# PX4 SITL “Takeoff detected” but drone stays on ground (Gazebo + MAVSDK) **URL:** \ **Category:** PX4 Autopilot\ **Created:** [December 15, 2025, 12:27pm UTC](https://discuss.px4.io/t/px4-sitl-takeoff-detected-but-drone-stays-on-ground-gazebo-mavsdk/48126 "2025-12-15T12:27:24Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Udbhaw\_Anand](https://discuss.px4.io/user_avatar/discuss.px4.io/udbhaw_anand/32/20837_2.png) [@Udbhaw\_Anand](https://discuss.px4.io/u/Udbhaw_Anand)\ **Post date:** [December 15, 2025, 12:27pm UTC](https://discuss.px4.io/t/px4-sitl-takeoff-detected-but-drone-stays-on-ground-gazebo-mavsdk/48126/1 "2025-12-15T12:27:24Z")
PX4 **accepts the takeoff command** (vehicle arms and reports “takeoff detected”), but in Gazebo the drone **does not receive effective upward thrust** , so it stays on the ground. In this state, PX4 logically transitions to takeoff, but **the motors never execute a real climb command** in the simulator. Terminal Commands udbhaw@udbhaw-LOQ-15IRX9:~$ cd ~/PX4-Autopilot udbhaw@udbhaw-LOQ-15IRX9:~/PX4-Autopilot$ make px4\_sitl gazebo-classic [0/4] Performing build step for ‘sitl\_gazebo-classic’ ninja: no work to do. [3/4] cd /home/udbhaw/PX4-Autopilot/bu…w/PX4-Autopilot/build/px4\_sitl\_default SITL ARGS sitl\_bin: /home/udbhaw/PX4-Autopilot/build/px4\_sitl\_default/bin/px4 debugger: none model: iris world: none src\_path: /home/udbhaw/PX4-Autopilot build\_path: /home/udbhaw/PX4-Autopilot/build/px4\_sitl\_default GAZEBO\_PLUGIN\_PATH /usr/lib/x86\_64-linux-gnu/gazebo-11/plugins::/home/udbhaw/PX4-Autopilot/build/px4\_sitl\_default/build\_gazebo-classic GAZEBO\_MODEL\_PATH /home/udbhaw/ardupilot\_gazebo/models:/home/udbhaw/PX4-Autopilot/Tools/simulation/gazebo-classic/sitl\_gazebo-classic/models LD\_LIBRARY\_PATH /opt/ros/humble/opt/rviz\_ogre\_vendor/lib:/opt/ros/humble/lib/x86\_64-linux-gnu:/opt/ros/humble/lib::/usr/lib/x86\_64-linux-gnu/gazebo-11/plugins::/home/udbhaw/PX4-Autopilot/build/px4\_sitl\_default/build\_gazebo-classic empty world, setting empty.world as default Using: /home/udbhaw/PX4-Autopilot/Tools/simulation/gazebo-classic/sitl\_gazebo-classic/models/iris/iris.sdf (gzserver:11795): GStreamer-App-CRITICAL \*\*: 17:52:29.839: gst\_app\_src\_push\_internal: assertion ‘GST\_IS\_APP\_SRC (appsrc)’ failed (gzserver:11795): GLib-CRITICAL \*\*: 17:52:29.840: g\_main\_loop\_quit: assertion ‘loop != NULL’ failed (gzserver:11795): GStreamer-App-CRITICAL \*\*: 17:52:29.865: gst\_app\_src\_push\_internal: assertion ‘GST\_IS\_APP\_SRC (appsrc)’ failed (gzserver:11795): GStreamer-App-CRITICAL \*\*: 17:52:29.869: gst\_app\_src\_push\_internal: assertion ‘GST\_IS\_APP\_SRC (appsrc)’ failed SITL COMMAND: “/home/udbhaw/PX4-Autopilot/build/px4\_sitl\_default/bin/px4” “/home/udbhaw/PX4-Autopilot/build/px4\_sitl\_default”/etc * * * | \__\_ \ \ \ / / / | | |/ / \ V / / /| | | \_\_/ / \ / /_| | | | / /^\ \ \_\_ | \_| / / |\_/ px4 starting. INFO [px4] startup script: /bin/sh etc/init.d-posix/rcS 0 INFO [init] found model autostart file as SYS\_AUTOSTART=10015 INFO [param] selected parameter default file parameters.bson INFO [param] importing from ‘parameters.bson’ INFO [parameters] BSON document size 316 bytes, decoded 316 bytes (INT32:13, FLOAT:3) INFO [param] selected parameter backup file parameters\_backup.bson INFO [dataman] data manager file ‘./dataman’ size is 7866640 bytes etc/init.d-posix/rcS: 39: [: Illegal number: INFO [init] PX4\_SIM\_HOSTNAME: localhost INFO [simulator\_mavlink] Waiting for simulator to accept connection on TCP port 4560 INFO [simulator\_mavlink] Simulator connected on TCP port 4560. INFO [lockstep\_scheduler] setting initial absolute time to 2760000 us INFO [commander] LED: open /dev/led0 failed (22) WARN [health\_and\_arming\_checks] Preflight Fail: ekf2 missing data INFO [mavlink] mode: Normal, data rate: 4000000 B/s on udp port 18570 remote port 14550 Gazebo multi-robot simulator, version 11.10.2 Copyright (C) 2012 Open Source Robotics Foundation. Released under the Apache 2 License. > **[Gazebo](https://gazebosim.org/)** > > Simulation Driven Robotics. Iterate quickly on design concepts and control strategies with Gazebo's rich suite of tools, libraries, and cloud services. [Msg] Waiting for master. [Msg] Connected to gazebo master @ [http://127.0.0.1:11345](http://127.0.0.1:11345) [Msg] Publicized address: 192.168.1.48 INFO [mavlink] mode: Onboard, data rate: 4000000 B/s on udp port 14580 remote port 14540 INFO [mavlink] mode: Onboard, data rate: 4000 B/s on udp port 14280 remote port 14030 INFO [mavlink] mode: Gimbal, data rate: 400000 B/s on udp port 13030 remote port 13280 INFO [logger] logger started (mode=all) INFO [logger] Start file log (type: full) INFO [logger] [logger] ./log/2025-12-15/12\_22\_32.ulg INFO [logger] Opened full log file: ./log/2025-12-15/12\_22\_32.ulg INFO [mavlink] MAVLink only on localhost (set param MAV\_{i}_BROADCAST = 1 to enable network) INFO [mavlink] MAVLink only on localhost (set param MAV_{i}\_BROADCAST = 1 to enable network) INFO [px4] Startup script returned successfully pxh\> INFO [tone\_alarm] home set [Wrn] [ModelDatabase.cc:212] Unable to connect to model database using [//database.config]. Only locally installed models will be available. INFO [tone\_alarm] notify negative [Wrn] [Event.cc:61] Warning: Deleting a connection right after creation. Make sure to save the ConnectionPtr from a Connect call INFO [commander] Ready for takeoff! pxh\> commander takeoff pxh\> INFO [commander] Armed by internal command INFO [tone\_alarm] arming warning INFO [navigator] Using minimum takeoff altitude: 2.50 m INFO [commander] Takeoff detected ---
**Author:** ![JulianOes](https://discuss.px4.io/user_avatar/discuss.px4.io/julianoes/32/30_2.png) [@JulianOes](https://discuss.px4.io/u/JulianOes)\ **Post date:** [December 15, 2025, 11:03pm UTC](https://discuss.px4.io/t/px4-sitl-takeoff-detected-but-drone-stays-on-ground-gazebo-mavsdk/48126/2 "2025-12-15T23:03:52Z")
Are the motors configured in the actuators tab in QGC? Which PX4 version are you using? ---
**Author:** ![system](https://discuss.px4.io/uploads/default/original/3X/7/3/73ce918bdcd64854de904f0c8d9ab70ca9723f2a.png) [@system](https://discuss.px4.io/u/system)\ **Post date:** [March 15, 2026, 11:04pm UTC](https://discuss.px4.io/t/px4-sitl-takeoff-detected-but-drone-stays-on-ground-gazebo-mavsdk/48126/3 "2026-03-15T23:04:53Z")
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