fully backwards compatible.
* ESC/Motor failure detection overhaul:
  * Run ESC telemetry timeout check even when disarmed.
  * Motor and ESC failures are non-latching and clear when resolved.
  * Combine `FD_ESCS_EN` into [`COM_ARM_CHK_ESCS`](https://docs.px4.io/main/en/advanced_config/parameter_reference#COM_ARM_CHK_ESCS).
  * Rename motor failure parameters from `FD_ACT_*` to [`MOTFAIL_*`](https://docs.px4.io/main/en/advanced_config/parameter_reference#MOTFAIL_THR)
* Failure Detector: Fix false motor failure reports with non-sequential ESC numbering; add overcurrent detection.
* Battery
  * Declare fault and warn user when battery/power module temperature exceeds 100 °C. Prevents potential vehicle loss from power module overheating.
  * [`BAT{1,2}_I_OVERWRITE`](https://docs.px4.io/main/en/advanced_config/parameter_reference.html#BAT1_I_OVERWRITE) parameter now applies to all battery estimation sources, not just analog.
* MAVLink: Add `PARAM_ERROR` message support. Parameter read/set errors are now reported to the GCS instead of silently failing.
* Gimbal: Increase `GIMBAL_DEVICE_ATTITUDE_STATUS` MAVLink stream rate to 50 Hz.
* Payload Board: Add joystick (MAVLink manual control) input support alongside existing RC input, via new `PB_IN_AUX` and `PB_OUT_CHANNEL` parameters.
* v5x/v6x/v6s: Switch to `COMMON_RC` driver, enabling bidirectional RC protocols like CRSF and GHST with telemetry support.
* v5x/v6x: Include PWM input driver for ATS-based flight termination.
* FMU-v6xRT: Add support for sensor set Rev 2 (BMM350 replacing BMM150) and Rev 3 (dual ICM45686 IMUs).
* FMU-v6s/v6x: Enable PPS capture input. FMU-v6s gains two additional PWM output channels (PWM9, PWM10).
* v6xRT: Add bootloader support for NXP i.MX RT1170B. Fixes: Bootloader failing to boot on v6xRT boards with the RT1170B silicon revision.

**Bugfixes**

* Commander
  * Fix PX4 freezing during gyro, accel, or mag calibration on Linux.
  * Fix incorrect mode or executor state after disarming when using external modes.
  * Fix magless setups unable to arm in modes that do not require heading (e.g. Altitude, Stabilized).
  * Fix vehicle immediately re-initiating takeoff after auto-landing, disarming, and arming again.
  * Fix home position set from raw GNSS data even when the estimator is not using GNSS, causing incorrect RTL targets.
* Navigator
  * Fixes regarding [`RTL_TYPE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#RTL_TYPE) 2 (Return to mission landing if available)
    * Fix vehicle stuck hovering when no mission is present (now falls back to Home).
    * Fix not respecting [`RTL_LAND_DELAY`](https://docs.px4.io/main/en/advanced_config/parameter_reference#RTL_LAND_DELAY).
  * Fix vehicle loitering at the wrong position after completing a mission.
  * Fix altitude setpoint dropping to zero during DELAY or DO commands in the first 120s after takeoff.
  * Fix vehicle losing its setpoint (going IDLE) during mission-based RTL when the mission contains condition gates.
  * Fix short spike of zero throttle when entering RTL with fixed-wing vehicles.
  * Fix vehicle flying to the wrong waypoint when reversing along the mission during RTL.
  * Fix mission invalidity warnings with no explanation of the cause.
* Failsafe
  * Fix vehicle terminating immediately when arming with [`NAV_DLL_ACT`](https://docs.px4.io/main/en/advanced_config/parameter_reference.html#NAV_DLL_ACT) set to Terminate.
  * Fix entering Hold mode when failsafe action is set to Warn.
  * Fix action executing immediately instead of waiting for the configured delay.
  * Fix data link loss failsafe overriding an intentional flight termination command.
  * Fix RC mode switch having no effect when the configured failsafe action fell back to a different action (e.g. RTL degraded to Land).
  * Fix brief Hold mode entry during low battery flight-time warning when [`COM_FLTT_LOW_ACT`](https://docs.px4.io/main/en/advanced_config/parameter_reference#COM_FLTT_LOW_ACT) is set to None.
  * Fix vehicle switching to Position mode on Offboard signal loss when no manual control is present.
* Mission
  * Fix vehicle pacing back and forth while waiting at a delay waypoint.
  * Fix incorrect approach behavior when the last waypoint before landing is not directly above the landing point.
* Manual Control: Fix payload power switch defaulting to ON on boot. Now defaults to OFF when [`RC_MAP_PAY_SW`](https://docs.px4.io/main/en/advanced_config/parameter_reference#RC_MAP_PAY_SW) is configured, and syncs to the actual switch position on first RC connection.
* PX4IO: Fix garbled SBUS data after RC loss causing unexpected mode switches (e.g. Mission to Hold).
* ADS-B collision avoidance: Fix incorrect detection zone when horizontal and vertical separation thresholds differ.
* Control Allocator: Fix ESCs receiving disarmed PWM without respecting the configured slew rate, caused by brief zero-thrust setpoints.
* Gimbal: Fix servo updating too slowly when the vehicle rotates.
* SIH: Fix actuator outputs locked down during Software-In-Hardware simulation, preventing actuator testing.
* ICE: Fix internal combustion engine stopping when RC is switched off.
* Battery: Fix negative discharged capacity values when current sensing is unavailable.
* Payload Board: Fix AUX channel numbering mismatch in RC channel provider.
* MAVLink
  * Fix ground station not receiving available modes over low bandwidth radio links.
  * FTP: Fix Actuator configuration and system health views not loading correctly when multiple GCS components are connected.
  * Fix USB MAVLink connection hanging when reconnecting.
  * Fix hardfault/crash when disconnecting USB comms link.
  * Fix mission failing to sync due to dropped MAVLink messages during upload.
* UAVCAN bootloader: Fix watchdog timeout when flashing firmware larger than 500kB.
* UAVCAN: Fix SD card corruption when migrating firmware files on STM32H7.
* Skynode S
  * Update LittleFS to 2.11.3 to fix sporadic FRAM filesystem corruption.
    * Fixes: Parameters and airframe data could be silently corrupted.
    * Note: downgrading to an older APX4 version after this update will erase FRAM data (parameters) on Skynode S.
  * Add support for hardware revision 1.7.1, which uses EEPROM instead of FRAM for parameter storage.
* Skynode v6n: Battery measurement now defaults to the CAN power module for improved accuracy.
* Skynode N: External voltage and current monitoring is now supported.
* ARK boards: Fix spurious motor activation when only some outputs are configured as DShot.
* Fix camera capture not working on FMU-v6x and other boards.
* Median Filter: Handle NaN values correctly in comparator. Fixes nondeterminism and instability in rangefinder fog detection, gyroscope calibration, GyroFFT notch selection, and RPM estimation.

