Hi Larry

As you probably know I also have the Hell Raiser biplane. And as you know from the aerobatics forum, I've got mine pretty well trimmed out for knife edge. My HR doesn't want to roll out of the knife edge unless I enter the knife edge from a nose high (high alpha) start. But if I'm flying with a mostly level attitude before rolling into KE, the plane doesn't seem to want to roll out. I have no clue what the aerodynamic reason for this is. It might even be more of a speed issue than an AOA issue. Hard to tell. But I have seen this behavior and it seems to be avoidable if you enter the KE in certain ways.

Clark