Narrative:

At approximately 6000 ft; on our arrival; we experienced abrupt smoke coming from behind the avionics console below the windscreen. I instructed my first officer to declare an emergency with ATC and tell them we would be landing at a nearby airport and to clear airspace ahead. Also requested him to call ahead to tower and have emergency equipment standing by. After lowering; the nose and applying full throttle; I turned and announced to out passengers (which they were already fully aware) that we had smoke and would land shortly. Approximately 2 to 3 minutes later; we were on the ground surrounded by emergency vehicles. I immediately shutdown the airplane as my first officer evacuated the passengers. Total smoke duration in flight lasted about 30 seconds. Heavy at first; then tapering slowly towards the 30 second or so point. Odor was present; however; no smoke was emitting during final phases of flight or after shutdown. Passengers were fully debriefed and then escorted by our local service representative into the FBO.

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Original NASA ASRS Text

Title: A HS125 flight crew responded to smoke in the cockpit.

Narrative: At approximately 6000 FT; on our arrival; we experienced abrupt smoke coming from behind the avionics console below the windscreen. I instructed my First Officer to declare an emergency with ATC and tell them we would be landing at a nearby airport and to clear airspace ahead. Also requested him to call ahead to tower and have emergency equipment standing by. After lowering; the nose and applying full throttle; I turned and announced to out passengers (which they were already fully aware) that we had smoke and would land shortly. Approximately 2 to 3 minutes later; we were on the ground surrounded by emergency vehicles. I immediately shutdown the airplane as my First Officer evacuated the passengers. Total smoke duration in flight lasted about 30 seconds. Heavy at first; then tapering slowly towards the 30 second or so point. Odor was present; however; no smoke was emitting during final phases of flight or after shutdown. Passengers were fully debriefed and then escorted by our local service representative into the FBO.

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.