### Multicopter / VTOL in Hover

**Bugfixes**

* Multicopter Position Control
  * Fix setpoint jump when switching from GoTo into another position mode.
  * Fix abrupt velocity zeroing when flying fast and a failsafe triggers.
  * Fix unexpected climb or drop when switching out and back into position controlled mode.
* FlightTaskAuto
  * Disable [`MPC_LAND_RADIUS`](https://docs.px4.io/main/en/advanced_config/parameter_reference#MPC_LAND_RADIUS) by default (value `-1`). Fixes unintended landing radius constraint of 1000m interfering with nudging.
  * Fix unexpected sudden direction changes during autonomous flight when far from the planned path.
* Position Slow Mode
  * Fix gimbal yaw lock persisting incorrectly after switching between Position and Position Slow mode.
  * Fix velocity not correctly limited via knob input.
* StickYaw: Fix potential large yaw jump during yaw lock in position-controlled flight modes.
* GotoControl: Fix jerky movement when switching between mission and GoTo control.
* Precision Landing: Fix incorrect search altitude when local position reference differs from home position.
* Multicopter Attitude Control: Fix heading lock in Stabilized mode when absolute heading is not yet available.

### Fixed Wing / VTOL in Cruise

**Improvements**

* Airspeed Selector
  * Fix ground-minus-wind airspeed estimate being almost never valid by increasing default [`ASPD_WERR_THR`](https://docs.px4.io/main/en/advanced_config/parameter_reference#ASPD_WERR_THR).
  * Persist estimated airspeed scale ([`ASPD_SCALE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#ASPD_SCALE)) across reboots. The scale is saved on disarm when it changes by more than 3%, allowing transfer between vehicles of the same airframe model.
* Fixed-wing Autotune
  * Fix excessively high angular rates during autotune leading to non-linear behavior and poor system identification. Maneuver amplitude is now limited automatically.
  * Continue to next axis on convergence timeout instead of aborting the entire run.
* Wind estimator: Estimate airspeed scale faster at beginning of flight, if the scale was not already estimated or provided in the airframe file. [Documentation](https://docs.px4.io/main/en/config_fw/airspeed_scale_handling#airspeed-scale-handling).
* TECS: Increase default [`FW_T_HRATE_FF`](https://docs.px4.io/main/en/advanced_config/parameter_reference.html#FW_T_HRATE_FF) from 0.3 to 0.5 for tighter altitude rate tracking, especially during landing approach.

