AFTER LNDG ACFT DEPARTED END OF RWY; EXCESSIVE SPD; INSUFFICIENT BRAKING AND NO REVERSE THRUST.

Narrative

ACFT LNDG AND ROLLOUT PHASE NORMAL. ATC REQUESTED US TO 'TAKE IT TO THE END AND TURN LEFT; WE HAVE AN ACFT ON 3 MI FINAL.' WE THEN BROUGHT THE PWR UP ON 2 ENGS APPROX 2200 FT FROM THE END OF RWY 8L. ALL OF A SUDDEN 60 KTS SHOWED ON THE AIRSPD INDICATOR AND I CALLED OUT 60 KTS; THE CAPT SAID 'OK.' HE ALSO RESPONDED WITH THE PWR TO IDLE AND MAX BRAKING. (REVERSE THRUST WAS NOT SELECTED). THE ACFT DEPARTED THE L SIDE AND END OF RWY 8L APPROX 70 FT OFF THE END OF THE RWY. NO DAMAGE TO ACFT (RETURNED TO SERVE 6 HRS LATER). NO DAMAGE TO ARPT FACILITIES. NO INJURIES TO CREW OR DEAD HDG PAX. CONCLUSION: CAPT LATER STATED HE WAS PULLING ON THE 'LEVERS' FOR ALL HE WAS WORTH - THEN REALIZED WHEN WE STOPPED HE HAD THE THROTTLES NOT THE REVERSERS. EVEN NOW OUR EXPERIENCE WITH THIS TYPE ACFT WE STILL FEEL THE SIGHT PICTURE WE HAD APCHING THE END WAS SUFFICIENT TO STOP THE ACFT. ACFT: NO MAINT PROBS FOUND WITH PERTINENT SYS. CAUSE: POSSIBLE MISJUDGEMENT OF SPD FOR THE PREVAILING CONDITIONS OR HYDROPLANING OR BOTH. SUPPLEMENTAL INFO FROM ACN 296878: THERE WAS NO BRAKING ACTIONS NOTED ON THE ATIS OR NOTAMS. THE END OF THE RWY HAD TIRE RESIDUE FROM LNDG ACFT; COMBINED WITH RAIN FROM THE PREVIOUS HR HAD MADE THE BRAKING ACTION NIL.