# Data Link Loss Failsafe Trigger

<figure><img src="/files/6Nnv6kjfhENvHUg1jd77" alt=""><figcaption></figcaption></figure>

The **Data Link Loss Failsafe Trigger** controls the behavior of the vehicle when the telemetry link is lost.&#x20;

**Default Failsafe Action:** Return mode

**Default Data Link Loss Timeout:** 60s

Failsafe detection can trigger one of the following actions.

<table><thead><tr><th width="170"></th><th></th></tr></thead><tbody><tr><td><strong>Disabled</strong></td><td>No action (the failsafe will be ignored).</td></tr><tr><td><strong>Hold mode*</strong></td><td>The vehicle will enter Hold mode and orbit at the location where the failsafe action was triggered.</td></tr><tr><td><strong>Return mode</strong></td><td>The vehicle will enter Return mode and fly directly to the designated landing location at the set return altitude, then land.</td></tr><tr><td><strong>Land mode*</strong></td><td>The vehicle will enter Land mode and land immediately.</td></tr><tr><td><strong>Terminate*</strong></td><td>Turns off all controllers and sets all PWM outputs to their failsafe values. The failsafe outputs can be used to deploy a parachute, landing gear, or perform another operation.</td></tr><tr><td><strong>Lockdown*</strong></td><td>Kills the motors (sets them to disarmed).</td></tr></tbody></table>

(**\***&#x6F;nly available in AMC's Advanced Mode)

{% hint style="warning" %}
By default, when a loss of communication occurs, the DeltaQuad Evo Tactical will continue its **mission** if a mission plan is being executed.&#x20;

This behavior is inherent to the Evo Tactical, as a loss of communication is expected during missions with the stealth switch enabled.
{% endhint %}

{% hint style="warning" %}
The settings for the **Data Link Loss Failsafe Trigger** should be checked before pausing the vehicle mid-flight.

If the trigger is disabled and the data link is lost while the vehicle is paused and in **Hold** mode, the pilot will be unable to issue new commands. The DeltaQuad EVO will remain in **Hold** mode until the data link is re-established. If the data link cannot be restored, the vehicle will remain in **Hold** mode until the **Low Battery Failsafe Trigger** activates.
{% endhint %}

{% hint style="info" %}
Many local laws and regulations require the **Failsafe Action** to be set to **Return mode**.
{% endhint %}


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