THE AIRPLANE BROKE UP IN FLIGHT WHILE DESCENDING FROM FL240. THE HORIZONTAL STABILIZER, OR TOP OF THE T-TYPE TAIL, HAD SEPARATED FROM THE FUSELAGE BEFORE GROUND IMPACT. EXAMINATION REVEALED THAT THE 47 SCREW FASTENERS THAT WOULD HAVE ATTACHED THE UPPER SURFACE OF THE LEADING EDGE ASSEMBLY FOR THE LEFT SIDE OF THE HORIZONTAL STABILIZER WERE MISSING. THEY HAD BEEN REMOVED THE NIGHT BEFORE DURING SCHEDULED MAINTENANCE. INVESTIGATION REVEALED THAT THERE WAS A LACK OF COMPLIANCE WITH THE FAA-APPROVED GENERAL MAINTENANCE MANUAL PROCEDURES BY THE MECHANICS, INSPECTORS, AND SUPERVISORS RESPONSIBLE FOR ASSURING THE AIRWORTHINESS OF THE AIRPLANE THE NIGHT BEFORE THE ACCIDENT. IN ADDITION, ROUTINE SURVEILLANCE OF THE CONTINENTAL EXPRESS MAINTENANCE DEPARTMENT BY THE FAA WAS INADEQUATE AND DID NOT DETECT DEFICIENCIES, SUCH AS THOSE THAT LED TO THIS ACCIDENT.