Smoke in cockpit in a night operation. Return land.

Attributes
ACN	268609
Time
Date	199404
Day	Fri
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : aex
State Reference	LA
Altitude	msl bound lower : 4000 msl bound upper : 4000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	artcc : zh0
Operator	general aviation : personal
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	cruise other other other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : commercial
Experience	flight time last 90 days : 100 flight time total : 900 flight time type : 250
ASRS Report	268609
Person 2
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa
Resolutory Action	controller : provided flight assist flight crew : declared emergency other
Consequence	Other
Supplementary
Primary Problem	Aircraft

Narrative:

After leveling off at 4000 ft en route to btr, I noticed a strong burning smell. I closed the air vents and then noticed a lot of smoke coming from the dashboard. I then notified ZHU of the problem and requested a heading back to aex. The controller gave a heading and asked me if I needed any assistance. I said I would like to have anything they had since I did not know how bad the problem was. I then shut the electrical system off and this immediately solved the problem. Turned the master switch back on to lower landing gear and landed without any other problems. Callback conversation with reporter revealed the following information: the reporter had been fling an aircraft that was used the day before on a pipeline inspection flight and the pilot that had used it replaced one of the bulbs in the instrument panel which had burned out. That action was noted in the log book so might be considered aircraft maintenance action outside of the legal viewpoint, since the pilot was not an aircraft mechanic. In doing so, he placed an oversized bulb in the socket which touched the plastic housing on the instrument casing and, as our friend the reporter took off on his night journey, the bulb started to burn the cover, producing all of the smoke as reported. Being dark, the reporter could not see where the smoke came from and therefore just shut off the electrical power.

Original NASA ASRS Text

Title: SMOKE IN COCKPIT IN A NIGHT OP. RETURN LAND.

Narrative: AFTER LEVELING OFF AT 4000 FT ENRTE TO BTR, I NOTICED A STRONG BURNING SMELL. I CLOSED THE AIR VENTS AND THEN NOTICED A LOT OF SMOKE COMING FROM THE DASHBOARD. I THEN NOTIFIED ZHU OF THE PROB AND REQUESTED A HDG BACK TO AEX. THE CTLR GAVE A HDG AND ASKED ME IF I NEEDED ANY ASSISTANCE. I SAID I WOULD LIKE TO HAVE ANYTHING THEY HAD SINCE I DID NOT KNOW HOW BAD THE PROB WAS. I THEN SHUT THE ELECTRICAL SYS OFF AND THIS IMMEDIATELY SOLVED THE PROB. TURNED THE MASTER SWITCH BACK ON TO LOWER LNDG GEAR AND LANDED WITHOUT ANY OTHER PROBS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR HAD BEEN FLING AN ACFT THAT WAS USED THE DAY BEFORE ON A PIPELINE INSPECTION FLT AND THE PLT THAT HAD USED IT REPLACED ONE OF THE BULBS IN THE INST PANEL WHICH HAD BURNED OUT. THAT ACTION WAS NOTED IN THE LOG BOOK SO MIGHT BE CONSIDERED ACFT MAINT ACTION OUTSIDE OF THE LEGAL VIEWPOINT, SINCE THE PLT WAS NOT AN ACFT MECH. IN DOING SO, HE PLACED AN OVERSIZED BULB IN THE SOCKET WHICH TOUCHED THE PLASTIC HOUSING ON THE INST CASING AND, AS OUR FRIEND THE RPTR TOOK OFF ON HIS NIGHT JOURNEY, THE BULB STARTED TO BURN THE COVER, PRODUCING ALL OF THE SMOKE AS RPTED. BEING DARK, THE RPTR COULD NOT SEE WHERE THE SMOKE CAME FROM AND THEREFORE JUST SHUT OFF THE ELECTRICAL 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.