CRJ700 FLT CREW EXPERIENCED UNCONTROLLABLE NOSE GEAR STEERING AFTER TOUCHDOWN.

Narrative

STEERING INOP. THE FIRST TIME IT HAPPENED WAS LAST WEEK LANDING ON RWY XX. NOTHING ABNORMAL ABOUT THE LANDING. AS SOON AS THE LANDING GEAR TOUCHED DOWN THE STEERING NOSE MESSAGE APPEARED. I WAS AT THE CONTROL AND USED THE MAX REVERSER FOR THE STOPPING THE ACFT; BUT AS SOON AS THE NOSE GEAR TOUCHED DOWN; THE ACFT PULLED TO THE RIGHT. AT THAT POINT WE USED THE MAX BRAKE AND LITERALLY WE WERE STANDING ON THE BRAKE; BY THEN THE ACFT CAME TO STOP JUST A COUPLE OF FEET FROM THE EDGE OF THE RWY. WE WERE DISABLED ON THE RWY. USED DIFFERENTIAL POWER TO GET THE ACFT OFF THE RWY. RAN THE QRH; CALLED MAINT AND GOT THE STEERING BACK AND MOVED TO THE GATE AND WROTE IT UP. THE SECOND TIME THIS HAPPENED WAS A WEEK LATER WITH XWIND 15 ON A DRY RUNWAY. LANDING WAS NORMAL; BUT AS SOON AS MAIN LANDING GEAR TOUCHED DOWN THE STEERING INOP DISPLAYED; SO THIS TIME USED MAX REVERSER TO SLOW THE ACFT AND STAYED ON THE CENTER LINE. BUT AS SOON AS NOSE GEAR TOUCH DOWN THE ACFT TURNED VERY VIOLENTLY TO THE LEFT AND RUDDER AND DIFFERENTIAL POWER DID NOT HELP. SO STOOD ON THE BRAKE AND ACFT CAME TO STOP JUST BY THE LEFT EDGE OF THE RWY. WE RAN THE QRH AND GOT THE STEERING BACK AND TAXIED TO THE GATE AND WROTE IT UP. ON THE 1ST INCIDENT I TALKED TO MAINT AND HE TOLD ME THAT ON THE 700 THEY HAVE TAKEN THE SNUBBERS OFF. ON THE 2ND INCIDENT THE NOSE OF THE ACFT WAS NOT CENTERED AS SOON AS THE NOSE TOUCH DOWN ACFT POINTED TO THE LEFT VERY VIOLENTLY. THIS IS A SERIOUS ISSUE; ESPECIALLY SINCE IT HAS HAPPENED TWO TIMES IN A ROW AND WITHIN THE WEEK. I AM NOT SURE IF THIS HAS HAPPENED TO ANYBODY ELSE OR HOW OFTEN IT HAPPENS TO THE OTHER CREW AND IF THEY ARE WRITING IT UP OR SIMPLY THEY GET THEIR STEERING BACK AND MOVING ON. THIS IS A SAFETY AND VERY SERIOUS ISSUE.CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE REPORTER STATED THAT THE MALFUNCTION OCCURRED ON TWO SEPARATE ACFT. IN BOTH INSTANCES; THE 'STEERING INOP' MESSAGE APPEARED WITH MAIN GEAR TOUCHDOWN. THE NOSE GEAR WAS SUBSEQUENTLY UNCONTROLLABLE THE INSTANT IT MADE CONTACT WITH THE RWY. THE FLT CREW WAS ABLE TO STOP THE ACFT BEFORE IT DEPARTED THE RWY. THEY WERE ABLE TO REGAIN CONTROL BY TURNING THE NOSEWHEEL STEERING SWITCH OFF; RECYCLING TWO CB'S; THEN TURNING THE SWITCH BACK ON. APPARENTLY THIS SWITCH ELECTRICALLY ACTIVATES THE NOSEWHEEL STEERING AND IS TURNED ON AFTER PUSHBACK AND REMAINS ON UNTIL THE FLT IS COMPLETE AND THE ACFT PARKED. THE REPORTER STATED THAT A MECHANIC MENTIONED THAT THE NOSEWHEEL SNUBBERS HAVE RECENTLY BEEN REMOVED FROM OTHER CRJ'S.