Narrative:

I began the day with a ZZZ1 turn; then the ZZZ leg. The ZZZ1 turn had WX en route; but was uneventful. The ZZZ leg had WX on departure; but was good the remainder of the flight. Upon our initial descent into the ZZZ area; an advisory EICAS message; hydraulic 1 low quantity; appeared. The aom volume #1 was referenced and checklist accomplished. The hydraulic page was monitored with no changes. I then listened to the ATIS. The captain and I discussed the calm winds and that we would use runway xx and use flaps 22 degrees. At gear extension; the EICAS message extinguished. The captain flew a stabilized approach and made a smooth landing in the touchdown zone. The nosewheel smoothly touched down on the runway at which time the aircraft began drifting to the left. The captain was unable to maintain the runway centerline. After the aircraft slowed and directional control was regained; the captain exited the runway. We then contacted the tower and notified them of a possible runway light strike. We performed the after landing checklist and shut down both engines with the APU running. The captain spoke with the flight attendant and passenger to inform them of the situation and ensure no one was injured. Dispatch; maintenance; and ZZZ operations were then all contacted. We waited on the taxiway until contract maintenance could confirm it was safe to be towed in. We were towed to the gate; deplaned our passenger and performed the parking and terminating checklists. The captain made the maintenance log entry. I conducted a postflt inspection. The front tires were bald and the #2 tire was damaged and the wheel well contained FOD. We then submitted to the alcohol tests. Callback conversation with reporter revealed the following information: reporter stated that runway inspection revealed nosewheel skid marks on runway centerline; then veering to the left toward runway edge. The pilot was able to maintain centerline until rudder effectiveness was lost as speed was reduced. As the aircraft approached the runway edge; differential braking became more effective and directional control was regained. Apparently; this aircraft type exhibits an anomaly whereby the nosewheel steering initiates an uncommanded turn. A procedure for 'uncommanded swerving' is detailed in the pilot's handbook.

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Original NASA ASRS Text

Title: EMB-145 DRIFTED UNCONTROLLABLY TO THE LEFT AFTER TOUCHDOWN; STRIKING A RWY LIGHT BEFORE CONTROL WAS REGAINED.

Narrative: I BEGAN THE DAY WITH A ZZZ1 TURN; THEN THE ZZZ LEG. THE ZZZ1 TURN HAD WX ENRTE; BUT WAS UNEVENTFUL. THE ZZZ LEG HAD WX ON DEP; BUT WAS GOOD THE REMAINDER OF THE FLT. UPON OUR INITIAL DSCNT INTO THE ZZZ AREA; AN ADVISORY EICAS MESSAGE; HYD 1 LOW QUANTITY; APPEARED. THE AOM VOLUME #1 WAS REFED AND CHKLIST ACCOMPLISHED. THE HYD PAGE WAS MONITORED WITH NO CHANGES. I THEN LISTENED TO THE ATIS. THE CAPT AND I DISCUSSED THE CALM WINDS AND THAT WE WOULD USE RWY XX AND USE FLAPS 22 DEGS. AT GEAR EXTENSION; THE EICAS MESSAGE EXTINGUISHED. THE CAPT FLEW A STABILIZED APCH AND MADE A SMOOTH LNDG IN THE TOUCHDOWN ZONE. THE NOSEWHEEL SMOOTHLY TOUCHED DOWN ON THE RWY AT WHICH TIME THE ACFT BEGAN DRIFTING TO THE L. THE CAPT WAS UNABLE TO MAINTAIN THE RWY CTRLINE. AFTER THE ACFT SLOWED AND DIRECTIONAL CTL WAS REGAINED; THE CAPT EXITED THE RWY. WE THEN CONTACTED THE TWR AND NOTIFIED THEM OF A POSSIBLE RWY LIGHT STRIKE. WE PERFORMED THE AFTER LNDG CHKLIST AND SHUT DOWN BOTH ENGS WITH THE APU RUNNING. THE CAPT SPOKE WITH THE FLT ATTENDANT AND PAX TO INFORM THEM OF THE SITUATION AND ENSURE NO ONE WAS INJURED. DISPATCH; MAINT; AND ZZZ OPS WERE THEN ALL CONTACTED. WE WAITED ON THE TXWY UNTIL CONTRACT MAINT COULD CONFIRM IT WAS SAFE TO BE TOWED IN. WE WERE TOWED TO THE GATE; DEPLANED OUR PAX AND PERFORMED THE PARKING AND TERMINATING CHKLISTS. THE CAPT MADE THE MAINT LOG ENTRY. I CONDUCTED A POSTFLT INSPECTION. THE FRONT TIRES WERE BALD AND THE #2 TIRE WAS DAMAGED AND THE WHEEL WELL CONTAINED FOD. WE THEN SUBMITTED TO THE ALCOHOL TESTS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: REPORTER STATED THAT RUNWAY INSPECTION REVEALED NOSEWHEEL SKID MARKS ON RWY CENTERLINE; THEN VEERING TO THE LEFT TOWARD RWY EDGE. THE PLT WAS ABLE TO MAINTAIN CENTERLINE UNTIL RUDDER EFFECTIVENESS WAS LOST AS SPEED WAS REDUCED. AS THE ACFT APPROACHED THE RWY EDGE; DIFFERENTIAL BRAKING BECAME MORE EFFECTIVE AND DIRECTIONAL CONTROL WAS REGAINED. APPARENTLY; THIS ACFT TYPE EXHIBITS AN ANOMALY WHEREBY THE NOSEWHEEL STEERING INITIATES AN UNCOMMANDED TURN. A PROCEDURE FOR 'UNCOMMANDED SWERVING' IS DETAILED IN THE PLT'S HANDBOOK.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.