SeligSIM (FS One) model flying simulator

My subjective summary first:

Presumably the most realistic simulator for model airplanes – consequently no helicopters.
Most sophisticated models and environment – yet a tool for learning to fly.
Glider and power aerobatics – especially distinct 3D aerobatics.
Slope and thermal soaring – in highly realistic wind and thermals.
Winch launch and aerotow – highly realistic towline.
Both ends of aerotow – one or both of the pilots on the controls.
No own models doable – but typical models of each category.
Pylon racer, scale, warbirds – maybe more but I forgot.
Really a lot of parameters can be modified – and models can be easily scaled.
The whole simulation environment can be customized – with the Power Tools.
Various tools for display – and 75 different camera views.
No flying over the Internet – no water flying either.
It gets better and better – and it's free.

This is a late entry in the list of model flying simulators actually used by me, and it's a special one. The simulator has been developed since 2003 so now it's a well-engineered and field-proven product. Something is new, though.

It's main author, Michael Selig, actually needs no introduction in the model-flying community. (Still you may search the internet or look at his personal website.) Now in retirement, he decided to shed the hassles of selling and supporting a commercial product and offer it for free download and usage (but a donation is welcome of course). Consequently, he dropped any helicopter simulation to focus on his main interest: airplane aerodynamics. The need to use a special controller was removed by using the standard MS Windows USB game controller interface. The new, free version was called "FS One 2022" (it came out in 2022) and later SeligSIM 2024 (it was renamed in 2024). It is offered and supported through the renovated SeligSIM website. The SeligSIM user manual is available online.

From the outset, I had seen FS One as the most realistic simulator for model airplanes. I just couldn't do with it what I needed a simulator for: develop own models and research their aerodynamic characteristics. It wasn't expensive but cost still too much to just try it for fun (I'm cheapskate) and I didn't want to dissipate my energies either so I kept to REFLEX XTR² (see previous page).

In early September 2022, I was kindly nudged by a message from Michael Selig that he had even met my wish for the game controller interface so I could use my wireless adapters. I would have tried FS One now anyway and had already noticed the news from the special thread in the Simulators forum at RC Groups. There, a list of updates is maintained and help is given to connect various types of controllers and transmitters as well as interfaces. Announcements and news are posted there (scan the latest posts); more information, pictures, and videos are in the special newsletter and the YouTube channel.

What more could you wish for? For me, there was no problem installing the simulator but I had trouble connecting my transmitter via its wireless adapter. With Michael Selig's help I succeded and learned about formerly unknown limitations of my devices. The simulator worked smoothly "out of the box" and probably could be fine-tuned to look even better, but that's not really needed. What is needed, however, is familiarizing myself with the endless options and parameters available to adapt the whole environment (airplane, scenery, weather, view) to my liking or the task at hand, respectively (see Features at the SeligSIM website).

So, having REFLEX XTR² in the first place to build and explore my own airplane models as well as to learn and practice flying helicopter models, what do I use SeligSIM for? Of course for other things it can do better:

Trying to fly 3D maneuvers, even though I'm not really into it.
Especially the 3D models in SeligSIM are most realistic so I can be sure that the model's behavior – good or bad – is caused by my stick inputs (and not a simulator artefact). I'm surprised to find out that especially 3D models can do "true" spins and snap rolls, that is driven not by aileron input but by autorotation, initiated and sustained with elevator and rudder only. And they do it even cleanly, that is with a controlled exit. I just see only "false" spins and snap rolls (flown with ailerons) in reality (of model aviation) so seeing "true" ones in virtuality is an interesting experience. This simulator can reliably provide it without needing and risking a real 3D model.
Enjoying various ways of soaring, what I really like.
Both "slope razors" and thermal floaters are most realistic and – equally important – wind fields and thermals are quite realistic as well. There are spectacular places to fly. While I basically have all that in the other simulator (but no winch launch and aerotow), it makes a difference (a better feeling) to know that all is as realistic as it can get. This simulator can provide this feeling and lots of good flying while in reality I don't have such places and the weather conditions neither (and consequently no such models).
Practicing both ends of aerotow, what I always wanted but had no chance to do.
Not only the airplanes are most realistic but the towrope as well. It can even be customized to more stiff or slack characteristics, to different strengths, and to different lengths. So either it's easy to break the line (or even the airplane) or the tow feels mushy and is hard to control. This way it's possible to try extreme situations in aerotow and get a feeling for how the towrope should ideally be (and an overload breaking part), in addition to practicing aerotow as such (even as a team). This simulator not merely replaces real aerotow by a cheaper and more convenient virtuality, it's the only practical way to try extreme and dangerous situations without wastage of precious models.
Trying to fly glider aerobatics, what I always wanted to do but not in reality.
Again the airplanes are most realistic but now something technical, simulator specific is required in addition: The simulator's view ("camera") is highly customizable, including auto-zoom, so the glider is nearly as well visible as in reality even though it's rather high (far away) during an aerobatic schedule. This simulator makes trying glider aerobatics possible at all (by suitable camera views) and does it trustworthy (due to realistic models) while just trying would mean far too much cost and effort in reality.
Trying to fly FPV while I'm not sure if I'd even like to do that in reality.
There are some quite nice so-called 3D flying sites where FPV is possible, and there are reasonable ways to "look around" in the simulator (though still not as easy as by VR headset with 6DOF like used in reality). It's even possible to display several flight data (altitude, speed, and more) similar to special onboard displays used in FPV flying. This simulator is just a cheap way to try (and practice in case I like it).

That's a schedule for months if not years and it's only my field of interest. I could easily imagine more things that could be explored with SeligSIM so think further. It can't do everything but what it can do it does extremely well.

It can also be a good learning and practicing tool. For that I have the other simulator but others may not, and SeligSIM is even free! You might read my paper about learning to fly with a simulator (here); the general assertions apply to SeligSIM, too.

Finally, I could imagine things which could not be explored with SeligSIM as is but which I would like to explore. They would require elaborate extensions. For instance, I'd like to explore the stall behavior of a marked STOL airplane (the Dornier Do 27) or the various effects that contribute to left-yawing tendencies of propeller-driven airplanes (including twin-engined). That would require "building" such airplanes in the simulator and developing mathematical models for their special aerodynamic elements (flaps, slats, propellers).

That's Michael Selig's special faculty but then again it's his fun to develop the simulator so he must follow his interests. I'll thankfully enjoy what he gave us so far and work through the schedule listed above.