Narrative:

After level off [on a ferry flight] at FL400 the first officer went to the back to put some charts away and smelled an acrid smell of electrical smoke; he asked me to confirm the smell; which I did. We donned oxygen masks; performed the emergency checklist; and then notified center of our emergency. We started an emergency descent and center gave us initial vectors to [diversion airport]. After analyzing the situation; we decided that it did not warrant dumping cabin pressure at a high altitude; as the smoke was not a big problem; more of a haze; and did not restrict our visibility. Center read us weather and NOTAM information and handed us off to approach. They had crash fire rescue waiting our arrival; we landed; exited [the runway]; and evacuated the aircraft. The fire department inspected the airplane and noted the smell and haze lingering in the cabin. No apparent damage was visible. The aircraft was towed to [FBO] and put into the hangar. On a special note; I would like to comment that all the ATC controllers did an outstanding job helpings us.

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Original NASA ASRS Text

Title: A CE560EP Captain reported noticing a smell of electrical smoke on reaching cruise altitude. Crew declared emergency and diverted to a nearby airport.

Narrative: After level off [on a ferry flight] at FL400 the First Officer went to the back to put some charts away and smelled an acrid smell of electrical smoke; he asked me to confirm the smell; which I did. We donned oxygen masks; performed the emergency checklist; and then notified Center of our emergency. We started an emergency descent and Center gave us initial vectors to [diversion airport]. After analyzing the situation; we decided that it did not warrant dumping cabin pressure at a high altitude; as the smoke was not a big problem; more of a haze; and did not restrict our visibility. Center read us weather and NOTAM information and handed us off to Approach. They had crash fire rescue waiting our arrival; we landed; exited [the runway]; and evacuated the aircraft. The fire department inspected the airplane and noted the smell and haze lingering in the cabin. No apparent damage was visible. The aircraft was towed to [FBO] and put into the hangar. On a special note; I would like to comment that all the ATC Controllers did an outstanding job helpings us.

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.