[gordner]

what if you were to use the Al tubes to sleeve a (obviously as light as possible) steel spring to assist with the damping force? The inserted spring would both dampen the collision force and prevent the buckling from collapsing the Al tube inwards, forcing it to buckle outwards which may assist in keeping the forces in line...
I understood that the damping force in the front bumper shocks was largely due to them being fluid filled, and the metered release of the damping fluid after collision provided the damping much more than the buckle zones on the shocks. I know due to a rear end collision that I suffered in my 76 911S that this is how the rear shocks are intended to work, in my case they were not fluid filled (leaked out over time I am told) and thus the full force was transmitted to my tub after the shock tube distorted to its limit.