You guys make my head hurt! However, I tend to agree that "randomness" appears to be a too simple explanation when all of the (facts,processes,equations,internal and external influences) are unknown or undefined.
I am finding the current shuttle flight and it's plight interesting as the launch/reentry damages have been around since day 1 of the shuttle program, but the fact that the fuel tank insulation FINALLY caused damage in the wrong place on the shuttle, the knowledge of prior shuttle damage has finally surfaced to the public.
"This is a random event because it has never happened before ..."
Current known issues affecting the shuttle Columbia are:
Adheasion
Location
Mass
Force
Thrust
Trajectory of the projectile based upon the above 3 items plus
atmospheric conditions
shuttle launch trajectory
shuttle launch thrust
et cetera, et cetera, et cetera.
Random? No. On the Columbia it's that all the components for any given disaster came together in an order to create the explosion.
Replicable.