**Bugfixes**

* Fixed-wing Autotune
  * Fix immediate failure on first activation.
  * Fix misbehavior due to incorrect timing of state transitions.
* Fixed-wing Rate Control
  * Fix jittery servo commands caused by noisy airspeed measurements.
  * Robustify gain compression against transient NaN inputs.
  * Fix yaw rate setpoints from Offboard mode being discarded unless [`FW_ACRO_YAW_EN`](https://docs.px4.io/main/en/advanced_config/parameter_reference#FW_ACRO_YAW_EN) was enabled.
* Fixed-wing Landing
  * Fix vehicle pitching down at flare initiation when descending faster than the nominal sink rate.
  * Fix circular landing not working when flying with airspeed sensor but without global position.
* RTL time estimator: Fix overly pessimistic return time estimate causing premature RTL when flying in strong headwinds.
* RTL Mission: Fix fixed-wing landing pattern veering off the expected course during RTL.
* Fix loiter direction not correctly applied when [`NAV_LOITER_RAD`](https://docs.px4.io/main/en/advanced_config/parameter_reference#NAV_LOITER_RAD) is set negative for counter-clockwise loiter.
* Fixed-wing Takeoff: Fix mode never transitioning to Hold after reaching the takeoff altitude.
* Fixed-wing Launch Detection: Fix detection failing for lateral releases, drops, or imperfect hand/catapult launches.
* Fixed-wing Mode Manager: Fix vehicle not holding altitude when entering the initial loiter before DESCEND.
* Fixed-wing Attitude Control: Fix incorrect yaw/pitch-rate response during coordinated turns.
* Fixed-wing Attitude Control: Fix stabilized mode roll setpoint exceeding [`FW_MAN_R_MAX`](https://docs.px4.io/main/en/advanced_config/parameter_reference.html#FW_MAN_R_MAX).
* Fixed-wing Land Detector: Fix unwanted control surface deflections caused by premature takeoff detection during runway roll.
* EKF2: Fix heading drifting during motor ramp-up before catapult launch.
* Airspeed calibration: Only save differential pressure offset after all checks pass. Fixes sensor status appearing green even when airspeed calibration failed.
* Airspeed selector: Fix manually changing the airspeed scale parameter during flight having no immediate effect.
* Control Allocator: Fix flaperons and spoilerons deflecting without any input, making them unusable.
* Actuators: Fix flaps not assignable to AUX input channels.
* TECS: Fix throttle not recovering after zero-throttle flight phases (e.g. on gliders).

### VTOL

**Improvements**

* VTOL Backtransition: Several improvements leading to smoother and more predictable backtransitions.
* EKF2: Fix VTOL oscillating between Land and Descend modes when hovering in strong headwinds without GNSS.
* VTOL Takeoff: Support specifying transition heading via `MAV_CMD_NAV_VTOL_TAKEOFF` param2/param4, per the MAVLink `VTOL_TRANSITION_HEADING` specification.

**Bugfixes**

* Pusher Assist: Fix discontinuous forward thrust when minimum pitch is set below zero.
* VTOL: Fix spurious fixed-wing hold at dangerously low altitude when terrain drops during GPS-denied front transition with optical flow.
* RTL Mission Fast: Fix VTOL getting stuck after back-transition.
* Navigator: Fix vehicle abandoning its horizontal trajectory (e.g. orbit) and braking to hover when changing altitude.

### Rover

**Improvements**

* Separate speed and attitude control in rover setpoint hierarchy. Speed and attitude setpoints are now independent, removing ambiguity when accessing rover setpoints through API (e.g. offboard control).
* Rover: Fix rover unexpectedly moving again at the final waypoint due to GNSS drift or position estimate resets.

**Bugfixes**

* Rover
  * Fix large setpoint jumps and erratic movement on first update after arming.
  * Fix noticeable delay in rate control for acro, stabilized, and position modes.
  * Fix motors not responding in position mode, offboard, or GoTo with default parameters.
* Mecanum Rover: Fix yaw field in offboard position commands being ignored.

### State Estimation

**Improvements**

* EKF2
  * Add [`EKF2_AGP_MODE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#EKF2_AGP_MODE) to control auxiliary global position reset behavior on fusion timeout. Also allow manual position override via `VEHICLE_CMD_EXTERNAL_POSITION_ESTIMATE` when horizontal aiding is active.
  * Introduce dead-reckoning GNSS mode ([`EKF2_GPS_MODE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#EKF2_GPS_MODE)) to avoid position jumps with spoofed or faulty GPS.
    * Pervents resetting to GNSS height when other height source is available,
    * Disables GNSS position fusion when a GNSS altitude fault is deteted.
  * Always use strict GNSS quality checks while on the ground. Previously, strict checks only had to pass once and could degrade before takeoff. Now the checks are enforced continuously until airborne.
  * Improve manual position resets
    * Reset-by-fusion: properly update wind-velocity correlation with realistic uncertainty.
    * Hard reset: Reset wind estimate to zero, with high uncertainty to allow for faster re-estimation

**Bugfixes**

* EKF2
  * Fix biased velocity estimate after airspeed fusion resumes following a long dead-reckoning period.
  * Fix magnetometer permanently disabled for the rest of the flight after a temporary magnetic disturbance.
  * Fix heading over-corrections during acceleration phases, especially in magless operation.
  * Fix arming allowed in position mode without valid heading when magnetometer fusion fails and no other heading source is present.
  * Fix heading drift contaminating position and velocity estimates when no heading sensor is active.
  * Fix wrong height estimates when using external vision in NED frame without heading.
  * Fix spurious yaw emergency reset shortly after GNSS position fusion begins after takeoff.
  * Fix yaw spikes in attitude output during EKF yaw resets.
  * Fix height reference update in conditional range aid mode. Skip unhealthy range finder samples while respecting timeout before stopping range height fusion.
  * Fix heading drift in magless operation caused by spurious corrections from gravity vector fusion.
  * Fix terrain altitude estimate getting stuck at an unrealistic value with optical flow and low sensor noise settings.
  * Fix false airspeed failures and erratic velocity estimates after heading corrections on fixed-wing aircraft.
  * Fix incorrect velocity and height data being fused during GNSS dead-reckoning mode.
  * Fix external heading reset command acknowledged but not applied when the EKF has no active yaw source.

