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jcomm

Has the core FDM changed?...

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In a short and concise word - NO!

 

Well, here's what I found and how...

 

Since I bought X-Plane10 a 2nd time, I decided to install a native version (10.03r2) which came with my DVDs of Global Edition, and used that one to determine the differences between the original Baron 58 and the one in 10.21, which feels a lot more stable regarding the unfamous "torque bug", but also apparently more stable in terms of trimming.

 

Well, to go direct to my findings, if you pick the default Baron 58 from 10.03r2 and load it in 10.21, be sure to experiment exactly the same rolling tendency that we used to see in that model and other defualt prop aircraft in X-Plane10. It will make that "torque bug" shine on your face!

 

So... the "secret" lies in the editing that that model, and others, have received in between.

 

What does tis proof?

 

Well, to me it proves that we have pretty much the same core FDM (less the changes made to Plane Maker between 10.03r2 and 10.21), and somehow the thesis that a well designed aircraft, with precise data being used, will give a much better outcome.

 

Does it mean that after all, X-Plane10 FDM is right about thye way it renders prop torque effects? I don not think so, but probably it requires a lot less tweaking than I supposed, and after all, an amount of torque roll is also present in MSFS, and even in JSBSim...

 

Today I was reading the positive exclamation of a Q400 user (in FSX) saying - "One thing I noted right off the bat is you will definitely need to use right aileron trim!"...

 

Well I promptly posted a reply explaining it shouldn't really be that way, and it only happens like so because that Q400 is using an external FDM based on JSBSim (one of the FDMs used with Flight Gear), which is also limited in respect to modelling the other aerodynamic/mechanical  effects that lessen the torque-induced roll on most prop aircraft...

 

Finally, I also found, by running 10.03r2 and 10.21 at the same airport and time of the day that, contrarily to what I was thinking, nothing changed either regarding the daylight near Sun set / rise... Probably it's related to the time of the year, I do not know, but right now it looks a lot better than during Autumn / Winter...

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In a short and concise word - NO!

 

Well, here's what I found and how...

 

If you were next to me right now, I would smack you :lol:  :P just fly and have fun.  For me, the best Flight models are Peter's Airbuses in XPX64.   :good: Even Peter's SOUNDS are amazing and it really sounds like your in the plane.....I have not heard this before in any other payware.

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But I am enjoying it ;-)

I will fly you to Canada just to smack you and then send you back to Europe on return flight same day :lol:  :lol:

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Ok!

 

I have a great portuguese friend nearby Toronto. He's been there for more than 30 yrs!  Never met him personaly, but I did meet his mother when she visited Portugal.

 

I worked with him on the first scenery for the Azores, for fs4 (yes, not 2004!!!). We also cooperated with Manfred Moldenhauer back then with his SCASM BGL compiler, as well as with Enrico Schiratti and Maurizio Gaviolli :-)  Those were really very Good times!!! Smack me FIVE!!!! :-)

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Airplane torque has been an interesting subject for me; lately. I wasn't sure , of the exact reasons it's not a big deal after the wheels leave the ground, with the exception of slow airspeeds and high power.

 

I've talked to a lot of pilots, about a lot of airplanes . And then I have my own experiences with lots of torque on the takeoff roll, but much diminished once airborne.

 

I've tried all kinds of combinations of torque and roll, and airplanes on Google. When the subject of reining in torque is discussed....... It's going to include X-Plane as part of the subject matter. You can count on it. These discussions are on and off postings for the lastf four years. There are articles about the need to trim and retrim for torque, while on the climb or power changes in cruise . For instance, the MU2; but when you get to the heart of it, it's an XPlane discussion and not a real pilot report of an airplane flight. Letting go of the yoke and noticing some roll to the right, isn't the same as a need to trim out roll forces on the climb. This was about the MU2, which rolls right instead left. The comment doesn't include the force or speed of this roll effect. You don't even see the matter discussed as part of the takeoff sequence in actual pilot reports. It's always about yaw. Aileron trim is just a secondary function, to clean everything up, for hands off flight, if you have aileron trim to begin with.

 

In so many words, this need to trim out a tendency to stop a rolling motion after takeoff is an X-plane thing, that's differing from the real world. It's just an overdone effect........that's not like the real thing.

 

Someday, I need to find out how to get a new password with a different email address. Typing this with one finger is too munch.

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