SITL Forge - FPV Laboratory

SITL Forge is a physics-first FPV simulator. Motors, props and batteries are fitted to real bench data, physics runs at 1000 Hz, and every airframe is a real-world design — from a 2" micro to a 13" cinelifter. Fly it, race it, build it — or plug in real Betaflight and iNAV firmware.Fly
Built-in Betaflight-style flight controller: ACRO, ANGLE, HORIZON, live PID and rate tuning

Race tracks with real-size gates and timed laps — practice or a 3-lap race

FPV camera with real lens distortion; any joystick or USB RC transmitter
Build
Swap frames, motors, props and packs in the workbench — weight, thrust, current and flight time recompute instantly

Detailed real-world airframes, 2" to 13", down to screws, cables and battery straps
Real physics
Motor losses, prop thrust and torque fitted to dyno data

Battery sag and heat, ESC limits, rotor inflow and ground effect, wind-tunnel drag
See everything
Live OSD and graphs for every variable — RPM, current, gyro, temperatures

Record and replay flights in 3D, export to CSV, import Betaflight and iNAV logs with the DLCs
Real firmware in 3 steps (optional DLC)
Swap the built-in controller for real Betaflight or iNAV running on your PC — same physics, real code.

Betaflight
Build the SITL from Betaflight source: make SITL_X_PLANE

Run betaflight_SITL_X_PLANE.elf

In SITL Forge: External FC → Betaflight → Activate. Betaflight Configurator connects to ws://127.0.0.1:6761

iNAV
Install iNAV Configurator — the SITL is already inside

In SITL Forge: External FC → iNAV → Activate

Run inav_SITL --sim=rf --simip=127.0.0.1 --chanmap M01-01,M02-02,M03-03,M04-04 — the one-time CLI setup is in the in-app guide