http://spaceflight.nasa.gov/realdata/groundtracs/sts-107/ksc255/DOL.html
Entry flight control is maintained with the aerojet DAP, which generates effector and RCS jet commands to control and stabilize the vehicle during its descent from orbit. The aerojet DAP is a three-axis rate command feedback control system that uses commands from guidance in automatic or from the flight crew's RHC in control stick steering. Depending on the type of command and the flight phase, these result in fire commands to the RCS or deflection commands to the aerosurfaces.
In the automatic mode, the orbiter is essentially a missile, and the flight crew monitors the instruments to verify that the vehicle is following the correct trajectory. The onboard computers execute the flight control laws (equations). If the vehicle diverges from the trajectory, the crew can take over at any time by switching to CSS. The orbiter can fly to a landing in the automatic mode (only landing gear extension and braking action on the runway are required by the flight crew). The autoland mode capability of the orbiter is used by the crew usually to a predetermined point in flying around the heading alignment cylinder. In flights to date, the crew has switched to CSS when the orbiter is subsonic. However, autoland provides information to the crew displays during the landing sequence.