Narrative:

Pilot declared emergency during mid flight [reporting] smoke in the cockpit and made an emergency landing at ZZZ. The aircraft had to descend without delay and may have gotten close to another aircraft but I'm not certain. I was called in to assist after the pilot had declared an emergency. He landed safely.

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Original NASA ASRS Text

Title: Enroute controller reported MD-88 had smoke in cockpit; made emergency landing.

Narrative: Pilot declared emergency during mid flight [reporting] smoke in the cockpit and made an emergency landing at ZZZ. The aircraft had to descend without delay and may have gotten close to another aircraft but I'm not certain. I was called in to assist after the Pilot had declared an emergency. He landed safely.

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.