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MSFS20 aircrafts / flight model

Hawk_101

Hawk_101

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26
Country
germany
Hello everyone, I'm new to this forum, hopefully here is the right place to ask
I'd like to modify 2- 3 aircrafts ( the flight model) and I'm not sure which values are the most important.
Could anyone, please, give me some tips, where to start?
The aircrafts I'd like to modify are :
Pitts Special - Asobo
F15C - 3rd party
Spitfire - 3rd party
When I fly them, I'd like to feel the weight, heaviness, a bit more elasticity, inertia, etc
Thank you in advance
 
Hawk on your post above you can set a drop-down box right at the top to say which sim you are using, e.g. FSX, MSFS, P3D. You mention Asobo in your post so it's clearly MSFS, but you can speed things up by making that clear up front.

The docs for flight_model.cfg are here. Also you might end up looking at engines.cfg

If you are new to this you will inevitably be too ambitious at first, underestimating how complex the interaction is between the parameters you can specify - the experience gained there gives you good clues of what to check in the behaviour each time you make a change.

A suggested hint to get started would be:

(1) enable developer mode in the sim, and look at all the debug/diagnosis screens

(2) Pick a single plane - at a guess the exceptionally aerobatic Pitts Special is the wrong place to start, but if you back it up carefully you can't ruin it.

(3) Create carefully stored copies of any file you will modify, include the date, e.g. flight_model_original.cfg, flight_mode_2021-0712.cfg.

(4) Choose ONE thing you think you might like to change (like Moment of Inertial in Pitch) and make adjustments to that (including search the internet for just that change) and get familiar with what you can do to measure the effect of your changes.
 
Thank you so much for your reply
Yes, whatever changes I'm doing, there is always a backup of the original file.
I know it's not easy, I do not underestimate this.
Pitts Special was just an example, that's an aerobatic aircraft
I know it's impossible but I'd really like to have the same ( almost the same ) flight model / aerodynamics, for the Spitfire, like the one from DCS World.
I'd pay 3 x the price of the aircraft, for this
 
I'm sure you'll get there, it's just quite a grind.

If it helps, the Asobo Cessna 152 flight_model.cfg has a comment next to each parameter which will provide more clues. Some parameters do NOTHING so that's not particularly helpful.

You can quickly make a plane more agile by increasing the up/down limits of the control surfaces (e.g aileron_up_limit)

The [FLIGHT_TUNING] parameters are a hack not liked by purists but they are a quick way of forcing your changes in to a flight model, .e.g pitch_stability - in general the changes you want should be possible by altering more 'fundamental' parameters elsewhere in the file but we all end up tweaking [FLIGHT_TUNING] parameters at some point (i.e. using values other than "1") including Asobo.

The parameters with moi (moment of inertia) in their name are fairly key, and have a massive impact on the feel of the aircraft.

The main 'gotcha' is tweaking one parameter often has a 'side effect' on something else you didn't think about - I develop gliders and they need the lift/drag ratio to be accurate at all speeds within a percent or so, and most parameters in flight_config.cfg affect lift or drag or both in some subtle way so that's my issue, but the challenge is there for everyone.

In something like a Spitfire it's possible you might want to mess with the flap settings (e.g. flap lift & drag) at some point you'll end up messing with the engine power and prop characteristics in engines.cfg to compensate for other changes you might have made in flight-model.cfg (i.e. after you 'correct' the flaps, the climb rate might be wrong).
 
Thank you, again.
I really appreciate your help and support
I'd like to ask you something, off topic, maybe you know the answer
I purchased ( Microsoft Marketplace ) the Waco for MSFS 2020, it's a great product but unfortunately I can't have access to the flight_model and engines files
Is there a way to create a fake mod, for this aircraft, to be able to edit the flight_model file?
 
lol I have not much of a clue - I haven't seen any 3rd party planes with encrypted content yet - I would guess the technique is to override Waco files in the virtual file system with your own, in this case the flight_model.cfg. You might not be able to get the content of the current flight_model.cfg to start with though. IMHO your question is worth a separate post under 'other', or you might get some response on the official MSFS forums...
 
I'm getting better and better, the aircraft ( Spitfire ) feels so much better, the difference it's huge
I'm trying to find a way to " compensate " some modified values. When I'm on the ground, the aircraft tends to " flip " forward ( I modified a bit, the weight )
It's very very difficult, as you said. But it's worth the time and effort.
 
Hawk_101 said:
When I'm on the ground, the aircraft tends to " flip " forward
Click to expand...
Do you mean the plane tips onto its nose when you are parked, or do you mean the nose tips down when you are braking on the runway after landing, or something else?

The quick thing to check is you haven't moved the "CoG" (center of mass) too far forwards - see here

If the center of mass is still in the right position and you're pitching forwards under braking, perhaps the contact points (in flight_model.cfg) are wrong (i.e. the wheels are too far back - the SDK screens have a debug screen that displays those overlaid on the plane.) Or maybe the brakes are stronger than they should be (there's a parameter for that somewhere) - are you applying the brakes on an AXIS (i.e. you feather the brakes in) or are you simply flipping the brake from 100% off to 100% on?
 
Yes, the aircraft tips onto its nose, when parked
I didn't touch the CoG settings.
Could you please tell me where exactly is this SDK setting " debug screen that displays overlaid" ?
If the wheels are far too back, which CONTACT POINTS setting is the right one, from the flight_model file?
There are many numbers / values
I tried to increase back the weight, closer to the real values, and after that, I increased the MoI pitch
By the way, do you modify the values elevator_elasticity_table or aileron_elasticity_table ?
I can't understand exactly what those are
Thank you so much for your help
 
ok one thing at a time.. did you find the screen that shows where your CoG is? (I included a screenshot).

If you did, maybe post a screenshot here (that would be best) or just confirm where the CoG is - i.e. is it in the right place, or is it too far forwards hence your issue.

When we're done with the 'tipping onto nose when parked" issue, it will be best to start another thread for a new issue...
 
I increased more, the weight and modified the MOI.
It looks okay now, it feels absolutely amazing, I can " feel" the aircraft now.
What about the question with

elevator_elasticity_table and aileron_elasticity_table ?
 
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