Narrative:

Shortly after we departed we noticed a slight electrical type smell. After about 20 minutes; the odor became significantly worse and smelled of burning wire but there was no visible smoke. The flight attendants had no odor in the cabin. We accomplished the memory items for smoke/fumes in the checklist; declared an emergency; and got the plane pointed back to our departure airport. We requested a descent to below 10;000 ft and were cleared pilot's discretion to 3000 ft. We shot a quick message to dispatch and leveled at 7000 ft. We completed the aircraft smoke/fume removal checklist but it didn't help. I told the flight attendants and passengers that we were returning because of fumes in the cockpit. We requested crash fire rescue equipment to standby and give us the once over after we land. Approach/landing was uneventful and the fire department cleared us to the gate. At the gate; we deplaned the passengers.

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Original NASA ASRS Text

Title: A B737-300 returned to its departure airport when burning electrical odors and fumes were detected in the cockpit.

Narrative: Shortly after we departed we noticed a slight electrical type smell. After about 20 minutes; the odor became significantly worse and smelled of burning wire but there was no visible smoke. The Flight Attendants had no odor in the cabin. We accomplished the memory items for Smoke/Fumes in the checklist; declared an emergency; and got the plane pointed back to our departure airport. We requested a descent to below 10;000 FT and were cleared pilot's discretion to 3000 FT. We shot a quick message to Dispatch and leveled at 7000 FT. We completed the Aircraft Smoke/Fume Removal checklist but it didn't help. I told the Flight Attendants and Passengers that we were returning because of fumes in the cockpit. We requested CFR to standby and give us the once over after we land. Approach/landing was uneventful and the Fire Department cleared us to the gate. At the gate; we deplaned the passengers.

Data retrieved from NASA's ASRS site as of April 2012 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.