...An eyewitness to the crash told The Montana Standard the plane was doing steep angle turns and then went into a nose dive.
I'm wondering if maybe this indicates that the plane was indeed overloaded as well. Gentle turns get hard to keep gentle when your ship is overweight.
Of course it could go back to that whole "6 more passengers than the plane was rated for" problem, too. Here's a minimum of 6 kids out of seatbelts as the plane makes an approach on an airport surrounded by mountains. Assume maybe 100 pounds per kid as a nice round figure, 600 pounds thrown around a cabin everytime the plane banks into a turn could take a CG and throw it to hell and gone, I'd imagine. That's 20% of the plane's rated payload moving under the influence of gravity on every turn.
Either way, this pilot gives the rest of us good ones a black eye. Given this Congress and it's proclivity to regulate the hell out of anything in response to a perceived "failure of excess liberty", I can't imagine anything good coming out of this for the rest of us in general aviation.