Light twin pilot was unable to unfeather #1 engine after total electrical failure.

Attributes
ACN	552057
Time
Date	200206
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : bjc.airport
State Reference	CO
Environment
Light	Daylight
Aircraft 1
Controlling Facilities	tower : bjc.tower
Operator	general aviation : personal
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Fixed Gear
Operating Under FAR Part	Part 91
Flight Phase	cruise : level
Flight Plan	None
Person 1
Affiliation	other
Function	flight crew : single pilot
Qualification	pilot : cfi pilot : multi engine pilot : instrument pilot : commercial
Experience	flight time last 90 days : 200 flight time total : 1100 flight time type : 350
ASRS Report	552057
Person 2
Affiliation	other
Function	observation : passenger
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa other flight crewb
Resolutory Action	controller : provided flight assist flight crew : landed in emergency condition other
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

I was showing the aircraft to the new owner. An extensive pre-buy had just been completed, revealing no problems. We took the left engine to full feather as a demonstration of single engine performance. While attempting to restart the left engine, the master electrical solenoid failed (mechanic told me after he inspected the plane) resulting in a total electrical failure. After running all checklists to no avail, we returned to bjc for landing. We observed the traffic pattern, entered on downwind midfield and were given a solid green light on final. When I lowered the landing gear, it shook the solenoid enough to restore our electric power. We landed with the left engine fully feathered without further incident. The cause of the problem was the failure of the master solenoid while attempting to restart the left engine in-flight. Unfortunately, the left engine could not be restarted without power.

Original NASA ASRS Text

Title: LIGHT TWIN PLT WAS UNABLE TO UNFEATHER #1 ENG AFTER TOTAL ELECTRICAL FAILURE.

Narrative: I WAS SHOWING THE ACFT TO THE NEW OWNER. AN EXTENSIVE PRE-BUY HAD JUST BEEN COMPLETED, REVEALING NO PROBS. WE TOOK THE L ENG TO FULL FEATHER AS A DEMONSTRATION OF SINGLE ENG PERFORMANCE. WHILE ATTEMPTING TO RESTART THE L ENG, THE MASTER ELECTRICAL SOLENOID FAILED (MECH TOLD ME AFTER HE INSPECTED THE PLANE) RESULTING IN A TOTAL ELECTRICAL FAILURE. AFTER RUNNING ALL CHKLISTS TO NO AVAIL, WE RETURNED TO BJC FOR LNDG. WE OBSERVED THE TFC PATTERN, ENTERED ON DOWNWIND MIDFIELD AND WERE GIVEN A SOLID GREEN LIGHT ON FINAL. WHEN I LOWERED THE LNDG GEAR, IT SHOOK THE SOLENOID ENOUGH TO RESTORE OUR ELECTRIC PWR. WE LANDED WITH THE L ENG FULLY FEATHERED WITHOUT FURTHER INCIDENT. THE CAUSE OF THE PROB WAS THE FAILURE OF THE MASTER SOLENOID WHILE ATTEMPTING TO RESTART THE L ENG INFLT. UNFORTUNATELY, THE L ENG COULD NOT BE RESTARTED WITHOUT PWR.

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.