Narrative:

We departed msp for ord and during the climb, passing approximately FL210, my first officer and I smelled a strange acrid type odor in the cockpit. I called the lead flight attendant and asked him if something was burning in the ovens and he said that the ovens were off. We then declared an emergency with ATC and started an emergency descent and diversion to rst. I handled the air conditioning smoke checklist while my first officer flew the aircraft. Oxygen masks and goggles were donned. I communicated more with the lead flight attendant, the passenger and with dispatch about the situation. After the emergency checklist was completed the odor was less strong (left pack off). Descent and approach checks were completed and the approach and landing were uneventful. Emergency vehicles were standing by for landing. After landing, I cleared the runway and stopped. I then had the emergency teams inspect the exterior of the aircraft. No smoke/fire was detected by the emergency teams. We then proceeded to the gate for maintenance. After debriefing the crew, we found out that the odor was localized in the cockpit/galley area and was not detected in the main cabin area. At the time of this writing, we are not completely sure of what caused the problem, but the left pack is suspect.

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Original NASA ASRS Text

Title: FLC OF A DC9-40 DECLARED AN EMER AND DIVERTED TO LAND AFTER SMELLING AN ODD ODOR AND SMOKE IN THE COCKPIT AREA. AN UNEVENTFUL LNDG WAS MADE AND EMER CREWS LOOKED OVER ACFT BEFORE PARKING AND PAX DEPLANING. FLC AND MAINT SUSPECT THE L BLEED AIR PACK HAS A LEAK AND CAUSED THE PROB.

Narrative: WE DEPARTED MSP FOR ORD AND DURING THE CLB, PASSING APPROX FL210, MY FO AND I SMELLED A STRANGE ACRID TYPE ODOR IN THE COCKPIT. I CALLED THE LEAD FLT ATTENDANT AND ASKED HIM IF SOMETHING WAS BURNING IN THE OVENS AND HE SAID THAT THE OVENS WERE OFF. WE THEN DECLARED AN EMER WITH ATC AND STARTED AN EMER DSCNT AND DIVERSION TO RST. I HANDLED THE AIR CONDITIONING SMOKE CHKLIST WHILE MY FO FLEW THE ACFT. OXYGEN MASKS AND GOGGLES WERE DONNED. I COMMUNICATED MORE WITH THE LEAD FLT ATTENDANT, THE PAX AND WITH DISPATCH ABOUT THE SIT. AFTER THE EMER CHKLIST WAS COMPLETED THE ODOR WAS LESS STRONG (L PACK OFF). DSCNT AND APCH CHKS WERE COMPLETED AND THE APCH AND LNDG WERE UNEVENTFUL. EMER VEHICLES WERE STANDING BY FOR LNDG. AFTER LNDG, I CLRED THE RWY AND STOPPED. I THEN HAD THE EMER TEAMS INSPECT THE EXTERIOR OF THE ACFT. NO SMOKE/FIRE WAS DETECTED BY THE EMER TEAMS. WE THEN PROCEEDED TO THE GATE FOR MAINT. AFTER DEBRIEFING THE CREW, WE FOUND OUT THAT THE ODOR WAS LOCALIZED IN THE COCKPIT/GALLEY AREA AND WAS NOT DETECTED IN THE MAIN CABIN AREA. AT THE TIME OF THIS WRITING, WE ARE NOT COMPLETELY SURE OF WHAT CAUSED THE PROB, BUT THE L PACK IS SUSPECT.

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.