I'm having the same issue, rluvsk06.  When I first start FSX, and I select ANY plane, other than the B-52, for Free Flight, they all start with their engines on and ready to go.  When I select the B-52, the engines are off and I can NOT get the d*** things going.  I've used every step that has been supplied in this forum.  Then when I go back and select another aircraft, even the same one I selected prior to the B-52, they're engines are spooling down, and require a start.  
Somehow the B-52 is causing all the other AC to start with their engines off, once the B-52 has been select to fly in Free Flight.