Sa-227 captain experiences a sudden loss of nose wheel steering control during taxi out; resulting i...

Attributes
ACN	1208999
Time
Date	201410
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	SA-227 AC Metro III
Operating Under FAR Part	Part 135
Flight Phase	Taxi
Route In Use	None
Flight Plan	IFR
Component
Aircraft Component	Nosewheel Steering
Person 1
Function	Captain Pilot Flying Single Pilot
Qualification	Flight Crew Multiengine Flight Crew Instrument Flight Crew Flight Instructor Flight Crew Commercial
Experience	Flight Crew Last 90 Days 150 Flight Crew Total 1850 Flight Crew Type 450
Events
Anomaly	Aircraft Equipment Problem Critical Ground Excursion Taxiway Inflight Event / Encounter Loss Of Aircraft Control

Narrative:

While taxiing out for departure when it appeared the nose wheel steering failed and turned to the left about 30-40 percent of full travel (estimated). The aircraft was traveling at approximately 10-15 knots and the reported winds were 230 at 8 kts. The aircraft veered sharply to the left at which time I placed both engines in full reverse and used full braking in an attempt to stop. The aircraft continued forward and began to exit the taxiway into the grass at which point I pulled both engine stop and feather knobs and tried using braking to avoid runway and taxiway lights. After coming to a stop ATC notified me that airport operations was en route at which time I powered down the plane. After a thorough inspection from both myself and maintenance it was determined that no obstacles (lights; signs; etc) were struck by the prop or the landing gear. Airport operations reported no damage to airport property and the plane was then towed to the FBO and was turned over to maintenance for further inspections.

Original NASA ASRS Text

Title: SA-227 Captain experiences a sudden loss of nose wheel steering control during taxi out; resulting in a sharp swerve to the left and a taxiway excursion before the aircraft can be stopped.

Narrative: While taxiing out for departure when it appeared the nose wheel steering failed and turned to the left about 30-40 percent of full travel (estimated). The aircraft was traveling at approximately 10-15 knots and the reported winds were 230 at 8 kts. The aircraft veered sharply to the left at which time I placed both engines in full reverse and used full braking in an attempt to stop. The aircraft continued forward and began to exit the taxiway into the grass at which point I pulled both engine stop and feather knobs and tried using braking to avoid runway and taxiway lights. After coming to a stop ATC notified me that airport operations was en route at which time I powered down the plane. After a thorough inspection from both myself and Maintenance it was determined that no obstacles (lights; signs; etc) were struck by the prop or the landing gear. Airport operations reported no damage to airport property and the plane was then towed to the FBO and was turned over to Maintenance for further inspections.

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.

Sa-227 captain experiences a sudden loss of nose wheel steering control during taxi out; resulting in a sharp swerve to the left and a taxiway excursion before the aircraft can be stopped.