An LR23 taxiing after landing at lex, ky, loses its ability to steer.

Attributes
ACN	413568
Time
Date	199809
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : lex
State Reference	KY
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : lex
Operator	common carrier : air taxi
Make Model Name	Learjet 23
Operating Under FAR Part	Part 135
Flight Phase	ground other : taxi
Flight Plan	IFR
Person 1
Affiliation	company : air taxi
Function	flight crew : first officer
Qualification	pilot : instrument pilot : atp pilot : cfi pilot : commercial
Experience	flight time last 90 days : 100 flight time total : 4500 flight time type : 1500
ASRS Report	413568
Person 2
Affiliation	company : air taxi
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	none taken : unable
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

After aircraft landed and taxied clear of runway, nosewheel steering was unresponsive and differential power and braking did not help steer aircraft. Crew shut down aircraft and asked for a tug. While shut down, the crew turned the aircraft and reset the steering system. We restarted and tried to taxi when it failed again and we were then tugged in to the FBO. The problem turned out to be a stuck microswitch on the main gear that was not making good contact to enable the nosewheel steering system to steer.

Original NASA ASRS Text

Title: AN LR23 TAXIING AFTER LNDG AT LEX, KY, LOSES ITS ABILITY TO STEER.

Narrative: AFTER ACFT LANDED AND TAXIED CLR OF RWY, NOSEWHEEL STEERING WAS UNRESPONSIVE AND DIFFERENTIAL PWR AND BRAKING DID NOT HELP STEER ACFT. CREW SHUT DOWN ACFT AND ASKED FOR A TUG. WHILE SHUT DOWN, THE CREW TURNED THE ACFT AND RESET THE STEERING SYS. WE RESTARTED AND TRIED TO TAXI WHEN IT FAILED AGAIN AND WE WERE THEN TUGGED IN TO THE FBO. THE PROB TURNED OUT TO BE A STUCK MICROSWITCH ON THE MAIN GEAR THAT WAS NOT MAKING GOOD CONTACT TO ENABLE THE NOSEWHEEL STEERING SYS TO STEER.

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.