Narrative:

I was in the main cabin near the window exits and noticed 2 things: 1) a grayish blue haze in the cabin forward of the window exits, and 2) a smell like plastic, oil or electrical type, but not noxious, just slight. I immediately went to the cockpit. They were busy and had their oxygen masks on. The same blue haze was present there and came pouring out of the cockpit. In mins, the air was clear and the odor gone. The cabin pressurization was a little messed up. I was getting a slight unbalanced feeling, but not terribly, so we returned to ord without incident at XB20. After arrival, the mechanic asked us about the color of the smoke/haze. One note: the air conditioning system on this aircraft had been fixed that morning just prior to departure. The cabin pressurization was an additional mechanical problem incurred during this flight segment. There was no critical emergency situation, just a strange occurrence. Also, the F100 has many APU, pac system failures. Lots of electrical glitches that seem to result in mechanical problems often.

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Original NASA ASRS Text

Title: CABIN ATTENDANT RPT, FOKKER 100, ORD-DCA. ON CLBOUT, CRUISE, BLUE HAZE AND ELECTRICAL SMELL IN CABIN, COCKPIT. RETURN TO ORD.

Narrative: I WAS IN THE MAIN CABIN NEAR THE WINDOW EXITS AND NOTICED 2 THINGS: 1) A GRAYISH BLUE HAZE IN THE CABIN FORWARD OF THE WINDOW EXITS, AND 2) A SMELL LIKE PLASTIC, OIL OR ELECTRICAL TYPE, BUT NOT NOXIOUS, JUST SLIGHT. I IMMEDIATELY WENT TO THE COCKPIT. THEY WERE BUSY AND HAD THEIR OXYGEN MASKS ON. THE SAME BLUE HAZE WAS PRESENT THERE AND CAME POURING OUT OF THE COCKPIT. IN MINS, THE AIR WAS CLR AND THE ODOR GONE. THE CABIN PRESSURIZATION WAS A LITTLE MESSED UP. I WAS GETTING A SLIGHT UNBALANCED FEELING, BUT NOT TERRIBLY, SO WE RETURNED TO ORD WITHOUT INCIDENT AT XB20. AFTER ARR, THE MECH ASKED US ABOUT THE COLOR OF THE SMOKE/HAZE. ONE NOTE: THE AIR CONDITIONING SYS ON THIS ACFT HAD BEEN FIXED THAT MORNING JUST PRIOR TO DEP. THE CABIN PRESSURIZATION WAS AN ADDITIONAL MECHANICAL PROB INCURRED DURING THIS FLT SEGMENT. THERE WAS NO CRITICAL EMER SIT, JUST A STRANGE OCCURRENCE. ALSO, THE F100 HAS MANY APU, PAC SYS FAILURES. LOTS OF ELECTRICAL GLITCHES THAT SEEM TO RESULT IN MECHANICAL PROBS OFTEN.

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.