Narrative:

In the descent (en route from lga-pwm) passing approximately 14000 ft, a sudden and intense smell of electrical smoke was present. Emergency actions pertaining to smoke in cockpit were taken. Captain and copilot simultaneously agreed to divert immediately to psm which was immediately below us. An emergency was declared to ZBW (frequency 128.20) and an expeditious descent was initiated. At the same time the decision was made to land at psm, a passenger (later learned he was a private pilot) came up to the cockpit and said he too smelled and saw smoke in the cabin/cockpit. The passenger were briefed for the landing which was uneventful in itself. The airplane was brought to a stop just clear of the runway on a taxiway. The aircraft was shut down and passenger evacuate/evacuationed through the normal, main cabin door and escorted away from the airplane. The aircraft did not sustain any damage and all passenger and crew were safe and accounted for. The first officer, who had breathed in a few more breaths of contaminated air, complained of a tight feeling in his throat and chest and a headache. The captain and first officer performed the emergency actions and made a quick determination that it was best to land immediately given the strong odor and haze of smoke and the fact that a perfect landing site, complete with emergency equipment was right under the airplane. Both the captain and first officer live and have flown extensively in new england and were very familiar with pease and the surrounding area. I believe that this helped in making the determination to land and ultimately the successful outcome of this event. Sometimes a few seconds can make all the difference in a situation like this. Callback conversation with reporter revealed the following information: the reporter stated the problem was caused by a passenger cabin temperature controller located in the passenger cabin ceiling. The reporter stated the circuit breaker for this unit is located in the cabin and is not close to the cockpit. The reporter said the circuit breaker did not open the circuit and prevent the overheating of the controller.

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Original NASA ASRS Text

Title: A BEECH 1900D IN DSCNT AT 14000 FT DECLARED AN EMER AND DIVERTED DUE TO SMOKE AND ELECTRICAL ODOR CAUSED BY AN OVERHEATED CABIN TEMP CTLR.

Narrative: IN THE DSCNT (ENRTE FROM LGA-PWM) PASSING APPROX 14000 FT, A SUDDEN AND INTENSE SMELL OF ELECTRICAL SMOKE WAS PRESENT. EMER ACTIONS PERTAINING TO SMOKE IN COCKPIT WERE TAKEN. CAPT AND COPLT SIMULTANEOUSLY AGREED TO DIVERT IMMEDIATELY TO PSM WHICH WAS IMMEDIATELY BELOW US. AN EMER WAS DECLARED TO ZBW (FREQ 128.20) AND AN EXPEDITIOUS DSCNT WAS INITIATED. AT THE SAME TIME THE DECISION WAS MADE TO LAND AT PSM, A PAX (LATER LEARNED HE WAS A PVT PLT) CAME UP TO THE COCKPIT AND SAID HE TOO SMELLED AND SAW SMOKE IN THE CABIN/COCKPIT. THE PAX WERE BRIEFED FOR THE LNDG WHICH WAS UNEVENTFUL IN ITSELF. THE AIRPLANE WAS BROUGHT TO A STOP JUST CLR OF THE RWY ON A TXWY. THE ACFT WAS SHUT DOWN AND PAX EVACED THROUGH THE NORMAL, MAIN CABIN DOOR AND ESCORTED AWAY FROM THE AIRPLANE. THE ACFT DID NOT SUSTAIN ANY DAMAGE AND ALL PAX AND CREW WERE SAFE AND ACCOUNTED FOR. THE FO, WHO HAD BREATHED IN A FEW MORE BREATHS OF CONTAMINATED AIR, COMPLAINED OF A TIGHT FEELING IN HIS THROAT AND CHEST AND A HEADACHE. THE CAPT AND FO PERFORMED THE EMER ACTIONS AND MADE A QUICK DETERMINATION THAT IT WAS BEST TO LAND IMMEDIATELY GIVEN THE STRONG ODOR AND HAZE OF SMOKE AND THE FACT THAT A PERFECT LNDG SITE, COMPLETE WITH EMER EQUIP WAS RIGHT UNDER THE AIRPLANE. BOTH THE CAPT AND FO LIVE AND HAVE FLOWN EXTENSIVELY IN NEW ENGLAND AND WERE VERY FAMILIAR WITH PEASE AND THE SURROUNDING AREA. I BELIEVE THAT THIS HELPED IN MAKING THE DETERMINATION TO LAND AND ULTIMATELY THE SUCCESSFUL OUTCOME OF THIS EVENT. SOMETIMES A FEW SECONDS CAN MAKE ALL THE DIFFERENCE IN A SIT LIKE THIS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE PROB WAS CAUSED BY A PAX CABIN TEMP CTLR LOCATED IN THE PAX CABIN CEILING. THE RPTR STATED THE CIRCUIT BREAKER FOR THIS UNIT IS LOCATED IN THE CABIN AND IS NOT CLOSE TO THE COCKPIT. THE RPTR SAID THE CIRCUIT BREAKER DID NOT OPEN THE CIRCUIT AND PREVENT THE OVERHEATING OF THE CTLR.

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.