### Sensors, Drivers

**Improvements**

* AUAV Airspeed Sensor: Fix incorrect airspeed readings when wrong pressure range is configured. The range is now read automatically from sensor EEPROM.
* Murata SCH16T IMU: Add support for new B10 and B13 modules with updated gyro range (up to 5000 °/sec) and scale.
* INA2xx power monitor: Fix spurious critical low battery warnings from a single I2C read failure.
* Auterion Power Module: Automatic shunt and max current detection via onboard EEPROM, replacing manual probing.
* GPS: Fix RTCM injection with frame-aligned parsing. Add [`GPS_UBX_PPK`](https://docs.px4.io/main/en/advanced_config/parameter_reference#GPS_UBX_PPK) parameter to enable MSM7 output for PPK workflows.
* Rangefinder: Add quaternion orientation support in `distance_sensor` messages, enabling oriented rangefinder data for collision prevention.
* Lightware Laser I2C: Add binary protocol support for SF30/d and fix SF20/c initialization. Fixes: \~1s measurement delay with SF30/d using the legacy protocol.
* Lightware SF1XX: Use [`SF1XX_ROT`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SF1XX_ROT) parameter as the single source of truth for sensor rotation, removing the -R CLI option. Update supported model list to include SF30/d, GRF250, and GRF500.
* VOXL ESC: Add open-loop PWM command mode. The UART-based ESC can now receive raw power level commands instead of only closed-loop RPM matching.
* PCA9685
  * Add configurable I2C address via [`PCA9685_I2C_ADDR`](https://docs.px4.io/main/en/advanced_config/parameter_reference#PCA9685_I2C_ADDR) parameter. Enable on additional boards (FMU-v6x, fpv, pi6x).
* DShot
  * BDShot is now selected per-timer in the actuator configuration UI. Multi-timer sequential capture enables BDShot on any DMA-capable timer, with support for up to 16 channels.
  * Per-motor pole count via [`DSHOT_MOT_POL{1..12}`](https://docs.px4.io/main/en/advanced_config/parameter_reference#DSHOT_MOT_POL1) replaces the global `MOT_POLE_COUNT` parameter.
* UAVCAN ESC: Improve ESC health monitoring with extended status messages, motor temperature reporting, and vendor-specific error parsing (IQ Motion). Update node status monitoring for better reliability.
* Magnetometer Calibration: Suppress critical warnings for sensors that are disabled.

**Bugfixes**

* Accelerometer Calibration: Rotate offsets and scales back into sensor frame before saving to fix incorrect calibration results.
* Magnetometer Calibration: Fix calibration failing in locations with stronger earth field.
* BMM350 magnetometer: Fix value offset at low temperatures.
* QMC5883P Magnetometer: Fix excessive noise causing unstable heading.
* BMP581: Fix invalid barometer samples being published when I2C data corruption occurs.
* Barometer
  * Fix incorrect temperature compensation, particularly affecting the MS5837 driver.
  * Fix offset calibration incorrectly running while in air.
* Barometer calibration: Fix `commander calibrate baro` hanging indefinitely.
* Temperature compensation: Fix calibration starting the wrong sensor (baro started gyro, mag started baro).
* DShot
  * Fix incorrect `UNSUPPORTED` response when configuring DShot motors with `MAV_CMD_CONFIGURE_ACTUATOR`.
  * Fix incorrect current values reported via ESC telemetry.
  * Fix bidirectional ESC telemetry not working on FMU-v6xRT.
  * Fix high error rates with bidirectional DShot on AM32 ESCs on FMU-v6xRT.
* DroneCAN ESC
  * Fix motors not spinning during actuator test in AMC.
  * Fix compatibility issue with some ESCs (e.g. T-Motor, Vertiq).
* UAVCAN GNSS: Fix dual-antenna GNSS receivers (e.g. Septentrio Mosaic G5) not providing heading without RTK fix.
* CRSF RC: Fix RC input processing permanently stalling until reboot on malformed frames.
* Serial
  * Fix serial port settings (byte size, flow control, parity, stop bits) not being applied on NuttX.
  * Fix RTCM injection bursts blocking GNSS read processing, causing GNSS failures.
* GPS
  * Fix RTK dropouts on ARK X20.
  * Fix GNSS timestamp always reported as 0.
  * Report jamming detection as a Warning instead of Critical.
* SF45 Lidar: Fix all distance bins reporting invalid values instead of actual measurements.
* VectorNav: Fix global position data from VectorNav INS not being used.
* ESC: Fix false motor failure detection with ESC drivers that have longer polling intervals (e.g., VOXL, UAVCAN).

## What got removed

* MAVLink 1 is no longer the default protocol version. MAVLink 2 is now used by default on all channels. MAVLink 1 is still available as opt-in.
* Remove the 1% deadzone and `RC{1..18}_DZ` parameters for RC channels 1-8.
* Remove CM8JL65 and TeraRanger distance sensor drivers from common builds to save flash. These sensors are end-of-life.

