Flight mode selector
Last updated
Last updated
Flight modes visualized in the flight mode selector provide the pilot different ways to fly manually.
Mission Control allows you to select one of the three safest and easiest flight modes. A new flight mode has been added which is the Position slow mode. This new mode can apply velocity constraints given by the system.
The mode selector displays the current flight mode, which changes automatically when an operation is performed (e.g. takeoff, land, start mission, etc.). Users can also select the mode selector to choose a manual flight mode: Altitude or Position mode.
This topic provides a high-level overview of the most important PX4 flight modes:
Mission Control supports three manual modes: Position mode and Altitude mode and Position Slow mode
Always prefer Position mode for manual flight (unless your vehicle does not have GPS)! Position mode is the easiest and safest manual flight mode, in particular for new fliers. It provides the most stable and predictable movement and is suitable for a wider range of applications and weather conditions.
The modes are enabled using the mode selector in the application status bar. PX4 will also switch to position mode (by default) if the sticks are moved when in an automatic mode.
These modes have (the same) intuitive flight controls, which make it simple to understand how the vehicle is expected to move. The controls make it impossible to flip or roll the vehicle, and easy to recover stability in the event of any problem.
The default multicopter stick controls are shown below.
When the sticks are centered, the flight modes have slightly different behavior:
Position mode uses the known position from GPS to maintain position (multicopter) or flight path (fixed-wing) against wind and other forces.
A multicopter will actively brake, level, and be locked to a position in 3D space — compensating for wind and other forces.
A fixed-wing will level out and hold its straight-line path (it will resist being moved off this track) — compensating for wind and other forces.
Altitude mode uses the known altitude from a barometer to maintain altitude but cannot maintain position: When you center the sticks:
A multicopter will maintain altitude, but will continue moving forward with existing momentum until slowed by air resistance, and may drift in response to wind and other forces.
A fixed-wing will level out but may change course in response to wind etc.
The modes are enabled using the mode selector in the application status bar. PX4 will also switch to position mode by default if the sticks are moved when in an automatic mode.
A multicopter in this mode will hover at its current position and altitude (maintaining position against wind and other forces) while a fixed-wing vehicle will hold altitude and circle the current position.
Hold mode is entered automatically after takeoff and landing modes complete, and when pausing a mission. It can also be activated with a pre-programmed RC switch.
This mode is started when you select Orbit at Location on the map.
The GoTo Task takes you to a specific location. This task is run from within Hold Mode when you select a Go to Location on the map.
(sub-topics for individual modes)
causes the vehicle to fly a clear path to a safe location. The mode can be activated manually by selecting the Return button () or using a predefined controller switch. It may also be entered automatically as a response to a vehicle failsafe being triggered (e.g. low battery).
The return behavior depends on vehicle settings, and may follow a mission path and/or mission landing pattern (if defined). By default a fixed wing vehicle will use a landing pattern defined in a mission while a multicopter will fly to the home location and land. For detailed configuration information see: .
initiates the automatic takeoff sequence. The mode can be activated by selecting the Takeoff button () when landed or using a pre-programmed RC switch.
On multicopter takeoff causes the vehicle to climb vertically until it reaches the takeoff altitude, and then switch to . On fixed wing, the launch behavior depends on the configured takeoff mode (catapult/hand-launch mode or runway takeoff mode).
initiates the automatic land sequence. The mode can be activated by selecting the Land button () when flying or using a pre-programmed RC switch.
On multicopter the vehicle will just descend and land. Fixed wing landing depends on vehicle configuration (for more information see: ).
is an automatic mode used to hold a vehicle at a particular location.
is used to execute a pre-planned mission. This mode is automatically activated when you start a mission.
starts a slow clockwise orbit at a specific location. The orbit altitude, speed, direction and radius can be modified using the UI or via an (optional) RC controller.
