Narrative:

After a normal landing and deceleration on runway xxr at ZZZ I applied normal braking and below 80 kts applied nosewheel steering both of which operated normally. Tower advise us to make a left turn on taxiway xx; back taxi runway xxl and take taxiway xy to the ramp. (Note: all taxiways and runways were dry and free of contamination at the time) turning onto taxiway xy required an approximate 120 turn to the left to join. At this point the nose wheel steering was operating normally. After the turn the aircraft started drifting to the left; I tried correcting this with opposite nose wheel steering with no effect. I immediately tried to apply maximum braking to stop all aircraft movement with no braking action resulting; by the time I was going to apply number 2 braking we were in the grass and stopped. We shut down the engines and we called the tower to advise them of our situation on taxiway xx. The tower acknowledged our call and advised us someone from [company] would be coming to assist us. I exited the aircraft to check for any damage to the aircraft and any airport infrastructure; lights; signage; etc. And there was none. I called the chief pilot to inform him of the incident. The [company] representative arranged for a tug and tow bar to assist us. The temperatures had been in the twenties so the ground was firm and the plane was returned without incident [company] coordinated the tow with the tower for towing clearances and the plane was towed to the ramp without any incident. Maintenance was called by the company and secured the aircraft.

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Original NASA ASRS Text

Title: Falcon 20 Captain reported a problem with their nose wheel steering and ended up going off the taxiway into the grass.

Narrative: After a normal landing and deceleration on Runway XXR at ZZZ I applied normal braking and below 80 kts applied nosewheel steering both of which operated normally. Tower advise us to make a left turn on Taxiway XX; back taxi Runway XXL and take Taxiway XY to the ramp. (Note: All Taxiways and Runways were dry and free of contamination at the time) Turning onto Taxiway XY required an approximate 120 turn to the left to join. At this point the nose wheel steering was operating normally. After the turn the aircraft started drifting to the left; I tried correcting this with opposite nose wheel steering with no effect. I immediately tried to apply maximum braking to stop all aircraft movement with no braking action resulting; by the time I was going to apply Number 2 braking we were in the grass and stopped. We shut down the engines and we called the Tower to advise them of our situation on Taxiway XX. The Tower acknowledged our call and advised us someone from [company] would be coming to assist us. I exited the aircraft to check for any damage to the aircraft and any airport infrastructure; lights; signage; etc. and there was none. I called the Chief Pilot to inform him of the incident. The [company] representative arranged for a Tug and tow bar to assist us. The temperatures had been in the twenties so the ground was firm and the plane was returned without incident [company] coordinated the tow with the Tower for towing clearances and the plane was towed to the ramp without any incident. Maintenance was called by the Company and secured the aircraft.

Data retrieved from NASA's ASRS site 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.