It’s been a long road for the Synaptic A220. The project was first announced more than 4 years ago, went through a significant partnership with iniBuilds, missed its hoped-for 2025 window, and has since become one of the most anticipated aircraft in the MSFS community. As 2025 closed out, the team reiterated that the extra time was being used to deliver a more complete, polished product. Now, in the latest iniBuilds development update, the team says the A220 is “steadily progressing towards release-candidate readiness” and is “just about ready to enter the final stages of testing at the end of the month.”
For a project that has been in development this long, that’s a major statement. And if the technical detail shared in this update is anything to go by, the wait may well have been worth it.
The headline from the technical side of this update is scale. The team says the codebase has now grown to several hundred thousand lines of Rust and TypeScript code, covering 985 modelled components, 1,026 electrical connections, and 427 data buses including ARINC 429, AFDX, analog, and discrete. Those are numbers that hopefully reflect the kind of depth that puts this project in a different bracket from most add-on aircraft.
Since FSExpo 2025, core systems have seen serious development strides. The fly-by-wire system has been completely reworked, joined by a custom engine model, lateral and vertical flight guidance, autopilot, autoland, and fully featured electrical, bleed air, hydraulics, and radio systems. The flight management system was rebuilt from the ground up, with the team saying the goal was tighter coupling with other aircraft systems, better performance, and a reduced risk of fatal errors.
That FMS rebuild has enabled some genuinely intricate behaviour. The team mentions automatic nav-to-nav transfer on approach and the transition from DMC to PFCC guidance during autoland as examples of things that are now possible because of how the FMS integrates with the rest of the aircraft.
The crew alerting system is another area getting serious attention. According to the update, Synaptic monitored the actual logic used in the real A220’s CAS to create their own code that triggers messages with accurate input conditions, activation logic, and timing delays matching the real aircraft’s 100ms precision. The system currently has 3,350 different inputs routed through the data concentration unit module cabinets, and the team says they are still working through filling in the missing inputs.
The work-in-progress screenshots shared alongside this update give a good sense of where things stand visually and systems-wise. The cockpit is clearly well advanced, with all major displays populated and functioning, including the FMS pages, the PERF and ROUTE functions, and the lateral and vertical map displays.
One screenshot shows a night approach with the PFD and ND both active and the approach chart overlaid on screen. Another captures the full-width instrument panel, showing the characteristic wide-set screen layout of the A220 cockpit. The FMS close-ups show FPLN and ROUTE pages with detailed constraint entries, crossing altitudes, and speed restrictions, all of which suggest the guidance systems are well along.
This is a team that, by their own admission, has spent sleepless nights chasing rabbit holes in the real aircraft’s systems documentation. The model was rebuilt from scratch using 3D scans and technical diagrams, with texturing handled by iniBuilds using the same techniques applied to their A350.
There’s no release date confirmed yet, just the end-of-month reference to entering final testing. Given the history of this project, it would be unwise to read too much into timelines. But the tone of this update feels different from previous ones. There’s less hedging, more specificity, and the screenshots look like a finished aircraft rather than a work in progress, even if the watermark says otherwise.
We’ll be keeping a close eye on this one. When more information becomes available, we’ll have it here.
