Local buzz all seems to suggest both engines functioning...took off but didnt climb..then tanked in going flat out....which all seems consistent with the massive destruction.
If that is correct then clearly a control or instrument issue...
A blocked pitot static as someone has suggested could have been all it took to cause sufficient distraction and disorientation.
On a separate issue...just wonder what sort of death in service the poor families of the unfortunate pilots will get?...anyone know what the going GA rate is....? Between half a million and a million I hope....thread creep I know but highly relevant.