Ok,

given the coments by Geofa, i decided to download XP10's latest demo (10.21 I believe...). As Geofa suggests, at least for the test situations he ran, the torque bug might have been fixed (?) This is strange because I think such a positive change should have been announced by LR. Probably - but that I will find sooner or later - the default aircraft were tunned to lessen the effect of troque-induced roll(?)
I would like to see this, preferably if not done through the use of artificial stability....

Going to the XP site I was surprised to find with the download the links for 5 nice aircraft. I knew about them all, and had tested the Robin. Downloaded all of it...

X-Plane10 installer is progressing, and I will test it tonight when I arrive home, and post here my findings :-)

As you all know, I went back to the ESP platform, and I am also a great fan of what I already consider the best flight dynamics ever made available for the PC - those that come with DCS World, but I can easily recognize the strong points in XP10, even if I gave up on it ...

A list of items that we can NEVER have in FSX / P3d (current version), but we can have very acceptably modelled in X-Plane:

1) Asymmetric thrust effects on aircraft with multiple engines distributed about their span... MSFS / P3D do a very poor job here, XP shines way above them. It's a limitation intrinsic to MSFS's flight dynamics model. Unless you feed ESP with an externally calculated flight model (apparently the new Q400 is using JSBsim to do it ?) you will allways, no matter how high quality add-on you use, be tied to the very poor asymmetric thrust effects of MSFS.

My two preferred FSX add-ons, PMDG's 737 NG and A2A's b377 are among those which use the MSFS core flight dynamics model and suffer from this rather unrealistic and annoying limitation. Of course if you do not plan to train engine-out scenarios, no problem...

Reciprocating engine models: MP vs RPM relationship and the Lean Bug!  These two kill the realism in any prop model in the ESP platforms. The first is responsible for unrealistic relation between MP settings and prop settings, althou extarnal calculations can be used, together with gauge programming, to mask the effect (A2A does it). The simplest for of the bug is present on any prop aircraft when you vary your prop RPM and see no coherent variation in MP on normal aspirated engines. The leaning bug has variable degrees of intensity depending on the pressure altitude, but basically the higher you go the more you will see that when you lean your mixture the FF initiallly increases and only after a while starts descending, as it should right from the start. You may not notice this at lower altitudes, but it becomes evident starting 4000' ...

Rotary wing aircraft are of course a LOT better in X-Plane than anything that can be done for the ESP platform, including the great DODOSIM Bell206...</p>

Sometimes I come here to say that MSFS aircraft sideslip and fwd-slip as well. This is true, but in order to make the effect more realistic in the ESP platform, the designers have to give away something in terms of yaw rates /forces... It makes the best aircraft add-ons for the ESP-based platforms require way to much rudder input to coordinate turns than in RL, particularly on aicraft that are known as "feet-on-floor" or almost, during turns...

Turbulence / shear effects - Yes, MSFS with good weather injectors, like the one I am using - AS2012 SP2 - and some add-ons (Accu-Feel, Ezdok, etc...) can do a good work, but still not up to the level of X-Plane!

Ok, I'll report latter my demo findings, and, who knows... I'll end up having to buy it again :-/

 

Well,

 

a few tests revealled that, at least on my side:

 

1) roll due to torque still present and excessive...

2) veer due to even moderate winds as soon as you release parking brake still present...

 

Well, I'll keep waiting for 10.30 :-)

10.30+ beta cycle will be the best :good:  :Love:

This torque issue is very strange then.....

This torque issue is very strange then.....

Well, it certainly must be (after all, Austin wasn't able to solve it yet...), and I do not have the original (pre-10.21) files anymore, so I can't say for sure that they didn't do some tweaking with the C172, the Baron etc... that could certainly account for a different feel as you described.

 

I do see trim tab settings on all of these models, and the C172 has allways been the aircraft that shows the less effect. OTOH when you "cut" the engine it developes a right banking tendency, and while this is acceptable due to the fact that under such circumstances and in RL various factors concur to produce it, namely what can be called negative torque (force that the engine cranking exerts to counter the force applied by the airstream on the windmilling prop), it is way too pronounced because indeed what is happening is that the trim tab set for climb / cruise flight regimes is now producing to much effect...

 

If you pick the Columbia 400 you'll see the "torque bug" really showing it's effects...

