AN MD80 CAPT RPTED ON THE MOMENTARY LOSS OF CTL DURING THE FO'S ROLLOUT AFTER LNDG AT CID.

Narrative

CONDITIONS AT CID WERE MODERATE TO HVY RAIN; 2 1/2 MI VISIBILITY; 500 FT BROKEN; 1000 FT OVCST; AND WIND 090 DEGS AT ABOUT 10 KTS. FO'S LEG. WE WERE RADAR VECTORED TO INTERCEPT THE ILS TO RWY 9 BY ZAU. THE CTLR GAVE US A VECTOR TO INTERCEPT THAT LEFT US AT 3000 FT OVER THE OM; WELL ABOVE GLIDE PATH. WE ABANDONED THE APCH AND ASKED FOR VECTORS TO ANOTHER APCH. AFTER CIRCLING BACK; WE INTERCEPTED THE LOC ABOUT 5 MI OUTSIDE THE MARKER AND PROCEEDED DOWN THE GS. NORMAL APCH; ON LOC; AND GLIDE PATH ON SPD. AT 500 FT BUG PLUS 10; SINK 700 FT. ADJUSTED THE RWY LIGHTS TO MEDIUM. AT 100 FT IN SLOT AND ON SPD. AT ABOUT 50 FT DRIFTED SLIGHTLY L OF COURSE AND DSCNT RATE DECREASED TO ABOUT 300 FPM. I MADE THE COMMENT TO THE FO TO KEEP IT COMING DOWN. HE CORRECTED AND DRIFTED SLIGHTLY TO THE R OF CTRLINE. WE TOUCHED DOWN SLIGHTLY R OF CTRLINE. THE ACFT CONTINUED TO TRACK TO THE R. THE NOSE STARTED COMING TO THE L AND THE REAR OF THE ACFT CONTINUED TO THE R. AT THIS POINT WE WERE APCHING THE R SIDE OF THE RWY. I SAID TO THE FO 'R RUDDER' TO STRAIGHTEN THE ACFT AND MYSELF APPLIED R RUDDER. I IMMEDIATELY SAID 'I GOT IT' AND TOOK CTL OF THE ACFT. THE ACFT RETURNED TO A STRAIGHT TRACK AND WE RETURNED TO THE CTR OF THE RWY. I DO KNOW THAT THE FO WAS MAKING CORRECTIONS TO BRING THE ACFT BACK TO THE CTRLINE WITH NO EFFECT. WE SLOWED THE ACFT ON THE RWY; RETRACTED SPOILER AND FLAPS AND SLATS AND PROCEEDED TO THE GATE. ALL SYS NORMAL. AFTER PARKING AT THE GATE; THE GND CREW INFORMED US THAT THERE WAS GRASS AND MUD ON THE R GEAR ASSEMBLY. UP TO THAT POINT; WE DID NOT REALIZE THAT WE HAD LEFT THE HARD SURFACE. WE BELIEVE THAT THE ACFT HYDROPLANED AFTER TOUCHDOWN. THE ACFT DID NOT RESPOND TO ANY INPUTS TO RETURN TO THE CTRLINE AND WOULD HAVE CONTINUED TO ROTATE COUNTERCLOCKWISE. NOT UNTIL WE STOPPED THE ROTATION COULD WE REGAIN DIRECTIONAL CTL. AT THAT POINT; THE MAIN GEAR HAD LEFT THE RWY. THE NOSEWHEELS REMAINED ON THE RWY THROUGHOUT THE LNDG. WE BELIEVE THAT A FIRMER TOUCHDOWN MAY HAVE HELPED TO REDUCE THE HYDROPLANING AND POSSIBLY PREVENTED THE LOS OF CTL.