## Parameter Changelog

### Removed Parameters

| Parameter                                                                   | Group                        | Reason                                                               |
| --------------------------------------------------------------------------- | ---------------------------- | -------------------------------------------------------------------- |
| `BAT{1..2}_I_CHANNEL`, `BAT_ADC_CHANNEL`                                    | Battery Calibration          | Removed due to being unused                                          |
| `COM_FLT_PROFILE`                                                           | Commander                    | Removed due to being unused                                          |
| `COM_HLDL_REG_T`                                                            | Commander                    | Removed due to being unused                                          |
| `COM_KILL_DISARM`                                                           | Commander                    | Removed, now hardcoded to previous default of 5s                     |
| `COM_MOT_TEST_EN`                                                           | Commander                    | Removed due to being unused. Actuator testing now always enabled     |
| `COM_POSCTL_NAVL`                                                           | Commander                    | Not needed anymore as the Descend fallback provides nudging          |
| `COM_RC_ARM_HYST`                                                           | Commander                    | Removed, now hardcoded to previous default of 1s                     |
| `DSHOT_BIDIR_EN`                                                            | DShot                        | Replaced by `DSHOT_BIDIR_EDT`                                        |
| `EKF2_AGP_*`                                                                | EKF2                         | Replaced by `EKF2_AGP{0..3}_*`                                       |
| `EKF2_AGP_DELAY`                                                            | EKF2                         | Replaced by `EKF2_AGP{0..3}_DELAY`                                   |
| `EKF2_AGP_GATE`                                                             | EKF2                         | Replaced by `EKF2_AGP{0..3}_GATE`                                    |
| `EKF2_AGP_MODE`                                                             | EKF2                         | Replaced by `EKF2_AGP{0..3}_MODE`                                    |
| `EKF2_AGP_NOISE`                                                            | EKF2                         | Replaced by `EKF2_AGP{0..3}_NOISE`                                   |
| `EKF2_GPS_DELAY`                                                            | EKF2                         | Replaced by `SENS_GPS{0,1}_DELAY`                                    |
| `EKF2_GPS_POS_X`                                                            | EKF2                         | Replaced by `SENS_GPS{0,1}_OFFX`                                     |
| `EKF2_GPS_POS_Y`                                                            | EKF2                         | Replaced by `SENS_GPS{0,1}_OFFY`                                     |
| `EKF2_GPS_POS_Z`                                                            | EKF2                         | Replaced by `SENS_GPS{0,1}_OFFZ`                                     |
| `FD_ACT_MOT_C2T`                                                            | Failure Detector             | Renamed to `MOTFAIL_C2T`                                             |
| `FD_ACT_MOT_THR`                                                            | Failure Detector             | Renamed to `MOTFAIL_THR`                                             |
| `FD_ACT_MOT_TOUT`                                                           | Failure Detector             | Renamed to `MOTFAIL_TIME`                                            |
| `FD_ESCS_EN`                                                                | Failure Detector             | Included in `COM_ARM_CHK_ESCS`                                       |
| `FW_AT_START`, `MC_AT_START`                                                | Autotune                     | Autotune now started with `MAV_CMD_DO_AUTOTUNE_ENABLE` or AUX switch |
| `LNDMC_TRIG_TIME`                                                           | Land Detector                | Removed due to being unused                                          |
| `MOT_POLE_COUNT`                                                            | DShot                        | Replaced by per-channel `DSHOT_MOT_POL{1..12}`                       |
| `MPC_USE_HTE`                                                               | Multicopter Position Control | Removed, hover thrust estimator always enabled                       |
| `PD_GRIPPER_EN`                                                             | Payload Deliverer            | Removed, Module now starts automatically if in build                 |
| `RC{1..18}_DZ`                                                              | RC                           | Removed due to being unused                                          |
| `SENS_IMU_TEMP`                                                             | Sensors                      | Replaced by `HEATER{1..3}_TEMP`                                      |
| `SENS_IMU_TEMP_FF`                                                          | Sensors                      | Replaced by `HEATER{1..3}_TEMP_FF`                                   |
| `SENS_IMU_TEMP_I`                                                           | Sensors                      | Replaced by `HEATER{1..3}_TEMP_I`                                    |
| `SENS_IMU_TEMP_P`                                                           | Sensors                      | Replaced by `HEATER{1..3}_TEMP_P`                                    |
| `SENS_TEMP_ID`                                                              | Sensors                      | Replaced by `HEATER{1..3}_IMU_ID`                                    |
| `UAVCAN_LGT_ANTCL`, `UAVCAN_LGT_LAND`, `UAVCAN_LGT_NAV`, `UAVCAN_LGT_STROB` | UAVCAN                       | Now included in `UAVCAN_LGT_MODE`                                    |

