A B757-200 is mandated to perform a return and land when the flight crew smells an electrical burnin...

Attributes
ACN	433366
Time
Date	199903
Day	Mon
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : mia.airport
State Reference	FL
Altitude	msl single value : 15000
Environment
Light	Night
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Navigation In Use	other vortac
Flight Phase	climbout : intermediate altitude
Route In Use	departure sid : ns
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	433366
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial pilot : multi engine
Events
Anomaly	aircraft equipment problem : critical other anomaly
Independent Detector	other flight crewa other flight crewb other other : 4
Resolutory Action	flight crew : landed as precaution flight crew : diverted to another airport other
Consequence	other other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

After takeoff mia at 15000 ft, we noticed electrical smoke smell in cockpit. We elected to return mia and run appropriate checklists. After arrival at gate, ground personnel informed us a landing light was still on. The switch was off. Maintenance man removed light panel from overhead and found burned switch and wire for right landing light. He replaced panel and we re-departed mia. Time from takeoff to landing was less than 10 mins. The circuit breaker, 7.5 amps, did not pop. Interesting, huh? Callback conversation with reporter revealed the following information: the captain called back and stated that he didn't know if this was an ongoing problem with the 757's. The switch had failed and was burned out as was the wire in the panel. He felt that the spike of what ever burned the switch had failed to trip the circuit breaker. The company had called him twice, saying that they were inspecting the switch but did not add anymore information to the questions. He doesn't know if the gear sensor switch was changed, he knew nothing about a problem there. He did not get feedback from the ground crew as to the landing light being bright or dim at the ramp. So far as he knows, the circuit breaker panel or circuit was not changed.

Original NASA ASRS Text

Title: A B757-200 IS MANDATED TO PERFORM A RETURN AND LAND WHEN THE FLC SMELLS AN ELECTRICAL BURNING ODOR IN THE COCKPIT. A CIRCUIT BREAKER HAD FAILED TO DEACTIVATE THE LNDG LIGHT CIRCUIT. THE LNDG LIGHT REMAINED ON WITH THE SWITCH IN THE OFF POS.

Narrative: AFTER TKOF MIA AT 15000 FT, WE NOTICED ELECTRICAL SMOKE SMELL IN COCKPIT. WE ELECTED TO RETURN MIA AND RUN APPROPRIATE CHKLISTS. AFTER ARR AT GATE, GND PERSONNEL INFORMED US A LNDG LIGHT WAS STILL ON. THE SWITCH WAS OFF. MAINT MAN REMOVED LIGHT PANEL FROM OVERHEAD AND FOUND BURNED SWITCH AND WIRE FOR R LNDG LIGHT. HE REPLACED PANEL AND WE RE-DEPARTED MIA. TIME FROM TKOF TO LNDG WAS LESS THAN 10 MINS. THE CIRCUIT BREAKER, 7.5 AMPS, DID NOT POP. INTERESTING, HUH? CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE CAPTAIN CALLED BACK AND STATED THAT HE DIDN'T KNOW IF THIS WAS AN ONGOING PROBLEM WITH THE 757'S. THE SWITCH HAD FAILED AND WAS BURNED OUT AS WAS THE WIRE IN THE PANEL. HE FELT THAT THE SPIKE OF WHAT EVER BURNED THE SWITCH HAD FAILED TO TRIP THE CIRCUIT BREAKER. THE COMPANY HAD CALLED HIM TWICE, SAYING THAT THEY WERE INSPECTING THE SWITCH BUT DID NOT ADD ANYMORE INFORMATION TO THE QUESTIONS. HE DOESN'T KNOW IF THE GEAR SENSOR SWITCH WAS CHANGED, HE KNEW NOTHING ABOUT A PROBLEM THERE. HE DID NOT GET FEEDBACK FROM THE GROUND CREW AS TO THE LANDING LIGHT BEING BRIGHT OR DIM AT THE RAMP. SO FAR AS HE KNOWS, THE CIRCUIT BREAKER PANEL OR CIRCUIT WAS NOT CHANGED.

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.

A B757-200 is mandated to perform a return and land when the flight crew smells an electrical burning odor in the cockpit. A circuit breaker had failed to deactivate the landing light circuit. The landing light remained on with the switch in the off position.