Narrative:

First officer landed aircraft in shifty right crosswind. Landing was made on centerline and rollout normal until end of rollout (about 15-20 mph) when aircraft began veering towards right side of runway. First officer complained she was unable to control it and I jumped on the brakes, but they were weak and we were already exiting the runway to right into dirt and thin snow (no ice on runway, however). I took control of aircraft and engaged power steering, added power to keep plane from coming to a stop and brought it back up onto the runway. On taxi back, brakes worked normally and propeller system were run up and chkjed. Low pitch stop, overspd, low and high idle N1's checked for asymmetry, etc. Everything checked out normal. Contributing factors were a right crosswind and an aircraft which has a tendency to pull a little right in beta and reverse mode (she only used beta) but neither of these should have been uncontrollable. First officer reported full left rudder and braking, but on the light transport, free castor system full left pedal deflection makes it difficult to get full brake application -- it's a stretch -- which is a technique problem. Also, the left brake may have become hot and mushy from use to counter the right crosswind effects during the rollout. Fortunately, no damage occurred and no injuries to passenger. Several things could have been done by PF: condition levers were high idle -- they could have been brought to low idle to minimize asymmetrical pulling in beta mode. If moving power levers to beta instigated veering movement, then they should have been pulled back to idle. A brake may have overheated, which can be avoided by a healthy use of reverse thrust upon touchdown, while speed is high enough still that veering movements can be countered aerodynamically with rudder deflection. Last, but not least, if brake becomes mushy and aircraft is veering, in the light transport you can engage power steering and turn it back with the nosewheel.

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Original NASA ASRS Text

Title: DURING LNDG ROLL COMMUTER LTT HAS LOSS OF ACFT CTL, EXITS RWY.

Narrative: FO LANDED ACFT IN SHIFTY R XWIND. LNDG WAS MADE ON CTRLINE AND ROLLOUT NORMAL UNTIL END OF ROLLOUT (ABOUT 15-20 MPH) WHEN ACFT BEGAN VEERING TOWARDS R SIDE OF RWY. FO COMPLAINED SHE WAS UNABLE TO CTL IT AND I JUMPED ON THE BRAKES, BUT THEY WERE WEAK AND WE WERE ALREADY EXITING THE RWY TO R INTO DIRT AND THIN SNOW (NO ICE ON RWY, HOWEVER). I TOOK CTL OF ACFT AND ENGAGED PWR STEERING, ADDED PWR TO KEEP PLANE FROM COMING TO A STOP AND BROUGHT IT BACK UP ONTO THE RWY. ON TAXI BACK, BRAKES WORKED NORMALLY AND PROP SYS WERE RUN UP AND CHKJED. LOW PITCH STOP, OVERSPD, LOW AND HIGH IDLE N1'S CHKED FOR ASYMMETRY, ETC. EVERYTHING CHKED OUT NORMAL. CONTRIBUTING FACTORS WERE A R XWIND AND AN ACFT WHICH HAS A TENDENCY TO PULL A LITTLE R IN BETA AND REVERSE MODE (SHE ONLY USED BETA) BUT NEITHER OF THESE SHOULD HAVE BEEN UNCTLABLE. FO RPTED FULL L RUDDER AND BRAKING, BUT ON THE LTT, FREE CASTOR SYS FULL L PEDAL DEFLECTION MAKES IT DIFFICULT TO GET FULL BRAKE APPLICATION -- IT'S A STRETCH -- WHICH IS A TECHNIQUE PROB. ALSO, THE L BRAKE MAY HAVE BECOME HOT AND MUSHY FROM USE TO COUNTER THE R XWIND EFFECTS DURING THE ROLLOUT. FORTUNATELY, NO DAMAGE OCCURRED AND NO INJURIES TO PAX. SEVERAL THINGS COULD HAVE BEEN DONE BY PF: CONDITION LEVERS WERE HIGH IDLE -- THEY COULD HAVE BEEN BROUGHT TO LOW IDLE TO MINIMIZE ASYMMETRICAL PULLING IN BETA MODE. IF MOVING PWR LEVERS TO BETA INSTIGATED VEERING MOVEMENT, THEN THEY SHOULD HAVE BEEN PULLED BACK TO IDLE. A BRAKE MAY HAVE OVERHEATED, WHICH CAN BE AVOIDED BY A HEALTHY USE OF REVERSE THRUST UPON TOUCHDOWN, WHILE SPD IS HIGH ENOUGH STILL THAT VEERING MOVEMENTS CAN BE COUNTERED AERODYNAMICALLY WITH RUDDER DEFLECTION. LAST, BUT NOT LEAST, IF BRAKE BECOMES MUSHY AND ACFT IS VEERING, IN THE LTT YOU CAN ENGAGE PWR STEERING AND TURN IT BACK WITH THE NOSEWHEEL.

Data retrieved from NASA's ASRS site as of July 2007 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.