Ok,

 

so I didn't go to sleep... :blink:  but I managed to find out at least one of the reasons why (some of) the default GA folder aircraft feel so different.

 

I can't say the difference started 10.21 since last time I ran X-Plane10 before selling my copy it was a few versions before, but tonight, after experimenting with more aircraft, including the Experimental Vans, etc... and looking inside their "airfiles" I found an evident differences on the

 

- C172, C90, B58

 

These all have their Radii of Gyration manually tunned, as well as Control Phase-Out edited.

 

If you fly these aircraft you'll have to notice the effects of better set values from the default ones used on previous versions.

 

Is this bad news? Certainly not - none is using Artificial Stability, and that's good enhough for me right now.

Also, it somehow proves what I myself have used before to tune some aircraft, mostly phase-out since I never found a good method to manually set the RoGs with accuracy...

 

If you pick other aircraft, for instance the Vans RV-6, you will still have that "torque bug", but oppening those aircraft in PM will show that they aren't using control Phase-Out or customized RoGs.

 

Yet, I believe there is something different too even noticeable on those non-tunned models because as Goefa pointed out, it is somehow easier / more realistic to get them properly trimmed on an almost set & forget way during your flight, and this may indicate that something changed as well in the core FDM (?)

 

Well, I am more satisfied now because I believe I understood at least part of the reason why Geofa correctly stated that he finds aircraft in 10.21 behaving much better / diferently from previous versions :-)

your wife called me and told me to tell you:  "GET YOUR &@($* OFF AVSIM AND GO TO BED" :lol:    :girl_devil:

your wife called me and told me to tell you:  "GET YOUR &@($* OFF AVSIM AND GO TO BED" :lol:    :girl_devil:

 

:LMAO:

My Carenado aircraft though would not have been tuned?!...yet...but they work great again.

My Carenado aircraft though would not have been tuned?!...yet...but they work great again.

 

That is normal. Some Carenado aircraft use the Art Stab section to replicate the correct / expected behaviour regarding torque, yaw and roll rates, etc... They also have customized RoGs, and I don't recall, but probably controls Phas-Out as well :-)

Yes but they flew as poorly for the last 6 months until 10.20 came on. They haven't changed since day 1 when they flew well too, although now they are finally being updated.

Although some of the default aircraft were probably tweaked, I think something changed with 10.20.

I need to find Marty McFly and borrow his DeLorean to time travel in the future when Austin releases 10.30 beta cycle, that cycle will be amazing and full of great fixes.

 

I surely hope so FIVE-BY-FIVE !!!!  ;-)

At Flightsim com. we were working on the way in which X-Plane uses or doesn't use the prop blast from the right angled engine over the left wing, to offset torque. Modern designs use the offset instead of different wing incidences that had secondary effects of opposite roll, when power is pulled back. Have you looked into this?

At Flightsim com. we were working on the way in which X-Plane uses or doesn't use the prop blast from the right angled engine over the left wing, to offset torque. Modern designs use the offset instead of different wing incidences that had secondary effects of opposite roll, when power is pulled back. Have you looked into this?

 

Yes, but I no longer recall my findings :-(  I trashed all of my test notes of XP10 ...

 

It's clear from the FM display that XP calculates the effect of the asymmetric slipstream on the left wing (for a cw rotating prop) which is by itself very good indication of at least the propwash over that lift surface being calculated. Somehow, though, it does not correctly compute this and other effects that lessen the roll due to torque for instance as speed builds up (dynamic pressure).

 

On the tweaked default models there is no cant being used.

 

The use of control Phase-Out is nonetheless very efficient and a good way of overcoming the fact that X-Plane doesn't really calculate hinge forces on the controls. The aircraft behave a lot better because as IAS increases the effects of moving the controls wildly don't end up in such strange effects...

 

Also, XP10 models negative torque from a windmilling prop. The airflow exerts a force on the engine that this counteracts according to Newtons third law. The force will make the aircraft roll about it's longitudinal axis in the same direction of the prop rotation (to the right on a CW rotating prop...). MSFS, for instance, does not model this.

 

I agree with Geofa when he reports better / much better feel overall, but from my short examination I just noticed:

 

1) the modified aircraft have their Radii og Gyration manually input

2) some of them also have control phase-out set

3) some use trim tabs for ailerons and rudders

 

Appart from these, even on non-modified aircraft there is a different (less twitchy) feel, that I like :-)

 

I will NOT uninstall the demo ...

I may well return by 10.30... :-)

Larry, in the attached screenshot you can easily see the effect of the spiraling slipstream on the left wing, creating a higher resultant that will account for a roll to the right...

 

OTOH, the discontinuities on the lift / drag vector near the wing tips are not a nice thing to see on some models... :-/