fgdata/Aircraft/Instruments-3d/flap-ind/flap-indicator.xml

<?xml version="1.0"?>

<PropertyList>

 <path>flap-indicator.ac</path>

 <animation>
  <type>material</type>
  <object-name>Face</object-name>
  <object-name>Needle</object-name>
  <emission>
   <red>1.0</red>
   <green>0.2</green>
   <blue>0.0</blue>
   <factor-prop>/sim/model//material/instruments/factor</factor-prop>
  </emission>
 </animation>

 <animation>
  <type>rotate</type>
  <object-name>Needle</object-name>
  <property>/controls/flight/flaps</property>
  <factor>50</factor>
  <offset-deg>0</offset-deg>
  <center>
   <x-m>0</x-m>
   <y-m>-0.01</y-m>
   <z-m>0.01</z-m>
  </center>
  <axis>
   <x>-1</x>
   <y>0</y>
   <z>0</z>
  </axis>

 </animation>

</PropertyList>