It's a site about how Top Thrill works if anybody didn't know.
I think the link might be wrong?
I tried copying and pasting it, but that didn't work.
Just go to www.machinedesign.com and go to the seach option on the top right and type in Top Thrill Dargster. it will take you to a page where you can choose between the one being discussed, (Top one) or one about TTD's down time, (1 below the top one)