Narrative:

We departed maf, on an instrument flight plan to lhk. About 10 min after takeoff, our left generator fail light came on. We were climbing to FL230 at the time. We turned the generator off to let the circuit breaker cool. We checked system per abnormal operations checklist. We also managed the electrical load for single generator operation. My co-captain and I tried resetting the circuit breaker after the proper cooling time. We were unable to get the generator back on. We were discussing how to proceed. The left engine overheat or fire warning came on. We shut down and secured the left engine. Lbb was directly in front of us. We advised ft worth center we had shut an engine down and requested to land at lbb. We were cleared straight in to runway 35. We watched for any sign of a real fire or smoke. There was none, so we did not use the fire bottle. We did not have any pass aboard nor any visual signs of a fire. When we inspected the left engine, we found the rear bearing on the starter generator had failed. This trashed our starter generator. It also caused the overheat condition warning. This starter generator had operated 350 hours since overhaul. We had noticed more carbon dust than usual on the cowling during this flight. This is not unusual when generator brushes are wearing. In this case a bearing failure was causing the brush problem. This aircraft is an xx. In the light of this failure we will watch any unusual carbon deposits more carefully. Also this starter generator worked fine until failure. It had no unusual noise or vibration.

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Original NASA ASRS Text

Title: CPR SMT EXPERIENCED GENERATOR FAILURE WITH OVERHEAT FIRE WARNING. INFLT ENGINE SHUTDOWN DIVERTED TO ALTERNATE.

Narrative: WE DEPARTED MAF, ON AN INSTRUMENT FLT PLAN TO LHK. ABOUT 10 MIN AFTER TKOF, OUR LEFT GENERATOR FAIL LIGHT CAME ON. WE WERE CLIMBING TO FL230 AT THE TIME. WE TURNED THE GENERATOR OFF TO LET THE CIRCUIT BREAKER COOL. WE CHECKED SYSTEM PER ABNORMAL OPERATIONS CHECKLIST. WE ALSO MANAGED THE ELECTRICAL LOAD FOR SINGLE GENERATOR OPERATION. MY CO-CAPT AND I TRIED RESETTING THE CIRCUIT BREAKER AFTER THE PROPER COOLING TIME. WE WERE UNABLE TO GET THE GENERATOR BACK ON. WE WERE DISCUSSING HOW TO PROCEED. THE LEFT ENGINE OVERHEAT OR FIRE WARNING CAME ON. WE SHUT DOWN AND SECURED THE LEFT ENGINE. LBB WAS DIRECTLY IN FRONT OF US. WE ADVISED FT WORTH CENTER WE HAD SHUT AN ENGINE DOWN AND REQUESTED TO LAND AT LBB. WE WERE CLRED STRAIGHT IN TO RWY 35. WE WATCHED FOR ANY SIGN OF A REAL FIRE OR SMOKE. THERE WAS NONE, SO WE DID NOT USE THE FIRE BOTTLE. WE DID NOT HAVE ANY PASS ABOARD NOR ANY VISUAL SIGNS OF A FIRE. WHEN WE INSPECTED THE LEFT ENGINE, WE FOUND THE REAR BEARING ON THE STARTER GENERATOR HAD FAILED. THIS TRASHED OUR STARTER GENERATOR. IT ALSO CAUSED THE OVERHEAT CONDITION WARNING. THIS STARTER GENERATOR HAD OPERATED 350 HRS SINCE OVERHAUL. WE HAD NOTICED MORE CARBON DUST THAN USUAL ON THE COWLING DURING THIS FLT. THIS IS NOT UNUSUAL WHEN GENERATOR BRUSHES ARE WEARING. IN THIS CASE A BEARING FAILURE WAS CAUSING THE BRUSH PROBLEM. THIS ACFT IS AN XX. IN THE LIGHT OF THIS FAILURE WE WILL WATCH ANY UNUSUAL CARBON DEPOSITS MORE CAREFULLY. ALSO THIS STARTER GENERATOR WORKED FINE UNTIL FAILURE. IT HAD NO UNUSUAL NOISE OR VIBRATION.

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