### New Parameters

| Parameter                                                                                                 | Group               | Description                                                                     |
| --------------------------------------------------------------------------------------------------------- | ------------------- | ------------------------------------------------------------------------------- |
| [`ADC_ADS7953_EN`](https://docs.px4.io/main/en/advanced_config/parameter_reference#ADC_ADS7953_EN)        | ADC                 | Enable ADS7953                                                                  |
| [`ADC_ADS7953_REFV`](https://docs.px4.io/main/en/advanced_config/parameter_reference#ADC_ADS7953_REFV)    | ADC                 | Applied reference Voltage                                                       |
| [`ADC_TLA2528_EN`](https://docs.px4.io/main/en/advanced_config/parameter_reference#ADC_TLA2528_EN)        | ADC                 | Enable TLA2528                                                                  |
| [`ADC_TLA2528_REFV`](https://docs.px4.io/main/en/advanced_config/parameter_reference#ADC_TLA2528_REFV)    | ADC                 | Applied reference Voltage                                                       |
| [`BAT{1,2}_I_FILT`](https://docs.px4.io/main/en/advanced_config/parameter_reference#BAT1_I_FILT)          | Battery Calibration | Battery {1,2} current filter time constant                                      |
| [`BAT{1,2}_V_FILT`](https://docs.px4.io/main/en/advanced_config/parameter_reference#BAT1_V_FILT)          | Battery Calibration | Battery {1,2} voltage filter time constant                                      |
| [`CANNODE_NODE_ID`](https://docs.px4.io/main/en/advanced_config/parameter_reference#CANNODE_NODE_ID)      | UAVCAN              | UAVCAN CAN node ID (0 for dynamic allocation)                                   |
| [`CANNODE_PUB_BAR`](https://docs.px4.io/main/en/advanced_config/parameter_reference#CANNODE_PUB_BAR)      | UAVCAN              | Enable barometer publication                                                    |
| [`CANNODE_PUB_MAG`](https://docs.px4.io/main/en/advanced_config/parameter_reference#CANNODE_PUB_MAG)      | UAVCAN              | Enable magnetometer publication                                                 |
| [`CA_ICE_PERIOD`](https://docs.px4.io/main/en/advanced_config/parameter_reference#CA_ICE_PERIOD)          | Geometry            | Ice shedding cycle period                                                       |
| [`CA_SV_FLAP_SLEW`](https://docs.px4.io/main/en/advanced_config/parameter_reference#CA_SV_FLAP_SLEW)      | Geometry            | Control Surface slew rate for normalized flaps setpoint                         |
| `CA_TKO_PS{0..3}_CH`                                                                                      | Geometry            | Surface lock during fixed-wing takeoff: servo {1..3} channel                    |
| `CA_TKO_PS{1..3}_DY`                                                                                      | Geometry            | Surface lock during fixed-wing takeoff: servo {1..3} unlock delay after takeoff |
| [`COM_ARM_ON_BOOT`](https://docs.px4.io/main/en/advanced_config/parameter_reference#COM_ARM_ON_BOOT)      | Commander           | Arm automatically on boot                                                       |
| [`COM_ARM_TRAFF`](https://docs.px4.io/main/en/advanced_config/parameter_reference#COM_ARM_TRAFF)          | Commander           | Enable Traffic Avoidance system detection check                                 |
| [`DSHOT_BIDIR_EDT`](https://docs.px4.io/main/en/advanced_config/parameter_reference#DSHOT_BIDIR_EDT)      | DShot               | Enable Extended DShot Telemetry                                                 |
| [`DSHOT_ESC_TYPE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#DSHOT_ESC_TYPE)        | DShot               | ESC Type                                                                        |
| [`DSHOT_MOT_POL{1..12}`](https://docs.px4.io/main/en/advanced_config/parameter_reference#DSHOT_MOT_POL1)  | DShot               | Number of magnetic poles of motor {1..12}                                       |
| [`EKF2_AGP{0..3}_CTRL`](https://docs.px4.io/main/en/advanced_config/parameter_reference#EKF2_AGP0_CTRL)   | EKF2                | Auxiliary global position sensor aiding                                         |
| [`EKF2_AGP{0..3}_DELAY`](https://docs.px4.io/main/en/advanced_config/parameter_reference#EKF2_AGP0_DELAY) | EKF2                | Auxiliary global position sensor delay (to IMU)                                 |
| [`EKF2_AGP{0..3}_GATE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#EKF2_AGP0_GATE)   | EKF2                | Gate size for auxiliary global position sensor fusion                           |
| [`EKF2_AGP{0..3}_ID`](https://docs.px4.io/main/en/advanced_config/parameter_reference#EKF2_AGP0_ID)       | EKF2                | Auxiliary global position sensor ID                                             |
| [`EKF2_AGP{0..3}_MODE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#EKF2_AGP0_MODE)   | EKF2                | Fusion reset mode for sensor                                                    |
| [`EKF2_AGP{0..3}_NOISE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#EKF2_AGP0_NOISE) | EKF2                | Measurement noise for auxiliary global position sensor                          |
| [`EKF2_REQ_FIX`](https://docs.px4.io/main/en/advanced_config/parameter_reference#EKF2_REQ_FIX)            | EKF2                | Minimum GNSS Fix type required for GNSS usage                                   |
| `EKF2_RNGBC_CTRL`                                                                                         | EKF2                | Ranging beacon fusion control                                                   |
| `EKF2_RNGBC_DELAY`                                                                                        | EKF2                | Ranging beacon measurement delay relative to IMU measurements                   |
| `EKF2_RNGBC_GATE`                                                                                         | EKF2                | Gate size for ranging beacon fusion                                             |
| `EKF2_RNGBC_NOISE`                                                                                        | EKF2                | Measurement noise for ranging beacon fusion                                     |
| `EKF2_SENS_EN`                                                                                            | EKF2                | Sensor fusion enable bitmask                                                    |
| [`GPS_UBX_DGNSS_TO`](https://docs.px4.io/main/en/advanced_config/parameter_reference#GPS_UBX_DGNSS_TO)    | GNSS                | u-blox GNSS DGNSS timeout                                                       |
| [`GPS_UBX_JAM_DET`](https://docs.px4.io/main/en/advanced_config/parameter_reference#GPS_UBX_JAM_DET)      | GNSS                | u-blox GNSS jamming detection high sensitivity mode                             |
| [`GPS_UBX_MIN_CNO`](https://docs.px4.io/main/en/advanced_config/parameter_reference#GPS_UBX_MIN_CNO)      | GNSS                | u-blox GNSS minimum satellite signal level for navigation                       |
| [`GPS_UBX_MIN_ELEV`](https://docs.px4.io/main/en/advanced_config/parameter_reference#GPS_UBX_MIN_ELEV)    | GNSS                | u-blox GNSS minimum elevation for a GNSS satellite to be used in navigation     |
| [`GPS_UBX_PPK`](https://docs.px4.io/main/en/advanced_config/parameter_reference#GPS_UBX_PPK)              | GNSS                | Enable MSM7 message output for PPK workflow                                     |
| [`GPS_UBX_RATE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#GPS_UBX_RATE)            | GNSS                | u-blox GNSS output rate                                                         |
| [`GRF_RATE_CFG`](https://docs.px4.io/main/en/advanced_config/parameter_reference#GRF_RATE_CFG)            | Sensors             | Lightware GRF lidar update rate                                                 |
