Electrical smoke from behind the instrument panel of a piper PA38-112 is well taken care of by the o...

Attributes
ACN	553149
Time
Date	200207
Day	Tue
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : fcm.airport
State Reference	MN
Altitude	msl single value : 3500
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Operator	general aviation : instructional
Make Model Name	PA-38 Tomahawk
Operating Under FAR Part	Part 91
Flight Phase	cruise : level
Flight Plan	None
Person 1
Affiliation	other
Function	flight crew : single pilot instruction : instructor oversight : pic
Qualification	pilot : instrument pilot : multi engine pilot : commercial pilot : cfi
Experience	flight time last 90 days : 180 flight time total : 1450 flight time type : 80
ASRS Report	553149
Person 2
Affiliation	other
Function	flight crew : single pilot instruction : trainee
Events
Anomaly	aircraft equipment problem : critical other anomaly other anomaly other
Independent Detector	other flight crewa other flight crewb
Resolutory Action	flight crew : landed in emergency condition
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

Night local flight with student pilot. Flew out to practice area for maneuvers. Completed maneuvers then began to smell possible burning insulation. Interior panel lights flickered and failed. All gauges read normal including ammeter and alternator annunciator not illuminated, no circuit breakers popped. We proceeded back to fcm. Smell began to intensify and I turned off all electrical non essential equipment. We then went through the emergency electrical fire in-flight checklist, shut off battery master/alternator and all electrical equipment. Shortly after the smoke stopped, we landed without incident and taxied back to ramp. There was heat coming from under the instrument panel. No fire was ever seen or presumed present. Possible causes could have been an overheated battery or 2 wires touching that melted some wire insulation. Throughout entire flight, all gauges read normal and the only electrical equipment lost was the panel lights. No human factors considerations. We performed everything as per the checklist and all went well. Callback conversation with reporter revealed the following information: after the fact, maintenance found a short in the navigation light wiring behind the instrument panel.

Original NASA ASRS Text

Title: ELECTRICAL SMOKE FROM BEHIND THE INST PANEL OF A PIPER PA38-112 IS WELL TAKEN CARE OF BY THE OPERATING HANDBOOK PROCS.

Narrative: NIGHT LCL FLT WITH STUDENT PLT. FLEW OUT TO PRACTICE AREA FOR MANEUVERS. COMPLETED MANEUVERS THEN BEGAN TO SMELL POSSIBLE BURNING INSULATION. INTERIOR PANEL LIGHTS FLICKERED AND FAILED. ALL GAUGES READ NORMAL INCLUDING AMMETER AND ALTERNATOR ANNUNCIATOR NOT ILLUMINATED, NO CIRCUIT BREAKERS POPPED. WE PROCEEDED BACK TO FCM. SMELL BEGAN TO INTENSIFY AND I TURNED OFF ALL ELECTRICAL NON ESSENTIAL EQUIP. WE THEN WENT THROUGH THE EMER ELECTRICAL FIRE INFLT CHKLIST, SHUT OFF BATTERY MASTER/ALTERNATOR AND ALL ELECTRICAL EQUIP. SHORTLY AFTER THE SMOKE STOPPED, WE LANDED WITHOUT INCIDENT AND TAXIED BACK TO RAMP. THERE WAS HEAT COMING FROM UNDER THE INST PANEL. NO FIRE WAS EVER SEEN OR PRESUMED PRESENT. POSSIBLE CAUSES COULD HAVE BEEN AN OVERHEATED BATTERY OR 2 WIRES TOUCHING THAT MELTED SOME WIRE INSULATION. THROUGHOUT ENTIRE FLT, ALL GAUGES READ NORMAL AND THE ONLY ELECTRICAL EQUIP LOST WAS THE PANEL LIGHTS. NO HUMAN FACTORS CONSIDERATIONS. WE PERFORMED EVERYTHING AS PER THE CHKLIST AND ALL WENT WELL. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: AFTER THE FACT, MAINT FOUND A SHORT IN THE NAV LIGHT WIRING BEHIND THE INST PANEL.

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.

Electrical smoke from behind the instrument panel of a piper PA38-112 is well taken care of by the operating handbook procedures.