DLC...Direct Lift Control, using wing spoiler panels to achieve accurate pitch attitude and descent rate, on the glidepath.
In addition, the shuttle has a rather steep descent path...can't remember offhand just how steep, but steep.
12 degrees rings a bell.
And as for automatic approach landings (oftentimes call 'autolands')...it's safer, and generally more accurate as well.
Last edited by 411A; 25th Apr 2006 at 21:50.