What is terrain mesh in Prepar3D, and how do I install it?

Terrain mesh in Prepar3D is elevation data that defines the three-dimensional shape of the ground—mountains, valleys, cliffs and slopes. It does not supply aerial imagery, landclass, buildings or airports. Install it as a scenery package, activate it through its add-on.xml file or the Scenery Library, then match Prepar3D’s mesh settings to the source resolution.

What does terrain mesh change in Prepar3D?

Terrain mesh changes ground elevation and shape by supplying a grid of height points, usually stored in one or more .bgl files. Prepar3D draws the terrain between those points and places textures, roads, water and scenery objects over the resulting surface.

A resolution quoted in metres normally describes the approximate horizontal spacing between elevation samples, not texture sharpness or guaranteed vertical accuracy. An LOD number is another way of describing mesh density, but it should not be treated as the same number of metres. Use the package documentation when choosing settings.

If the distinction is unclear, our explanation of how terrain elevation differs from textures and scenery objects covers each layer separately. Installing mesh will not sharpen blurred ground imagery or add missing landmarks.

How do I install terrain mesh in Prepar3D?

First identify how the package is meant to be registered. Prepar3D supports traditional Scenery Library folders and newer add-on packages; registering the same mesh through both methods creates an unnecessary duplicate layer.

1. Check compatibility. Confirm that the mesh supports your Prepar3D generation. A BGL may work across several versions while its installer or configuration method does not.
2. Close Prepar3D and extract the archive fully. Do not run the scenery directly from a ZIP file, and avoid installing into Prepar3D’s core folders unless the package explicitly requires it.
3. Inspect the folder structure. A typical legacy layout is MeshName\Scenery\*.bgl. The mistake we see most often is an extra nested folder such as MeshName\MeshName\Scenery.
4. Register the package once. For legacy scenery, open the Scenery Library, add an area and select MeshName—the folder directly containing Scenery. For an add-on.xml package, retain its complete structure and use the location specified by its instructions. A version-specific Prepar3D Add-ons folder under Documents is common, but it is not mandatory for every package.
5. Place it at a sensible priority. Put broad global mesh below regional scenery, local airport packages and their elevation corrections unless the mesh documentation says otherwise.
6. Adjust the display settings. Set Mesh Resolution equal to or finer than the source data and raise Mesh Complexity enough to retain the terrain shape.
7. Restart and verify it. Load a location inside the mesh coverage, use a repeatable camera position and compare the result with the layer enabled and disabled.

Prepar3D v5 users can follow our version-specific scenery registration procedure if the menus or package discovery differ from older instructions. Our worked global-mesh installation example also shows a practical legacy folder layout and ordering method.

Where should terrain mesh sit in the Scenery Library?

Global terrain mesh should normally sit low in the library, with regional scenery and airports above it. This keeps the library organised and allows local flattens, exclusions and elevation corrections to retain their intended priority.

Mesh selection is not controlled by library order alone. Prepar3D generally favours the highest-resolution elevation data covering a location, even when that layer is lower in the library. Priority becomes more relevant where overlapping meshes have the same effective resolution or where another scenery layer supplies terrain corrections.

• Keep one broad global mesh below more specialised regional packages.
• Keep airport scenery and its documented elevation files above broad mesh.
• Do not move mesh above orthophoto imagery expecting sharper textures; imagery is draped over the elevation surface.
• Do not activate identical BGLs through both the Scenery Library and an add-on.xml package.

Which Prepar3D mesh settings should I use?

Mesh Resolution limits the finest elevation data Prepar3D may display, while Mesh Complexity controls how fully that shape is represented. Start with the package author’s recommendations, then reduce the settings only if loading or performance suffers.

• Mesh Resolution: choose a value equal to or finer than the installed source. A finer setting cannot create detail absent from the data.
• Mesh Complexity: raise it progressively if ridges and valleys look simplified. Maximum complexity is not automatically necessary for every mesh.
• Texture Resolution: this affects ground imagery, not elevation detail, so it will not fix flat mountains.

Very dense mesh can increase terrain loading and cause stutters on constrained systems. Lower Mesh Resolution or Mesh Complexity before removing the package, then compare the same flight and viewpoint.

Why is my Prepar3D terrain mesh not working?

Most mesh failures come from incorrect registration, an unsuitable display setting or another elevation source taking precedence.

• The layer is listed but nothing changes: confirm that your aircraft is inside the mesh coverage. Prepar3D’s default or another add-on mesh may already provide equal or finer data there.
• The package is not detected: check for an extra nested folder, a misplaced add-on.xml or a legacy entry pointing at Scenery instead of its parent folder.
• Airports sit on plateaux or in trenches: the airport reference elevation or flatten does not match the mesh. Keep the airport package above broad mesh and install its documented compatibility patch. Disable an old elevation-correction BGL only when the airport documentation identifies it; never delete a default Prepar3D file as a guess.
• Mountains have spikes or deep tears: disable overlapping terrain packages one at a time. Corrupt extraction, incompatible BGLs and competing high-resolution meshes are common causes.
• Coastlines or water look wrong: mesh controls elevation, but shoreline and water boundaries may come from separate vector scenery. Reordering mesh alone may not resolve that mismatch.
• The ground is blurry: this is a texture, landclass or orthophoto issue rather than a terrain-mesh fault.

How do I remove terrain mesh safely?

Disable the mesh before deleting its files. Remove a legacy entry from the Scenery Library, or disable an add-on package through Prepar3D’s add-on management, then close the simulator and delete the package folder. Use its uninstaller when one was supplied, and never remove or overwrite stock terrain BGLs.