After a few years of using TrakIR I discoverd why when you whip your head around too rapidly it locks back and up or locks you down looking at the floor. I only use the basic air combat profile provided by the TrakIR software.
If you are using the flat reflective dot that comes with the TrakIR the camera cannot track it as you turn it out or up to the end of your travel arc. The reason for this is the flat dot to the camera is seen as its full light reflection entity when you are looking dead center to the monitor. As you angle away you are reducing the size of the dots reflective surface and the camera looses it, especially when you whip your head around rapidly. If you wear glasses, reflections from the lenses confuse the camera as you turn farther away from dead center because the size of the dot's reflective surface gets smaller.
I solved the problem for myself by the following:
1. Get a peice of 1/4 inch threaded rod 2 inches long and a rounded end nut.
2. Cover the rounded end nut completely with the reflective sticky dots from TrakIR.
3. Tape this to the top of your hat brim.
Because the end nut is fully coverd with reflective material, no matter how far up, down, side to side you turn your head, the camera still sees the same size dot as when you look directly into the monitor. If you have a track hat with the metal clip on you will notice the reflective surfaces have been curved for this reason.
I have an arm taped to the top of my monitor that brings my camera to 12-14 inces of my hat brim at dead center.
P.S. I have vector enabled and the track hat with clip. I find the basic dot tracking works best for me because its probelmatic contorting your body around with vectoring enabled to see out your 6 very well. If you have dot tracking enabled then the software will default to the 6 view you saved with F10 before you installed TrakIR.