Plane is not controlled in the air at SITL Gazebo

I am developing my own aircraft, but before the physical tests, I would like to simulate it in Gazebo. And I ran into several problems:

  1. Gazebo does not describe the physical properties of the fuselage, including the wing. After unloading your model from SOLID to .stl format, and then converting to .dae format, this file contains only airframe visualization without any physical properties.
  2. Description of plugins in the .sdf file. When substituting your recalculated data cda, cla, etc. the device absolutely does not obey its controls.
    My parameters:
<joint name='elevator' type='revolute'>
      <pose relative_to='base_link'>-1.53563 -0.001001 0.037729 0 -0 0</pose>
        <xyz>0 -1 0</xyz>
    <link name='Link5'>
      <pose relative_to='elevator'>0 0 0 0 -0 0</pose>
        <pose>0 0 -0 0 -0 0</pose>
      <collision name='Link5_collision'>
        <pose>0 0 0 0 -0 0</pose>
            <scale>1 1 1</scale>
      <visual name='Link5_visual'>
        <pose>0 0 0 0 -0 0</pose>
            <scale>1 1 1</scale>
<plugin name="elevator" filename="">
      <cp>-1.536 0 0</cp>
      <forward>1 0 0</forward>
      <upward>0 0 1</upward>

Thanks for any help.