Narrative:

During cruise at FL310, 40 DME east of cle, a strong acrid smoke odor was smelled, and visually a wispy smoke coming from the autoplt vertical speed wheel. Crew declared an emergency and made an emergency landing at cle. Crew accomplished the emergency checklist for electrical/fire and smoke, as well as smoke removal checklists. Landed at cle, was met by cle crash fire rescue equipment. Crash fire rescue equipment boarded aircraft and verified smoke smell, and checked out the aircraft cockpit and east&east compartments for fire and smoke, found none, then took crew and checked crew for smoke inhalation. Crew checked out ok. Maintenance found that the autoplt controller had been smoking and was hot, then disconnected it and removed for inspection and found to be inoperative. The aircraft was then redispatched after maintenance was performed, was dispatched per MEL to iln. Callback conversation with reporter revealed the following information: reporter stated the wisps of smoke and heavy electrical burning odor came from the autoplt pedestal controller. The reporter said strangely the autoplt continued to operate normally. The reporter stated no circuit breakers were tripped during this time but the crew took action and pulled all breakers associated with the autoplt and had control of the smoke. The reporter said the autoplt controller had recently been overhauled.

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Original NASA ASRS Text

Title: A DC9-30 IN CRUISE AT FL310 DECLARED AN EMER AND DIVERTED DUE TO SMOKE AND ELECTRICAL ODOR IN THE COCKPIT CAUSED BY AN AUTOPLT PEDESTAL CONTROLLER MALFUNCTION.

Narrative: DURING CRUISE AT FL310, 40 DME E OF CLE, A STRONG ACRID SMOKE ODOR WAS SMELLED, AND VISUALLY A WISPY SMOKE COMING FROM THE AUTOPLT VERT SPD WHEEL. CREW DECLARED AN EMER AND MADE AN EMER LNDG AT CLE. CREW ACCOMPLISHED THE EMER CHKLIST FOR ELECTRICAL/FIRE AND SMOKE, AS WELL AS SMOKE REMOVAL CHKLISTS. LANDED AT CLE, WAS MET BY CLE CFR. CFR BOARDED ACFT AND VERIFIED SMOKE SMELL, AND CHKED OUT THE ACFT COCKPIT AND E&E COMPARTMENTS FOR FIRE AND SMOKE, FOUND NONE, THEN TOOK CREW AND CHKED CREW FOR SMOKE INHALATION. CREW CHKED OUT OK. MAINT FOUND THAT THE AUTOPLT CONTROLLER HAD BEEN SMOKING AND WAS HOT, THEN DISCONNECTED IT AND REMOVED FOR INSPECTION AND FOUND TO BE INOP. THE ACFT WAS THEN REDISPATCHED AFTER MAINT WAS PERFORMED, WAS DISPATCHED PER MEL TO ILN. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THE WISPS OF SMOKE AND HVY ELECTRICAL BURNING ODOR CAME FROM THE AUTOPLT PEDESTAL CTLR. THE RPTR SAID STRANGELY THE AUTOPLT CONTINUED TO OPERATE NORMALLY. THE RPTR STATED NO CIRCUIT BREAKERS WERE TRIPPED DURING THIS TIME BUT THE CREW TOOK ACTION AND PULLED ALL BREAKERS ASSOCIATED WITH THE AUTOPLT AND HAD CTL OF THE SMOKE. THE RPTR SAID THE AUTOPLT CTLR HAD RECENTLY BEEN OVERHAULED.

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.