| [`GRF_SENS_MODEL`](https://docs.px4.io/main/en/advanced_config/parameter_reference#GRF_SENS_MODEL)        | Sensors             | GRF Sensor model                                                                |
| [`HEATER{1..3}_IMU_ID`](https://docs.px4.io/main/en/advanced_config/parameter_reference#HEATER1_IMU_ID)   | Sensors             | The ID of the IMU controlled by heater {1..3}                                   |
| [`HEATER{1..3}_TEMP`](https://docs.px4.io/main/en/advanced_config/parameter_reference#HEATER1_TEMP)       | Sensors             | Target temperature for heater {1..3}                                            |
| [`HEATER{1..3}_TEMP_FF`](https://docs.px4.io/main/en/advanced_config/parameter_reference#HEATER1_TEMP_FF) | Sensors             | IMU heater controller {1..3} feedforward value                                  |
| [`HEATER{1..3}_TEMP_I`](https://docs.px4.io/main/en/advanced_config/parameter_reference#HEATER1_TEMP_I)   | Sensors             | IMU heater controller {1..3} integrator gain value                              |
| [`HEATER{1..3}_TEMP_P`](https://docs.px4.io/main/en/advanced_config/parameter_reference#HEATER1_TEMP_P)   | Sensors             | IMU heater controller {1..3} proportional gain value                            |
| [`ILABS_MODE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#ILABS_MODE)                | Sensors             | InertialLabs INS sensor mode configuration                                      |
| [`MOTFAIL_C2T`](https://docs.px4.io/main/en/advanced_config/parameter_reference#MOTFAIL_C2T)              | Motor Failure       | Motor Failure Current/Throttle Scale                                            |
| [`MOTFAIL_HIGH_OFF`](https://docs.px4.io/main/en/advanced_config/parameter_reference#MOTFAIL_HIGH_OFF)    | Motor Failure       | Overcurrent motor failure limit offset                                          |
| [`MOTFAIL_LOW_OFF`](https://docs.px4.io/main/en/advanced_config/parameter_reference#MOTFAIL_LOW_OFF)      | Motor Failure       | Undercurrent motor failure limit offset                                         |
| [`MOTFAIL_TIME`](https://docs.px4.io/main/en/advanced_config/parameter_reference#MOTFAIL_TIME)            | Motor Failure       | Motor Failure Hysteresis Time                                                   |
| [`NAV_LTR_LAST_DL`](https://docs.px4.io/main/en/advanced_config/parameter_reference#NAV_LTR_LAST_DL)      | Mission             | Loiter at last GCS heartbeat position on data link loss                         |
| [`PCA9685_I2C_ADDR`](https://docs.px4.io/main/en/advanced_config/parameter_reference#PCA9685_I2C_ADDR)    | Actuator Outputs    | I2C address of PCA9685                                                          |
| [`PPS_CAP_GPS_ID`](https://docs.px4.io/main/en/advanced_config/parameter_reference#PPS_CAP_GPS_ID)        | GNSS                | PPS capture GNSS receiver device ID                                             |
| [`SBG_BAUDRATE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SBG_BAUDRATE)            | Sensors             | sbgECom driver baudrate                                                         |
| [`SBG_CONFIGURE_EN`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SBG_CONFIGURE_EN)    | Sensors             | sbgECom driver INS configuration enable                                         |
| [`SBG_MODE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SBG_MODE)                    | Sensors             | sbgECom driver mode                                                             |
| [`SENS_BAHRS_CFG`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SENS_BAHRS_CFG)        | Sensors             | Serial Configuration for EULER-NAV BAHRS                                        |
| [`SENS_EN_GRF_CFG`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SENS_EN_GRF_CFG)      | Sensors             | Serial Configuration for Lightware GRF Rangefinder (serial)                     |
| [`SENS_EN_MCP9808`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SENS_EN_MCP9808)      | Sensors             | Enable MCP9808 temperature sensor (external I2C)                                |
| [`SENS_EN_TMP102`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SENS_EN_TMP102)        | Sensors             | Enable TMP102                                                                   |
| [`SENS_GPS{0,1}_DELAY`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SENS_GPS0_DELAY)  | Sensors             | GNSS measurement delay                                                          |
| [`SENS_GPS{0,1}_ID`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SENS_GPS0_ID)        | Sensors             | GNSS device ID                                                                  |
| [`SENS_GPS{0,1}_OFFX`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SENS_GPS0_OFFX)    | Sensors             | GNSS antenna X position                                                         |
| [`SENS_GPS{0,1}_OFFY`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SENS_GPS0_OFFY)    | Sensors             | GNSS antenna Y position                                                         |
| [`SENS_GPS{0,1}_OFFZ`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SENS_GPS0_OFFZ)    | Sensors             | GNSS antenna Z position                                                         |
| [`SENS_ILABS_CFG`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SENS_ILABS_CFG)        | Sensors             | Serial Configuration for InertialLabs                                           |
| [`SENS_SBG_CFG`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SENS_SBG_CFG)            | Sensors             | Serial Configuration for sbgECom                                                |
| [`SF1XX_ROT`](https://docs.px4.io/main/en/advanced_config/parameter_reference#SF1XX_ROT)                  | Sensors             | Lightware laser rangefinder Rotation                                            |
| [`UAVCAN_LGT_FN{0..15}`](https://docs.px4.io/main/en/advanced_config/parameter_reference#UAVCAN_LGT_FN0)  | UAVCAN              | UAVCAN Light function                                                           |
| [`UAVCAN_LGT_ID{0..15}`](https://docs.px4.io/main/en/advanced_config/parameter_reference#UAVCAN_LGT_FN0)  | UAVCAN              | UAVCAN Light ID                                                                 |
| [`UAVCAN_LGT_MODE`](https://docs.px4.io/main/en/advanced_config/parameter_reference#UAVCAN_LGT_MODE)      | UAVCAN              | UAVCAN Navigation light operating mode                                          |
| [`UAVCAN_LGT_NUM`](https://docs.px4.io/main/en/advanced_config/parameter_reference#UAVCAN_LGT_NUM)        | UAVCAN              | Number of UAVCAN lights to configure                                            |
| [`UAVCAN_SUB_MBD`](https://docs.px4.io/main/en/advanced_config/parameter_reference#UAVCAN_SUB_MBD)        | UAVCAN              | subscription MovingBaselineData                                                 |
| [`UXRCE_DDS_FLCTRL`](https://docs.px4.io/main/en/advanced_config/parameter_reference#UXRCE_DDS_FLCTRL)    | UXRCE-DDS Client    | Enable serial flow control for UXRCE interface                                  |
| [`UXRCE_DDS_NS_IDX`](https://docs.px4.io/main/en/advanced_config/parameter_reference#UXRCE_DDS_NS_IDX)    | UXRCE-DDS Client    | Define an index-based message namespace                                         |
| [`VOXL_ESC_CMD`](https://docs.px4.io/main/en/advanced_config/parameter_reference#VOXL_ESC_CMD)            | VOXL ESC            | UART ESC command type                                                           |
| [`VOXL_ESC_PWR_MIN`](https://docs.px4.io/main/en/advanced_config/parameter_reference#VOXL_ESC_PWR_MIN)    | VOXL ESC            | UART ESC Minimum motor power                                                    |
| [`VOXL_ESC_T_ON`](https://docs.px4.io/main/en/advanced_config/parameter_reference#VOXL_ESC_T_ON)          | VOXL ESC            | UART ESC Turtle Mode button index for MAVLink manual control                    |

