MD80 FLT CREW EXPERIENCES UNCOMMANDED ROLL FOLLOWING FAILURE OF THE FMS FMA AND THE ACCOMPANYING DISCONNECT OF THE AUTOPLT AND FLT DIRECTORS.

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THE FO WAS CLBING OUT OF FL260 FOR FL320 WITH DFGC SELECTED TO #2; WHEN BOTH FMA'S WENT BLANK ALONG WITH FLT DIRECTOR COMMAND BARS GOING OUT OF VIEW; FOLLOWED BY AN AUTOPLT AND AUTOTHROTTLE DISCONNECT. AS WE WERE LEVELING AT FL320 THE QRH WAS BEING REVIEWED AND THE ACFT WAS BEING HAND FLOWN BY THE FO. THE ACFT FLT CTLS MOMENTARILY OVER POWERED THE FO BY A L HARD OVER CTL FORCE. THE FO REGAINED CTL; FOLLOWED BY A SECOND L HARD UNCOMMANDED CTL MOVEMENT. I THEN TOOK THE CTLS IN AN ATTEMPT TO TRY TO FIGURE OUT WHAT WAS HAPPENING. WE DECLARED AN EMER; AND RETURNED TO THE ARPT LNDG 3000 LBS OVERWEIGHT WITH NO FURTHER UNCOMMANDED FLT CTL INPUTS AND AN UNEVENTFUL LNDG.SUPPLEMENTAL INFO FROM ACN 740386: WE WERE UNABLE TO CONNECT THE AUTOPLT USING EITHER DFGC. WE CONTINUED THE CLB WITHOUT AUTOFLT. AT THIS POINT I WAS HAND FLYING USING RAW DATA. AFTER LEVELING OFF AT FL320; THE ACFT MADE A BRIEF; BUT PRONOUNCED; UNCOMMANDED YAW/ROLL TO THE LEFT. I REGAINED CTL USING OPPOSITE AILERON.CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE CAPT; WHO WAS THE PNF DURING BOTH INSTANCES OF THE UNCOMMANDED L ROLL WAS UNCERTAIN WHETHER THE ROLL WAS THE RESULT OF RUDDER OR AILERON DEFLECTION. HE WAS ALSO UNABLE TO DESCRIBE THE FORCE REQUIRED TO CORRECT IT. HE DID STATE THE FO; A SMALLER INDIVIDUAL; APPEARED TO BE EXERTING A SIGNIFICANT AMOUNT OF EFFORT WHICH CAUSED HIM TO ASSUME CTL. THE ROLL DID NOT RECUR WHILE HE WAS AT THE CTLS. A MAINT BYTE CHK PRODUCED 47 ERROR CODES; THE NATURE OF WHICH THE RPTR WAS UNCLEAR. MAINT WANTED TO REPLACE A 'BLACK BOX' AND RE-DISPATCH THE ACFT. THE RPTR REFUSED STATING THE PROB APPEARED FLT CTL RELATED AND; IN HIS OPINION; WOULD REQUIRE A FLT TEST BEFORE BEING RELEASED FOR REVENUE FLT. HE MADE A LOG ENTRY TO THAT EFFECT; EFFECTIVELY GROUNDING THE ACFT. RPTR WAS UNAWARE OF THE OUTCOME OF ANY SUBSEQUENT MAINT ACTION.