stack overflow error #1007 and arrays in Actionscript3
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I looked through the search and couldn't find anyone with quite the same problem so here goes.
I'm trying to make a side scrolling shooter and am generating all enemies with code instead of placement and I keep running into:

'TypeError: Error #1007: Instantiation attempted on a non-constructor.'

Relevant Code:

    tanktimer++;
    var n:MovieClip;		
    var lv1arr:Array = [24,120,144,264,288,384,408,432,480];						
    var lv1Tarr:Array = ['Tank(1)','Tank(1)','Tank(2)','Tank(1)','Tank(2)','Tank(3)','Tank(1)','Tank(2)','Tank(3)'];

    if(tanktimer == lv1arr[we])
	{
		trace('work darn you!');
		n = new lv1Tarr[we];
		n.x = 700;
		n.y = 550;
		addChild(n);
		trace('build');
		we++;
	}


the var 'we' is defined at the top as an Number=0 as is tanktimer.

What i think should be happening is that tanktimer counts up from 0 to 24 and then it will be equal to the first value in lv1arr at which point it will build the first item in lv1Tarr.

I'm pretty sure the problem is:

    n = new lv1Tarr[we];

as the code gets to there then gives the error and generates no tank.  But if I remove lv1Tarr[we] and replace it with Tank(1) it works just fine so clearly flash doesn't want me using an array in this manner.  Help?