What was found
SFO-PSP - EN ROUTE, DURING TRANSITION FROM FL 250 TO FL 270, ELECTRIC ELEVATOR TRIM REPORTED STUCK IN NOSE UP POSITION. CREW UNABLE TO ADJUST ELEVATOR TRIM ELECTRICALLY OR MANUALLY. LEVEL FLIGHT ATTITUDE MAINTAINED BY ADDITIONAL APPLICATION OF FWD PRESSURE ON CONTROL YOKE. ACFT CONTINUED TO STA. ELEVATOR TRIM BEGAN TO OPERATE NORMALLY UPON DESCENT AS ACFT PASSED THROUGH 16,00 FEET. ACFT LANDED WITHOUT INCIDENT. MAINTENANCE INSPECTED ELEVATOR TRIM SYSTEM. NO DEFECTS NOTED. LUBED ELEVTOR TRIM TAB ACTUATORS. UNABLE TO DUPLICATE DISCREPANCY ON GROUND. ELEVATOR TRIM SYSTEM OPERATIONAL CHECK NORMAL. ACFT RETURNED TO SERVICE. (W)