AC3D to COLLADA Converter
FileFlip converts AC3D to COLLADA entirely inside your browser, using Assimp compiled to WebAssembly. The file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. That means no file-size limit, no queue and no account.
How do I convert an AC3D file to COLLADA?#
- Drop your AC3D file onto the converter at the top of this page, or click it to pick one from your computer. You can add as many as you like.
- Leave the target set to COLLADA and the conversion starts on its own. FileFlip downloads 11.2 MB of WebAssembly the first time and nothing after that, then runs Assimp on your own machine.
- Save the COLLADA file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting AC3D to COLLADA lose quality?#
Not in the sense of pixels or samples. Converting AC3D to COLLADA rebuilds the file in COLLADA's own model rather than re-encoding it, so everything COLLADA can represent comes through exactly and anything it cannot has to be dropped. Expect the geometry to be exact, and anything the target has no place for, such as a rig, to be left behind.
Is it safe to convert AC3D files online?#
Yes, because nothing is uploaded. FileFlip converts AC3D files inside the browser tab you already have open, using WebAssembly builds of the same engines a desktop converter would install. Your file is read from your own disk into the page's memory, and no request carrying it is ever made.
You do not have to take that on trust. Open your browser's network panel, run a conversion, and you will see the engine come down and your file go nowhere. There is no upload, no server-side copy, no retention window, and no account tied to what you converted.
How FileFlip works lists every engine, its version and its download size, and shows how to check for yourself that nothing leaves your machine.
What AC3D to COLLADA actually does to the file#
Converting AC3D to COLLADA runs on Assimp, downloads 11.2 MB of WebAssembly the first time and nothing after that, rebuilds the file in the target's own model.
| Engine | Assimp |
|---|---|
| Conversion path | One step: AC3D → COLLADA |
| Downloaded to your browser | 11.2 MB, once, then cached by your browser |
| Quality | Rebuilt in the target's model |
| You get back | One file |
| Where it runs | In a background worker, so the page stays responsive |
What survives the conversion
| What is in the file | This conversion | Why |
|---|---|---|
| Materials | Sometimes | Survives for some files and not others. |
| Textures | Sometimes | Survives for some files and not others. |
| Skeleton and animation | Sometimes | Survives for some files and not others. |
What is an AC3D file?#
An AC file is the plain-text scene format written by AC3D, a modeller aimed at flight-simulator and hobbyist work, storing a hierarchy of numbered OBJECT entries that each carry their own surfaces, materials and texture references.
Use AC when the destination is FlightGear or another AC3D-based scenery pipeline, since that's what the format was built to feed.
Convert AC to OBJ or glTF once a model needs to leave the flight-sim world, since few applications outside it open AC3D natively.
What is a COLLADA file?#
A DAE file is an XML document in the COLLADA schema, created at Sony Computer Entertainment in 2004 and now maintained by the Khronos Group, describing a 3D scene's geometry, materials, lights, cameras and animation so it can move between authoring tools that don't share a native format.
Use COLLADA when a scene, not just a mesh, needs to move between two older authoring tools that both implement the schema.
Convert DAE to glTF for anything shipping to a web viewer, game engine or AR platform today, since that's the format those targets expect.
AC3D to COLLADA questions people ask#
What software creates AC files?
AC files are written by AC3D, a modeller used mainly for flight-simulator aircraft and scenery. FlightGear loads .ac files directly as its native model format, which is why so much of that content exists as AC files.
Is an AC file the same as AC3D or ACC?
An AC file and an AC3D file are the identical format under two spellings of the same extension. ACC is close enough that the same parser reads it, but it adds one extra surface type for triangle strips that TORCS and Speed Dreams use for smoothing and shadow mapping.
Does an AC file support animation?
No. An AC file describes static geometry, materials and an object hierarchy, with nothing for bones, skinning or keyframes. Anything animated has to be handled outside the format, which is one reason AC models get converted to formats like glTF for modern use.
What is a DAE file?
A DAE file is a COLLADA document, an XML-based interchange format created at Sony Computer Entertainment in 2004 and now maintained by the Khronos Group. It describes a full 3D scene, geometry, materials, lights, cameras and animation, so it can move between authoring tools that don't share a native format.