Plane Controller


I want my plane to make a kamikaze mission but when I simulate my scenario the pitch angle became lower than I expected. I wonder the reason behind it. I know arduplane uses a TECS controller. Is this system suitable for fighter UAVs, is there anything that can be done with the default arduplane system or does it require modification (like a new nonlinear model)? Because if arduplane system can only tolerate low angles, I need to find another way.

If someone can clarify this issue I would appreciate it. Thank you in advance.