EA50 instructor reports rudder trim stuck in the full left position during training.

Attributes
ACN	781801
Time
Date	200804
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	msl single value : 6500
Environment
Flight Conditions	VMC
Light	Dusk
Aircraft 1
Controlling Facilities	tracon : zzz.tracon tower : elp.tower
Operator	general aviation : instructional
Make Model Name	Eclipse 500
Operating Under FAR Part	Part 91
Flight Phase	cruise : level
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	other
Function	instruction : instructor oversight : pic
Qualification	pilot : cfi pilot : multi engine pilot : atp
Experience	flight time last 90 days : 180 flight time total : 23000 flight time type : 400
ASRS Report	781801
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	other flight crewa
Resolutory Action	flight crew : landed in emergency condition flight crew : diverted to another airport
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

Simulated single engine climb for airwork when student trimmed the rudder for the failed engine; this is when the rudder trim 'froze' in the full left position. Alternate was used to be available. A check at the rudder freedom was done and yielded only a couple of degrees of motion to the right. We therefore decided to divert to the nearest airfield in which the crosswind would be from the right of the nose. We diverted to ZZZ and landed. Winds were from the right 290 degrees/15 KTS. The landing was uneventful. Callback conversation with reporter revealed the following information: the landing was completely uneventful and the aircraft was taxied to the ramp. Since the EA50 rudder trim is interfaced through the central aircraft computer it was decided to completely power down the aircraft and allow the computer to reboot. This had the desired effect and the rudder trim functioned normally afterward. The exact problem with the central aircraft computer that caused this incident is unknown.

Original NASA ASRS Text

Title: EA50 INSTRUCTOR REPORTS RUDDER TRIM STUCK IN THE FULL LEFT POSITION DURING TRAINING.

Narrative: SIMULATED SINGLE ENG CLB FOR AIRWORK WHEN STUDENT TRIMMED THE RUDDER FOR THE FAILED ENG; THIS IS WHEN THE RUDDER TRIM 'FROZE' IN THE FULL L POS. ALTERNATE WAS USED TO BE AVAILABLE. A CHK AT THE RUDDER FREEDOM WAS DONE AND YIELDED ONLY A COUPLE OF DEGS OF MOTION TO THE R. WE THEREFORE DECIDED TO DIVERT TO THE NEAREST AIRFIELD IN WHICH THE XWIND WOULD BE FROM THE R OF THE NOSE. WE DIVERTED TO ZZZ AND LANDED. WINDS WERE FROM THE R 290 DEGS/15 KTS. THE LNDG WAS UNEVENTFUL. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE LANDING WAS COMPLETELY UNEVENTFUL AND THE ACFT WAS TAXIED TO THE RAMP. SINCE THE EA50 RUDDER TRIM IS INTERFACED THROUGH THE CENTRAL ACFT COMPUTER IT WAS DECIDED TO COMPLETELY POWER DOWN THE ACFT AND ALLOW THE COMPUTER TO REBOOT. THIS HAD THE DESIRED EFFECT AND THE RUDDER TRIM FUNCTIONED NORMALLY AFTERWARD. THE EXACT PROBLEM WITH THE CENTRAL ACFT COMPUTER THAT CAUSED THIS INCIDENT IS UNKNOWN.

Data retrieved from NASA's ASRS site as of May 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.