Narrative:

I was PF. We had just swapped into a different aircraft. That aircraft had just been released by maintenance and engine run-ups were performed by a different crew. Just after takeoff, when the first officer brought the bleed air system to the environmental mode to pressurize the airplane, we both noticed an unusual smell. At first we thought it may have been electrical (as in an electrical fire), but no smoke was noted. I checked to see that the windshield heat was off and it had been since takeoff. We advised tower that we would like to return. By the time we were on downwind, the smell began to subside. We elected not to deploy any oxygen. The passenger were notified of the situation. We landed without incident. We advised company and had maintenance look at the airplane. After further investigation the cause of the fumes was found to be turbine wash fluid that had been improperly drained from the left engine. When the aircraft pressurized after takeoff it burned and evaporated and was drawn into the cabin. Later that afternoon it was noted that the left engine ice vane system had been disconnected (the actuator ends from the door) and not properly reattached with bolts and nuts. No known FARS were violated to the knowledge of the crew, nor was an emergency declared.

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Original NASA ASRS Text

Title: FLC OF A BEECH 1900 (BE02), RETURNED TO LAND AFTER TKOF DUE TO AN UNUSUAL SMELL COMING FROM THE BLEED AIR FOR PRESSURIZATION.

Narrative: I WAS PF. WE HAD JUST SWAPPED INTO A DIFFERENT ACFT. THAT ACFT HAD JUST BEEN RELEASED BY MAINT AND ENG RUN-UPS WERE PERFORMED BY A DIFFERENT CREW. JUST AFTER TKOF, WHEN THE FO BROUGHT THE BLEED AIR SYS TO THE ENVIRONMENTAL MODE TO PRESSURIZE THE AIRPLANE, WE BOTH NOTICED AN UNUSUAL SMELL. AT FIRST WE THOUGHT IT MAY HAVE BEEN ELECTRICAL (AS IN AN ELECTRICAL FIRE), BUT NO SMOKE WAS NOTED. I CHKED TO SEE THAT THE WINDSHIELD HEAT WAS OFF AND IT HAD BEEN SINCE TKOF. WE ADVISED TWR THAT WE WOULD LIKE TO RETURN. BY THE TIME WE WERE ON DOWNWIND, THE SMELL BEGAN TO SUBSIDE. WE ELECTED NOT TO DEPLOY ANY OXYGEN. THE PAX WERE NOTIFIED OF THE SIT. WE LANDED WITHOUT INCIDENT. WE ADVISED COMPANY AND HAD MAINT LOOK AT THE AIRPLANE. AFTER FURTHER INVESTIGATION THE CAUSE OF THE FUMES WAS FOUND TO BE TURBINE WASH FLUID THAT HAD BEEN IMPROPERLY DRAINED FROM THE L ENG. WHEN THE ACFT PRESSURIZED AFTER TKOF IT BURNED AND EVAPORATED AND WAS DRAWN INTO THE CABIN. LATER THAT AFTERNOON IT WAS NOTED THAT THE L ENG ICE VANE SYS HAD BEEN DISCONNECTED (THE ACTUATOR ENDS FROM THE DOOR) AND NOT PROPERLY REATTACHED WITH BOLTS AND NUTS. NO KNOWN FARS WERE VIOLATED TO THE KNOWLEDGE OF THE CREW, NOR WAS AN EMER DECLARED.

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.