Extending custom classes in AS3?

1

im trying to port my code to as3 but i stumbled on a problem i have no idea how to fix.
error report:


verify PointAirFri$iinit()
                        stack:
                        scope: [global Object$ Point$ PointAirFri$] 
                         locals: PointAirFri Number Number Number 
  0:getlocal0
                        stack: PointAirFri
                        scope: [global Object$ Point$ PointAirFri$] 
                         locals: PointAirFri Number Number Number 
  1:pushundefined
                        stack: PointAirFri void?
                        scope: [global Object$ Point$ PointAirFri$] 
                         locals: PointAirFri Number Number Number 
  2:setslot 14
                        stack:
                        scope: [global Object$ Point$ PointAirFri$] 
                         locals: PointAirFri Number Number Number 
  4:abs_jump 78424138 45
                        stack:
                        scope: [global Object$ Point$ PointAirFri$] 
                         locals: PointAirFri Number Number Number 
  0:getlocal0
                        stack: PointAirFri
                        scope: [global Object$ Point$ PointAirFri$] 
                         locals: PointAirFri Number Number Number 
  1:pushscope
                        stack:
                        scope: [global Object$ Point$ PointAirFri$] PointAirFri 
                         locals: PointAirFri Number Number Number 
  2:getlocal0
                        stack: PointAirFri
                        scope: [global Object$ Point$ PointAirFri$] PointAirFri 
                         locals: PointAirFri Number Number Number 
  3:constructsuper 0
VerifyError: Error #1063: Argument count mismatch on Point$iinit(). Expected 3, got 0.
    at PointAirFri$iinit()
    at docClass/::init()
    at docClass$iinit()

this is how the defined the classes:

package{
public class Point
{
    vars
    public function verlet(a)
    {
        code
    }
    public function savePoint()
    {;
        code
    }
    public function restore()
    {
        code
    }
    public function Point(__x:Number, __y:Number, __fr:Number)
    {
        x = __x;
        y = __y;
        dx = 0;
        dy = 0;
        vx = 0;
        vy = 0;
        friction = __fr;
    }
}
}

package{
    import Point;
    public class PointAirFri extends Point
    {
        private var airFriction;
        public override function verlet (a)
        {
            code
        }
        public function PointAirFri(__x:Number, __y:Number, __afr:Number)
        {
            x = __x;
            y = __y;
            dx = 0;
            dy = 0;
            vx = 0;
            vy = 0;
            airFriction=__afr;
        }
    }
}

if anyone has any idea why that error happens please enlighten me:)