Those "S" shaped moves don't come until the very end of the landing process...just a minute before they actuall touchdown...180 degree turns, two of them in opposite directions with the final turn lining them up with the end of the runway...
Not that I understand this at all, but did you read
the live thread that leadpenny was running as it happenned, while watching NASA channel?
"The Columbia was making four drastic turns over the western US to dissapate speed. That's the last they heard from it. 41 posted on 02/01/2003 8:21 AM CST by leadpenny [ Post Reply | Private Reply | View Replies | Report Abuse ]"