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# LaunchDetectionStatus (UORB message)

Status of the launch detection state machine (fixed-wing only).

**TOPICS:** launch_detection_status

## Fields

| Name                              | Type     | Unit [Frame] | Range/Enum | Description                                                                                                   |
| --------------------------------- | -------- | ------------ | ---------- | ------------------------------------------------------------------------------------------------------------- |
| timestamp                         | `uint64` |              |            | time since system start (microseconds)                                                                        |
| launch_detection_state            | `uint8`  |              |            |
| selected_control_surface_disarmed | `bool`   |              |            | flag indicating whether selected actuators should kept disarmed (have to be configured in control allocation) |

## Constants

| Name                                                                                    | Type    | Value | Description                                                                                       |
| --------------------------------------------------------------------------------------- | ------- | ----- | ------------------------------------------------------------------------------------------------- |
| <a id="#STATE_WAITING_FOR_LAUNCH"></a> STATE_WAITING_FOR_LAUNCH                         | `uint8` | 0     | waiting for launch                                                                                |
| <a id="#STATE_LAUNCH_DETECTED_DISABLED_MOTOR"></a> STATE_LAUNCH_DETECTED_DISABLED_MOTOR | `uint8` | 1     | launch detected, but keep motor(s) disabled (e.g. because it can't spin freely while on catapult) |
| <a id="#STATE_FLYING"></a> STATE_FLYING                                                 | `uint8` | 2     | launch detected, use normal takeoff/flying configuration                                          |

## Source Message

[Source file (GitHub)](https://github.com/PX4/PX4-Autopilot/blob/main/msg/LaunchDetectionStatus.msg)

::: details Click here to see original file

```c
# Status of the launch detection state machine (fixed-wing only)

uint64 timestamp # time since system start (microseconds)

uint8 STATE_WAITING_FOR_LAUNCH 			= 0 # waiting for launch
uint8 STATE_LAUNCH_DETECTED_DISABLED_MOTOR 	= 1 # launch detected, but keep motor(s) disabled (e.g. because it can't spin freely while on catapult)
uint8 STATE_FLYING 				= 2 # launch detected, use normal takeoff/flying configuration

uint8 launch_detection_state

bool selected_control_surface_disarmed		# [-] flag indicating whether selected actuators should kept disarmed (have to be configured in control allocation)
```

:::