Aerofly FS4 Bridge DLL

Hi! I am very happy to announce that I finished my DLL project. It has plenty of documentation and I will keep adding examples.

I hope it is useful for the Aerofly FS4 community, for the moment it is only available for the Microsoft Windows 10/11 version of the simulator.

Here I open the discussion for comments, support and suggestions.

Now it is time to start building integrations or new applications with this, and for new developers to improve the DLL and build their own version for their project's needs, I hope this work can be useful to them. Happy flying!

Aerofly FS4 Bridge DLL Repository

Just wanted to add, that this release doesn't cover the controls.tmd variables from individual aircrafts.

As an example, I extracted some of these additional variables from the Cessna 172 controls.tmd file and added them to the DLL source code,as a reference for adding some others we may need.

So, at this stage, I think custom DLLs must be done for custom aplications, we still don't have a DLL that works for all the needs.

There are more than 5.500 variables defined in the controls.tmd files for all the aircrafts.

... and if someone build cool examples, I will be happy to include them in the examples section!

Hi Chris! good questions, forgot to comment. In the externall_dll folder the json file is generated each time you start the sim.

And if you export your variables from the same app, it will be saved there too:

I modified the GUI adding a comment at the footer and in the source code a comment. Thanks!

Hi Chris! here it is the answer from the new ChatGPT 5 model, that everybody is talking about. By the way, the timing was perfect, with it launch I could use it to finish the project. We will have time to talk about all these soon, thanks for your interest and tests.

Short answer: offsets are not per-user; they’re per-DLL build/version.

- Don’t hardcode absolute byte offsets like 2328/2336. They can change between releases as the struct/layout evolves.
- Instead, use the offsets JSON that’s generated next to the DLL. That file is the source of truth for that DLL version.
- Even better for shared memory: use the logical index approach from the JSON (array_base_offset + index × stride_bytes). The variable indexes (e.g., for latitude/longitude) are stable by name; we keep name→index consistent and append new vars at the end when needed.
- If you want maximum forward-compatibility, use the TCP or WebSocket APIs and read by canonical variable name.

So: all users with the same DLL build share the same offsets, but offsets can change across versions. Use the JSON (and/or index-based addressing) rather than fixed numbers.

Hi, actually I am reviewing the documentation and the examples from the tutorials. This will take some days, but you can follow the progress if interested. The idea is that all the examples work.

Hi, I was thinking, since the repository is becoming more an more an educational resource, and I keep adding tutorials, a nice way to teach young kids computing would be to do integrations with the sim, because it is very cool to see something you do and interact with the aircrafts.

I think kids would enjoy this so maybe Ipacs could offer the sim to schools to use it as a simulation and development laboratory.

The tutorials are AI generated, then I test them and fix errors. But first I generate them, upload them to the repository and later I test them.

So some of them will have errors, and will be fixed with time.

First tutorial tested and fixed.

A web instrument that shows a live airspeed tape with performance envelopes (white/green/yellow/red arcs) using canonical variables from the Bridge. Single HTML file, no frameworks.

Simple Tutorial #8: Airspeed Envelope Tape (WebSocket)

Hi Scott! thanks for your interest, you will see that it will be easy to integrate. Here it is Claude Sonnet 4 answer to your question:

Hello!

Great to hear you found our autopilot script useful and that the DLL bridge installation was straightforward. I understand the frustration with compiling from documentation - that's exactly why we created the precompiled DLL to make things easier.

Regarding your Aerofly broadcast configuration on 255.255.255.255:49002, that's indeed the native UDP stream from the simulator that you mentioned. However, our AeroflyBridge DLL works completely independently and doesn't interfere with that UDP configuration.

Our bridge uses three separate, independent interfaces:

1. Shared Memory (for high-performance local applications)
2. TCP Server on ports:
   • Port 12345: Real-time data stream (JSON)
   • Port 12346: Command channel (JSON)
3. WebSocket Server on port 8765 (default): For web/mobile applications

You don't need to change your UDP configuration of 255.255.255.255:49002 - that can continue working normally for your other scripts.

To connect to our bridge from your autopilot script, you should:

• Connect via TCP to port 12345 to receive complete JSON data (339+ variables)
• Use port 12346 to send autopilot commands to the simulator
• Or alternatively use WebSocket on port 8765 for both functions

The bridge will give you full access to all autopilot variables like Autopilot.Heading, Autopilot.SelectedAltitude, Autopilot.Engaged, etc., with bidirectional capability to read and control the autopilot.

Hope this clarifies the difference! If you need specific help integrating the bridge with your radio/map script, I'd be happy to assist.

Today I will review this tutorial to be sure it is working and fine, I think it may be useful to your integration.

Hi Scott, this one I think will be more useful to you. Tutorial and sample html file created on the fly, for the user specific requirement. We are really living in a technology revolution, I wonder how the years to come will be.

Simple Tutorial: Smart Radio Navigator (WebSocket)

Code for the example, just save it in your pc, run the sim with the DLL in the external_dll folder, and open the html webpage with your browser:

Smart Radio Navigator (WebSocket) html file

Two new tutorials were updated, with their source code files.

Don't take too serious what they do, they are just to explain with examples how to use the DLL.

Simple Tutorial: Co‑Pilot Checklist Dashboard (WebSocket)

Python Tutorial: Aircraft Tracker with Interactive Map (TCP)

Python Tutorial: Flight Data Logger (Python + JSON)

Quote from Jugac64

Hi Scott, this one I think will be more useful to you. Tutorial and sample html file created on the fly, for the user specific requirement. We are really living in a technology revolution, I wonder how the years to come will be.

Simple Tutorial: Smart Radio Navigator (WebSocket)

Code for the example, just save it in your pc, run the sim with the DLL in the external_dll folder, and open the html webpage with your browser:

Smart Radio Navigator (WebSocket) html file

Hi Scott, yes, please take a look at this one, here you will see how to read and write in the COMs and NAVs. I still have to review the one you tested.

In general, please only use the tutorial samples to look at the source code and get the idea on how to do your own integrations, they are not useful applications. For me, there it is not better way to explain things than with examples (at least in coding).