Learn how to create flight simulator add-ons: choose an SDK, build aircraft, scenery or plug-ins, test cleanly and package files correctly.
To create flight simulator add-ons, choose one simulator and one add-on type, use that simulator’s official SDK and package format, build the assets or code, then export or compile, test and package the result. Start with a repaint, simple scenery object or small script before attempting a complete aircraft or complex systems plug-in.
Add-ons are simulator-specific. Microsoft Flight Simulator, X-Plane, Prepar3D, FSX and Flight Simulator 2004 use different file structures, APIs and build tools; a package made for one will not normally work in another.
Which type of flight simulator add-on should I create first?
A repaint or small scenery project is the most manageable first add-on because it teaches file structure, asset export and packaging without requiring a complete flight model or systems simulation.
| Add-on type | Suitable first project | Main skills required |
|---|---|---|
| Repaint or livery | One new colour scheme using an authorised paint kit | Image editing, texture formats and configuration files |
| Scenery | A landmark, hangar or small airport correction | Object placement, textures and optional 3D modelling |
| Aircraft | A basic conventional aircraft with limited systems | 3D modelling, animation, flight dynamics, sounds and systems |
| Plug-in or utility | A small command, display or data-reading tool | Programming, debugging and the simulator’s API |
A complete aircraft is several projects joined together. The external model may load correctly while the cockpit, animations, flight model or sounds remain unfinished, so divide the work into testable components.
Do I need to know programming?
You do not need programming knowledge for most repaints or basic scenery, but plug-ins and sophisticated aircraft systems usually require it. Some simulators also use scripts or structured configuration files, which are easier to learn than a compiled programming language but still demand careful syntax and debugging.
What tools are needed to make an add-on?
The required tools depend on the project, but most creators need the simulator’s SDK, a text editor, image-editing software and an archive utility. Aircraft and custom scenery may also require 3D modelling, audio editing, exporters and source control; our breakdown of practical add-on development tools explains what each category does.
Always use the SDK and exporter intended for the exact simulator release you are targeting. Microsoft Flight Simulator 2020 and Microsoft Flight Simulator 2024 both use project-and-package workflows, but creators should not assume every compiled package or SDK feature is interchangeable; our Microsoft Flight Simulator SDK setup walkthrough covers Developer Mode, projects, builds and package testing.
X-Plane plug-ins connect to simulator functions through its programming interfaces, so understanding how datarefs and commands expose X-Plane state is essential before writing a complex utility. Older simulators require their own matching tools too: the FS2004 SDK workflow and supported add-on types show why legacy compilers and exporters cannot simply be replaced with modern equivalents.
How do I build a flight simulator add-on?
Build the smallest valid package first, confirm that the simulator loads it, and add one feature at a time.
- Choose an exact target. Record the simulator, release, operating system and add-on type. Avoid trying to support several simulators from one untested package.
- Install the matching SDK. Read its sample projects and packaging rules before creating assets. Samples reveal required metadata, folder placement and naming conventions.
- Create a separate source project. Keep editable models, layered textures, scripts and documentation outside the simulator’s live add-on directory. Use the live directory only for test builds where practical.
- Make a minimal working version. This might be one placed scenery object, one livery, a basic aircraft model or a plug-in that reads a single simulator value.
- Export or compile it. Use the simulator’s designated exporter, compiler or package builder. Read warnings rather than assuming a successful build means every asset was included.
- Install it like an end user. Copy only the distributable package to the expected add-on location, restart the simulator and verify that it appears without relying on files elsewhere on your computer.
- Test each addition in isolation. Check models, textures, animations, sounds, controls and configuration changes after each build. This makes the last change the first place to investigate when something breaks.
- Prepare the release archive. Include only files users need, plus installation, dependency, compatibility, credit and removal instructions.
Why does my add-on work on my PC but not elsewhere?
An add-on usually fails on another computer because it depends on an unbundled file, an absolute local path, the wrong folder structure or content that happened to be present in the developer’s installation.
- Extra folder nesting: opening the archive should expose the expected add-on root, not another identically named folder before the real package.
- Missing assets: confirm every referenced texture, model, sound and configuration file is included with the distributable build.
- Local dependencies: remove references to development folders, private libraries or other add-ons unless the dependency is documented.
- Case and naming errors: inconsistent capitalisation may go unnoticed on one operating system but fail on a case-sensitive file system.
- Wrong build target: compiled plug-ins must match the simulator, operating system and supported processor architecture.
- Stale test files: delete or disable earlier copies so the simulator cannot load an old package instead of the new one.
A mistake we see constantly is testing with dozens of unrelated add-ons enabled. Test once with only your package active, inspect the simulator’s build or loading messages, and then repeat with likely conflicting add-ons.
How should I package and share the finished add-on?
A release package should contain a clean distributable build and a short readme identifying the simulator, supported release, installation location, dependencies and uninstall method.
- Do not include source caches, temporary exports, test screenshots or duplicate builds.
- State whether the package overwrites files; replacement of default simulator files should be avoided where an add-on package can override them safely.
- Include a licence for your own work and credit contributors.
- Do not redistribute simulator files, payware components, models, textures or sounds without permission.
- Extract the finished archive into an empty folder and install from that copy as a final packaging test.
PC add-on packages cannot normally be copied directly to console editions. Xbox and PlayStation users generally receive add-ons through an approved in-simulator distribution route, where one is supported, rather than through manually installed ZIP files.