> For the complete documentation index, see [llms.txt](https://docs.bestway.com.ua/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.bestway.com.ua/modeling/vehicle-model-setup-pipeline/bone-hierarchy-in-vehicle-models/engine.md).

# Engine

The `engine` bone corresponds to the **Engine** component. It can be either invisible or contain a visible mesh.\
It has a volume, `engine_vol`, which is hidden inside the volumes of the `body_vol` group.

**Properties of the `engine` bone**

<table data-header-hidden><thead><tr><th width="167">Property</th><th>Description</th></tr></thead><tbody><tr><td><code>poly</code></td><td>Makes the component visible.</td></tr><tr><td><code>id=engine</code></td><td>Identifier of the <strong>Engine</strong> component.</td></tr><tr><td><code>Animation</code></td><td>Specifies the animation name (if available).</td></tr></tbody></table>

#### **Checklist of possible elements linked to the `engine` bone**

<figure><img src="https://2358506489-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2UV9d5d9aTZPISbocWyo%2Fuploads%2F1OXgOJPg3ZDu1GucB9tV%2Fimage.png?alt=media&amp;token=bb98c84d-6ccb-4036-9ba9-4c4902445b65" alt=""><figcaption><p>Elements linked to the engine bone</p></figcaption></figure>

Depending on the model, the following elements may be linked to the `engine` bone

* Engine\_LOD branches
* **Secondary bones**
  * `cover`: hatch bones, if specified by the model's design
  * `detail`: additional details, if specified by the model's design
* **Helper bones**:
  * `FXsmoke`: exhaust smoke effec
  * `FXfire`: engine fire effect
  * `fxstop1`: brake lights
  * `seat`: bones for passengers