If I understand correctly the shuttle leaves orbit in a calculated window. Passed this window a full orbit has to be performed before a new entry can be made. The shuttle then enters the atmosphere at around Mach 25 over Washington state. During a continuous decellerating descent it becomes controllable with its flight controls at around Mach 7. It overflies the space shuttle landing facility at Kennedy space port at 30,000 ft and Mach 2. On downwind it becomes subsonic, hence the double sonic boom. It turn final at 10,000 ft, following a 'meat ball' type vasi, which is positioned at 1 NM final. Then it switches to a 3 degree glide angle to touch down at 200Kt. Mannually or automatically flown, using actual and predicted wind and temp. information.
SJ
[ 04 August 2001: Message edited by: Switch Jock ]