AN ACR B737 FLC HITS THE WAKE OF AN FK10 THAT CROSSED THEIR TRACK 2000 FT ABOVE AND 5 NM AHEAD OF THEM. THE B737 ROLLED TO THE L 20-30 DEGS BEFORE THE FO RECOVERED. DURING THE POST RECOVERY DISCUSSION THE FLC OVERSHOT THE AIRWAY THEY WERE SUPPOSED TO INTERCEPT. THE ARTCC CTLR CORRECTED THEM.

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ACFT EXPERIENCED UNCOMMANDED ROLL AT FL310. SHORTLY AFTER THIS EVENT ARTCC INSTRUCTED CREW TO TURN L 210 DEGS AND REINTERCEPT AIRWAY. HDG SELECT MODE SELECTED AND HDG BUG ROTATED TO 210 DEGS. HOWEVER; AS A RESULT OF CREW DISTR CAUSED BY UNCOMMANDED ROLL; LNAV MODE NOT SELECTED. ACFT FLEW 5.2 NM PAST AIRWAY CTRLINE. ATC ADVISED OF SIT AT TIME OF OCCURRENCE. FLT CONTINUED WITHOUT FURTHER INCIDENT. DIVISION OF ATTN LOST AS A RESULT OF UNCOMMANDED ROLL OF B737-400. ROLL CAUSED BY UNKNOWN REASONS. USE OF ELECTRONIC ITEMS BY PAX SHOULD BE FURTHER RESEARCHED BY NTSB. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THIS ACR B737-400 FO SAID THAT THE INITIAL INDICATION OF THE WAKE WAS A SLIGHT BUFFETING THAT CAUSED THE FLC TO RECHK THE ACFT FOR A CONFIGN PROB. THEN THE ACFT STARTED A ROLL TO THE L WHILE STILL ON AUTOPLT. THE FO; WHO WAS FLYING; DISCONNECTED THE AUTOPLT AND STARTED TO ROLL THE WINGS LEVEL AND AT THIS TIME HE SAID THAT HE SAW THE OTHER ACFT ABOVE AND IN FRONT OF THEM. HE SAID THAT INITIALLY THE FLC WAS NOT SURE THAT WAKE WAS THE CAUSE OF THE ROLL. HE SAID THAT THE ACFT RECOVERED WELL; HOWEVER; AS HE ROLLED THE ACFT HE UNLOADED IT AERODYNAMICALLY BY RELEASING BACK PRESSURE AND IT LOST 400-500 FT DURING THE ROLL TO WINGS LEVEL. ADDITIONALLY; HE NOTED THAT THE MACH HAD INCREASED FROM .74 TO .76 AS HE STARTED HIS RECOVERY; SO HE RETARDED THE THRUST LEVERS. THE RPTR SAID THAT THE CAPT AND HE EXPRESSED CONCERN; THINKING THAT IT WAS A MECHANICAL FAILURE; AS THE ACFT ROLLED. BUT; BASED ON THE ACFT PERFORMANCE DURING THE RECOVERY; THE LACK OF ANY YAW MOMENT AND THE PRESENCE OF THE OTHER ACFT IN IDEAL WAKE CONDITIONS; THE FLC CONCLUDED THAT WAKE CAUSED THE ROLL. THEIR DISCUSSION OF THE EVENT DISTR THEM AND THE FO OVERSHOT THE INTERCEPT FOR THE AIRWAY THAT THEY WERE TO JOIN. SUPPLEMENTAL INFO FROM ACN 374462: CLRNC WAS TO FLY DIRECTLY TO BIGGY; JOIN J75; CLBING TO FL310. AT FL308 AND BEFORE INTERCEPTING J75; ACFT EXPERIENCED UNCOMMANDED ROLL TO THE L; 20-30 DEGS BANK. FO WAS MONITORING THE AUTOPLT AND RECOVERED. DURING RECOVERY; ACFT DSNDED TO FL306; HDG CHANGED APPROX 20 DEGS TO L. WE CLBED BACK TO FL310 AND BEGAN TO TROUBLESHOOT EVENT. ATC CALLED TO ASK IF WE WERE TURNING YET TO INTERCEPT J75 BECAUSE WE FLEW THROUGH THE CTRLINE OF THE AIRWAY AND WE WERE NEAR A RESTR AREA. WE TURNED TO THE R AND INTERCEPTED J75. I CHKED THE DISTANCE FROM AIRWAY CTRLINE AT BEGINNING OF CORRECTION TO RETURN ON COURSE. FMC SHOWED 5.3 NM. ATC GAVE US A FREQ CHANGE; AND AFTER CHKING IN ON THE NEW SECTOR; I RETURNED TO PREVIOUS FREQ (134.32) TO ADVISE THE CTLR THAT WE HAD EXPERIENCED AN UNCOMMANDED ROLL; AND TO ASK WHAT TFC WE WERE FOLLOWING AND DISTANCE. (FOKKER; 5 MI AHEAD; BUT AFTER REVIEWING EVENT; I DON'T BELIEVE THAT WAKE TURB WAS THE CAUSE OF THE ROLL.) OTHER INFO: AT TIME OF EVENT; 'B' AUTOPLT ENGAGED BOTH FLT DIRECTORS ON (FO'S FLT DIRECTOR WAS MASTER); AUTOTHROTTLES WERE ON; VNAV ON; LNAV ON (I BELIEVE). DURING ROLL RECOVERY; FO INPUTS TO CTL WHEEL PUT AUTOPLT IN CTL WHEEL STEERING ROLL AND CTL WHEEL STEERING PITCH. AUTOPLT WAS NOT DISENGAGED; AND AUTOTHROTTLES REMAINED ENGAGED. OTHER FACTORS: TCASII ON MEL; R ELEVATOR TAB HAD BEEN REPLACED WITH NOTE IN LOGBOOK THAT ACFT WAS RESTR TO MACH .75; A DC10 FO OCCUPIED THE JUMP SEAT. A PRONOUNCED BUFFET PRECEDED AND CONTINUED DURING ROLL EVENT. NO YAW WAS NOTED. I BELIEVE THAT THE DEV FROM THE RTE WAS THE RESULT OF THE UNCOMMANDED ROLL EVENT AND THE SUBSEQUENT RECOVERY AND TROUBLESHOOTING. I DID NOT IMMEDIATELY INFORM ATC OF THE EVENT BECAUSE OF TIME TO RECOVER; TIME TO DETERMINE ACFT STATUS; CTLABILITY AND INJURIES (NONE); AND CHANGE TO ANOTHER ATC FREQ. I DECIDED TO CONTINUE FLT DEST (CLT) FOR FOLLOWING REASONS: AFTER EVENT; ACFT APPEARED NORMAL; WANTED TO PUT MORE TIME AND DISTANCE BTWN ROLL EVENT AND APCH AND LNDG; DID NOT WANT TO RETURN TO EWR BECAUSE EARLIER APCH THERE HAD BEEN BUMPY WITH 92 DEG TEMP AND WINDS 11 KTS; GUSTING TO 16 KTS.