What was found
CLIMBING THROUGH 13,000 FT USING F/O FLIGHT DIRECTOR IN AIRSPEED MODE AND WITH AUTOPILOT ENGAGED, AIRSPEED BUG WENT TO 40 KNOTS AND FLIGHT DIRECTOR COMMANDED PITCH UP TO CAPTURE AIRSPEED. PITCH MODE WAS SELECTED TO OBTAIN NORMAL PITCH ATTITUDE. AIRSPEED MODE WAS RESELECTED WITH NO FURTHER PROBLEM. RETURNED TO THE FIELD AND ACCOMPLISHED A UNEVENTFUL LANDING. CHECKED MDC FOR CURRENT A/P FAULTS, NO FAULTS FOUND. DOWNLOADED MDC REPORTS. DOWNLOADED DFDR DATA IAW TASK CARD R313101. PERFORMED LLM RTS TEST IAW TASK CARD R221101 FOR FCP. ACFT CONTINUED CAT III. PLACARD REMAINS CAT III. C/W TASK CARD CRJ700-SL-22-006. RETURNED TO SERVICE. COULD NOT DUPLICATE. NO COMPONENTS REPLACED.