any blackhawk experts, or crew members out there?

The wires below the seats and the seat struts work together to keep the stroke as vertical as possible.

thanks,  all we had to go by so far was a spec that basically says the same thing about nothing below the seat.  It's difficult playing in some other company's sand box........

Are you asking how does the seat stroke? The seats stroke straight down. There is a wire in each of the vertical seat tubes that is shaped like a clover leaf at the top. Two rollers per side are inside the side loops of the clover leaf with bolts through the them and the tube. The upper attachment hook is connected to the top loop. When the seat strokes, the rollers pull through the remaining 2 feet or so of coat hanger thick wire. The troop and gunner seats can absorb the energy of a 10G impact. Do not store anything beneath the seats in a 'hawk or it will be implanted up your backside in a crash!

Hope this helps.