Foro x-plane.es

Foro General => Aircraft-Plane-Maker => Mensaje iniciado por: jorduran en 22 Agosto, 2012, 18:23:50



Título: Para los creadores de aviones
Publicado por: jorduran en 22 Agosto, 2012, 18:23:50
Aqui va una información de Austin explicando el porque vuelas diferentes los aviones con la nueva version

IMPORTANT TECH NOTE

The new supersonic model going into X-Plane 10.10 now, like ALL of the dynamics in X-Plane, considers all of the various bodies that you have created for the airplane.
That is: ALL of the fuselage, misc bodies, nacelles, etc, are considered to be exposed to the airflow.
This means that if you have multiple bodies one inside the other, the aero effects will be DOUBLED compared to reality!
Also, if you have one body hiding right behind another, or behind the fuselage, then the drag effects will be DOUBLED compared to reality!
This is why with the latest beta, some planes are not going supersonic that should: We are now computing the drag more accurately on each body, and having multiple bodies one behind the other simply add up the drag based on the frontal area of EACH BODY!
A very simple case of this is an F-104 Starfighter model that uses a fuselage for the FRONT of the plane, and a misc body for the BACK!
In this case, the front of the misc body is acting like a big flat-plate exposed to the air.. surely enough to keep the plane subsonic!
So, to design a plane properly, do NOT use misc bodies and fuselage and nacelles stacked inside each other, or behind each other in a row.
This will simply erroneously add up drag!

When designing a plan e for X-Plane, the rule is really very very simple: Each fuselage, misc body, and nacelle has the local air aciting on it.
That's it!
So it is actually really simple.

Now, there is ONE exception: Engine nacelles for jets. Engine nacelles for jets are assumed to NOT produce any drag.
This is because the thrust for the engine that you enter in Plane-Maker is considered to already be based on installed thrust losses.

So, if you want your ACF model to be accurate, then do not have hidden-away misc bodies with frontal area inside another body, and certainly
do not have 2 bodies one behind the other to make a long body... the frontal area of the aft body will still be exposed to the air in X-Plane!

If you want really detailed geometry (read: more than you can get out of a body in X-Plane, so you want to hook multiple bodies together) then it is time to
build an OBJ for your airplane!

austin



Título: Re: Para los creadores de aviones
Publicado por: Cestomano en 22 Agosto, 2012, 18:27:23
mmmm, creo que con la C172 no tendré ese problema  :D