### Changed Default values

| Parameter          | Group                        | Old    | New  |
| ------------------ | ---------------------------- | ------ | ---- |
| `EKF2_MIN_RNG`     | EKF2                         | 0.1    | 0.01 |
| `FD_ACT_EN`        | Motor Failure                | 1      | 0    |
| `FW_GC_EN`         | FW Rate Control              | 0      | 1    |
| `MAV_PROTO_VER`    | MAVLink                      | 0      | 2    |
| `MPC_LAND_RADIUS`  | Multicopter Position Control | 1000.0 | -1.0 |
| `PD_GRIPPER_TO`    | Payload Deliverer            | 3.0    | 1.0  |
| `RBCLW_DIS1`       | Actuator Outputs             | 128    | 127  |
| `RBCLW_DIS2`       | Actuator Outputs             | 128    | 127  |
| `RBCLW_MAX1`       | Actuator Outputs             | 256    | 254  |
| `RBCLW_MAX2`       | Actuator Outputs             | 256    | 254  |
| `RBCLW_MIN1`       | Actuator Outputs             | 1      | 0    |
| `RBCLW_MIN2`       | Actuator Outputs             | 1      | 0    |
| `VT_LND_PITCH_MIN` | VTOL Attitude Control        | -5.0   | 0.0  |
| `VT_PITCH_MIN`     | VTOL Attitude Control        | -5.0   | 0.0  |


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