 

Also, none of these prop aircraft present credible sideslip angle due to asymmetric slipstream at high power and slow speed / high AoA regimes...

 

Austin will eventually solve this, so I hope. I had guessed it might be solved around 10.30, or at least be addressed as valid around that time, when other aspects of the simulator get more stable, but I believe they have so many things to deal with right now that it may not happen as of 10.30...

 

I will wait and see. If I ever see an hint of this being finally addressed, as well as the ground handling under wind (even faint..) I will probably reconsider X-Plane10.

 

It was nonetheless rewarding to run it again.. I missed those night lighting effects ;-)

 

P.S.: Just for the sake of completeness regarding my comments on this subjects...

 

Do the MSFS prop aircraft perform better? Yes and No... Yes because although they do have roll-torque too, they take into account, among other factors, dynamic pressure as speed builds up and counters any such prop effects (and probably even other balancing forces...)... No because they also do not model asymmetric slipstream, and use P-factor to somehow try to overcome such limitations, and also because they aren't near perfect when it comes to turns / sideslips with a balance between being able to sideslip and having to use way to much rudder to coordinate your turns being the result...

 

Is there a simulator where these effects are (at least as far as I was able to tell) correctly / very acceptably modelled? Yes - DCS World :-)

The p51d really nailed down all of the prop effects in that sim, as well as flight beyond normal envelope, sideslips and forward slips etc...

From some info I've seen, the Cessna has a hidden second rudder below the normal rudder. Jan. discussion at X-aviation. This would certainly have effects when engine is off. That thread didn't continue for long. As to FSX slips, RealAir has always done a very convincing job with them. I like their slipstream effects too. They work well enough for me. Those effects are usually what I test first. Afterall, the effects were quite pronounced on the real planes I flew.

I am talking about normal level flight. No longer is there the constant aggressive rolling to the left/right which needed constant pilot interaction, the "twitchyness" is gone, and so is the constant pitch hunting. I can now actually trim the aircraft for level flight, take my hands of the yoke and get reasonable stability-actually even better than fsx. This with the stability sliders all the way to the left! 

No more aileron trim to maintain straight and level...and the perception of being in air is very credible. It is a very significant change for me and what has me back using the sim again.

 

Now if I could only get a Reality xp like gps for 64 bit, or even get the 32 bit to work with my desktopaviator wonderful gps hardware unit I'd have something real useful for rw ifr training which is really all I use a sim for now.

 

 

No more aileron trim to maintain straight and level...and the perception of being in air is very credible. It is a very significant change for me and what has me back using the sim again.

 

I'll keep testing, and trying to find more about possible modifications, and will report my findings. I have to accept your observations as valid, so, there must be something (?)

 

And, it would be really great news if X-Plane10's flight dynamics model was finally able to iron those problems. I want to believe this wiil happen before the X-Plane10 cycle ends!

Ok,

 

it does feel different, I have to agree to some point :-/ !!!!

 

I'm going to bed now, but tomorrow will continue testing further. I believe it may well be related with better RoG calculations, etc... The core probably didn't change, but the aircraft parameters did...

 

Sorry for the initial comments... :-(

Ok,

 

it does feel different, I have to agree to some point :-/ !!!!

 

I'm going to bed now, but tomorrow will continue testing further. I believe it may well be related with better RoG calculations, etc... The core probably didn't change, but the aircraft parameters did...

 

Sorry for the initial comments... :-(

Goodnight flyboy :lol: sweet "simming" dreams

Thx FIVE-BY-FIVE :-)

 

It does feel different, and it's running really smooth on my system too...

 

The tests have now been made with all GA moels and under different weather scenarios.

 

I feel like a :Clown: regarding my initial comments :-(

I was feeling like an  :Clown: because no one seemed to have commented on these changes that to me are huge and earth shattering! :lol:

Well if nothing else, this conversation has convinced me to go back and fire up the demo again and update it.  I keep going back and forth on at least buying the regional version and picking up one good payware plane to give it a fairer trial, but the flight behavior of the default GA planes had really put me off and I'd pretty much decided - not yet.

 

Geof, what do you fly in XP?  What would you (or anyone else who cares to comment) recommend for GA - complex piston single and/or twin - to give this a better trial?

 

Scott

I especially like the bonanza by Carenado though I like most of their fleet. They are currently updating their aircraft for xp10- 3 already out the door.

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 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 :-)