A TECHNICIAN WHO REPLACED AN MD83 STABILIZER TRIM JACKSCREW ASSEMBLY OFFERS SEVERAL SAFETY SUGGESTIONS PERTAINING TO STABILIZER TRIM COMPONENTS.

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I HAVE A THOUGHT OR TWO THAT MAY HELP TO PREVENT FUTURE PROBS ON THE DC9/MD80 SERIES ACFT'S HORIZ STABILIZER JACKSCREWS. AT THE FACILITY WHERE I AM A CONTRACTOR A&P MECH; A 'C' CHK WAS BEING PERFORMED ON AN MD83. WE REPLACED A HORIZ STABILIZER JACKSCREW ASSEMBLY AND PERFORMED A RIG OF POS INDICATION SYS. NOT LONG AFTER THIS; THE AIRLINER ACCIDENT OCCURRED OFF OF THE CALIFORNIA COAST. THERE ARE 3 SETS OF CIRCUIT BREAKERS PROTECTING THE HORIZ STABILIZER PRIMARY/ALTERNATE DRIVE MOTORS AND AN OVERRIDE SWITCH; GUARDED ON THE L-HAND AFT AREA OF PEDESTAL IN COCKPIT. WHEN THE CREW OF AIRLINER WAS AT FL320 THE SECONDARY DRIVE MOTOR WAS RECEIVING ITS COMMANDS FROM THE AUTOPLT; AND WAS IN CHARGE. THERE HAVE BEEN SOME DC9/MD80 SERIES ACFT THAT HAVE BEEN MODIFIED TO HAVE HEATED DRIVE MOTORS. I HAVE BEEN INVOLVED WITH THE JACKSCREW AIRWORTHINESS DIRECTIVE FOR INSPECTION AND; ALTHOUGH THIS WILL ENHANCE SAFETY A BIT; THE REAL CAUSE OF THE PROB SEEMS TO BE SIDE-STEPPED. ELECTRONIC ANOMALY; NOT MECHANICAL FAILURE WAS; I SUSPECT; THE TRUE CAUSE OF THE RECENT TRAGEDY. MODIFYING ALL PRIMARY/ALTERNATE DRIVE MOTORS WITH HEATING ELEMENT; TOGETHER WITH REPLACEMENT OF ALL CIRCUIT BREAKERS PROTECTING THIS SYS; AND A TEST OF THE PRIMARY MOTOR'S INTERNAL FUSE PROTECTION ON A RECURRING BASIS ALONG WITH THE PRESENT INSPECTION/CHKS ON THE JACKSCREW ASSEMBLY ON THE DC9/MD80 ACFT. A RECURRING DETAILED INSPECTION OF THE SWITCHES LOCATED IN THE R-HAND SIDE OF THE FORWARD SIDE OF THE FORWARD CARGO PIT. THESE SWITCHES ARE FOR HORIZ STABILIZER POS INDICATOR AND AUTOPLT PITCH SERVO. ANY WEAR OF STOPS; WORN SWITCHES IN THIS AREA CAN EVOLVE INTO A CATASTROPHE IF UNCHKED OR UNATTENDED TO.