Fine-tuning the default aircraft in xp10...

[jcomm 5,938]

Fine tuning of the default aircraft in xp10, avoiding user license infringements, of course, is a nice way to spend our time while we wait for further flight dynamics core modifications from Austin... While he fights the patent trols (a fight I fully support) we can take our time to learn more about the rather detailled plane-maker (PM) editing potential...

 

A special THANK YOU to Goran who first pointed me some of the most interesting areas to explore in PM!!!

 

One area where I find most default aircraft fall short from being realistic is the response to some control inputs, like the rudder, for instance...

 

Take the default C90 and get to a cruise altitude of, say, 6000' at 215 KIAS (close to the published typical cruise speed for the normal C90). Now, kick the rudder all the way to the left/right and watch what will result from such an abrupt deflection... Most probably you will enter some sort of snap-roll and end-up inverted.

 

Now, I don't beilieve the real thing would allow for such agressive control inputs without first suffering from severe damage to the control links/surfaces, and I do not even believe the pilot could use the force required fro such a deflection at cruise speed, so, I suggest we tweak an interesting area of PM - Control Phase-Out.

 

Leave XP10 oppened, and start PM. We do not have the possibility of aircraft reloads on-the-fly in XP10 like we do in FSX, so, each time we cycle through a chnage we will have to load the C90 again and place it at 6000' and, say, 225 KIAS for the next test.

 

In PM open Standard / Control Geometry / Phase-Out and navigate to the RUDDER1 and RUDDER2 entries. There we will set, on the rightmost columns, a treshold speed of 200 kias to reduce rudder control authority to 20% of it's total effectiveness. In "hi-end speed (kias)" enter 200 for RUDDER1 and RUDDER2, and in the corresponding "high-end control travel (ratio)" 0.20 (= 20%).

 

Load the C90 again in XP10, bring it up to 6000' at 215 KIAS and move your rudder again, left and right... Does it feel better? It should... If not yet the way you would like it, before choosing to lower the "hi-end speed (kias)" or the "high-end control travel (ratio)" you can now experiment with the Raddi of Gyration (RoG) for the longitudinal (roll) axis and adjust it so that the yaw-induced roll is adjusted.

 

In PM open "Standard / Wheight & Balance" and navigate to the "RADDI OF GYRATION" section. The C90 being a twin has it's weight more distributed along the lateral (pitch) axis because of the two heavy PT-6A engines, so, instead of the default "radius of gyration in yaw" value, which you should store to rollback any changes to the standard values (it's easier with the Phase-Out mods because their defaults are all set at 000 and 0.00), use a value of, say, 015,00 (ft). Again, go test flying and load the aircraft, bring it to 6000' at 215 KIAS...

 

Repeat until you're tired or satisfied...

 

Do this every time you start having 2nd thoughts about XP10's torque-roll bug or poor ground handling, or absence of seasonal textures, or whatever turns to be a show stopper for you in XP10...

 

Enjoy

 

PULEEEZE!!!! Save all of your default PM values before starting to tweak, or make backup copies of the default aircraft files (the all folder) just in case you need it...

[jcomm 5,938]

And since I'm on these subjects, here's a link to a good explanation of MoIs and RoGs...

 

http://www.real-world-physics-problems.com/radius-of-gyration.html

 

We get the same formulae from many sources, and can convert between MoIs and RoGs provided we have, say, MoIs for a given good model in MSFS, at least as an aproximation...