DC10-40 EXPERIENCES A STALL WARNING AT 3000 FT WITH A SUBSEQUENT AUTO SLAT DEPLOYMENT IN RESPONSE. CLT CREW USE OF THEIR CHKLISTS AND CONFERENCE CALL WITH ACR MAINT FAILED TO RESOLVE THEIR PROB. FUEL DUMPED AND ACFT RETURNED TO SFO. ACI ON BOARD SAID; 'GOOD JOB; BUT RPT TO ASRS.' PROB WAS A STUCK L WING STALL SENSOR.

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DOMESTIC FLT ON A DC10-40 FROM SFO-MSP. NORMAL TKOF FROM SFO RWY 1R. AFTER GEAR AND FLAPS RETRACTED; AIRSPD 250 KIAS; STALL WARNING/STICK SHAKER ACTIVATED. AUTOSLATS DEPLOYED TURNING ON SLAT DISAGREE AND SLAT RESET LIGHTS. AFTER TROUBLESHOOTING WITH THE PROC IN THE COMPANY OPERATING MANUAL AND CONFERRING WITH MAINT CTL; IT WAS DETERMINED THAT THE SLATS WOULD NOT RETRACT. A VISUAL CHK CONFIRMED THE AUTO SLATS INDEED HAD DEPLOYED AND REMAINED DEPLOYED AFTER RUNNING THE PROC. WITH CONCURRENCE FROM DISPATCH; DECISION WAS MADE TO RETURN TO SFO. AFTER ADVISING ATC; 10000 LBS OF FUEL WAS DUMPED TO GET DOWN TO LNDG WT. DUMP LOCATION 070 DEGS/80 NM SFO AT FL230 AT XX30Z FOR 2 MINS. AN UNEVENTFUL LNDG WAS MADE AT SFO. COMPANY MAINT AT SFO DISCOVERED THE L WING STALL SENSOR STUCK IN THE STALL SIGNAL POS. THEY SAID THE SLATS COULD NOT RETRACT BECAUSE THE SENSOR WOULD NOT RESET WITH THE COMPANY OPERATING MANUAL PROC. MAINT REPLACED THE SENSOR AND A ROUTINE FLT WAS THEN MADE SFO-MSP. THERE WAS AN FAA ACR INSPECTOR ON BOARD ADMINISTERING A CREW CHK RIDE DURING THE EVENT. HE CONTINUED ON WITH US TO MSP AFTER WE WERE FIXED IN SFO. WHEN ARRIVING IN MSP; THE INSPECTOR SAID THE CREW HANDLED THE INCIDENT WELL AND DISPLAYED GOOD CREW COORD. HE ALSO REMINDED US TO FILE AN AIR SAFETY RPT WHICH THE CAPT PROMPTLY DID WHEN WE RETURNED TO OUR DTW BASE LATER THAT SAME DAY. ACFT CTL WAS NEVER COMPROMISED THROUGHOUT THE EVENT. WE HAD THE APPROPRIATE AIRSPD AND ATTITUDE FOR OUR CLB PROFILE AND KNEW ALMOST IMMEDIATELY THAT WE WERE RECEIVING A FALSE STALL WARNING. WE WERE ABLE TO STOP THE STICK SHAKER BUT AS STATED ABOVE COULD NOT RESET THE AUTO SLAT SIGNAL. OUR COMPANY OPERATING MANUAL PROC DID NOT SPECIFICALLY ADDRESS THIS POSSIBILITY BUT AFTER TALKING TO OUR COMPANY MAINT CTL ON A PHONE PATCH WE PRETTY MUCH FIGURED IT WAS A STUCK SENSOR. THE COMPANY OPERATING MANUAL PROC DOES; HOWEVER; TELL YOU HOW TO PROCEED IN THE EVENT YOU CAN'T GET THE SLATS TO RETRACT.