Failure of new electrical gyroscope caused smoke in cockpit during runup.

Attributes
ACN	133386
Time
Date	199001
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : ggs airport : cgs
State Reference	MD
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : personal
Make Model Name	Small Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Phase	ground : preflight
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private
Experience	flight time last 90 days : 20 flight time total : 315 flight time type : 200
ASRS Report	133386
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	other other : unspecified cockpit
Resolutory Action	flight crew : overcame equipment problem flight crew : declared emergency
Consequence	Other Other
Supplementary
Primary Problem	Aircraft

Narrative:

Summary of problem: malfunction/failure of turn/slip indicator (electrical gyro). Electrical malfunction of instrument led to failure of the gyroscope, overheating of the instrument, burning and scorching of instrument and insulation. Light wisps of smoke entered cockpit from behind instrument panel. Corrective actions: master shut down, then engine shut down. Problem actually detected during performance of pretkof check. Pilot announced to unicom/CTAF on 123.0 the problem, requested lineman standby with fire extinguisher as a precaution, and taxied to the front of the operations building. I then shut down the engine and consulted the airport manager/pilot. He concurred in my assessment of the problem with the electrical gyro, and recommended that I trip the appropriate circuit breaker and/or return to cgs with master off. I restarted, did long run-up to make certain that no other electrical problems occurred (no more smoke or burning smell) then departed. I continued flight in cruise with master switch off to prevent possible cockpit fire or colateral damage to wiring and other instruments. I turned master on briefly at college park maryland, to activate radios, announce my problem (which I described as a 'smoking turn/slip indicator), clear the pattern, request fire extinguisher to be made available, and to warn traffic that I would be landing without radio communication.

Original NASA ASRS Text

Title: FAILURE OF NEW ELECTRICAL GYROSCOPE CAUSED SMOKE IN COCKPIT DURING RUNUP.

Narrative: SUMMARY OF PROBLEM: MALFUNCTION/FAILURE OF TURN/SLIP INDICATOR (ELECTRICAL GYRO). ELECTRICAL MALFUNCTION OF INSTRUMENT LED TO FAILURE OF THE GYROSCOPE, OVERHEATING OF THE INSTRUMENT, BURNING AND SCORCHING OF INSTRUMENT AND INSULATION. LIGHT WISPS OF SMOKE ENTERED COCKPIT FROM BEHIND INSTRUMENT PANEL. CORRECTIVE ACTIONS: MASTER SHUT DOWN, THEN ENGINE SHUT DOWN. PROBLEM ACTUALLY DETECTED DURING PERFORMANCE OF PRETKOF CHECK. PLT ANNOUNCED TO UNICOM/CTAF ON 123.0 THE PROBLEM, REQUESTED LINEMAN STANDBY WITH FIRE EXTINGUISHER AS A PRECAUTION, AND TAXIED TO THE FRONT OF THE OPERATIONS BUILDING. I THEN SHUT DOWN THE ENGINE AND CONSULTED THE ARPT MGR/PLT. HE CONCURRED IN MY ASSESSMENT OF THE PROBLEM WITH THE ELECTRICAL GYRO, AND RECOMMENDED THAT I TRIP THE APPROPRIATE CIRCUIT BREAKER AND/OR RETURN TO CGS WITH MASTER OFF. I RESTARTED, DID LONG RUN-UP TO MAKE CERTAIN THAT NO OTHER ELECTRICAL PROBLEMS OCCURRED (NO MORE SMOKE OR BURNING SMELL) THEN DEPARTED. I CONTINUED FLT IN CRUISE WITH MASTER SWITCH OFF TO PREVENT POSSIBLE COCKPIT FIRE OR COLATERAL DAMAGE TO WIRING AND OTHER INSTRUMENTS. I TURNED MASTER ON BRIEFLY AT COLLEGE PARK MARYLAND, TO ACTIVATE RADIOS, ANNOUNCE MY PROBLEM (WHICH I DESCRIBED AS A 'SMOKING TURN/SLIP INDICATOR), CLEAR THE PATTERN, REQUEST FIRE EXTINGUISHER TO BE MADE AVAILABLE, AND TO WARN TFC THAT I WOULD BE LNDG WITHOUT RADIO COM.

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.