Narrative:

Shortly before the incident I had turned on the landing light when I saw traffic in the area and to prepare for the descent; at this point the aircraft was roughly 20-25 miles from the destination airport. The first spark came from the left side of the nose of the aircraft and flew over the left side of the canopy; minutes after we had turned on the landing light. The second spark came across the same path seconds after the first; at which point I had immediately squawked 7700 and declared an emergency on tower's frequency and turned towards ZZZ; the nearest airport with an open control tower. My passenger; a private pilot who is out of currency; read me the electrical fire checklist; which I decided wasn't the best action because we had no indication on the ammeter; under voltage or over voltage light of an electrical fire or issue. After we reviewed the electrical fire checklist we executed the precautionary landing checklist which covered a normal pre landing check as well as shutting down unnecessary equipment; I turned off the second nav/comm radio; the MX20 multifunction display and unplugged a 24v cigarette lighter charger that had been charging an ipad. Tower immediately cleared us for landing and we set up for a right base and landed while other traffic on the ground was instructed to hold short at their positions. As we landed it seemed there was a fire truck at every exit on the side of the runway; we were instructed to exit by making a left turn and holding short. The fire trucks converged around the left and right front side of the aircraft and one shined some very bright light onto the front of the aircraft. I completed the after landing checklist but kept the aircraft engine running; the firefighters made no movements toward the aircraft and nobody got out of the trucks so I asked for instructions on the tower frequency; and after some confusion over the frequency we received instruction to taxi to the ramp where we shut down the aircraft and the firefighters inspected the engine through the front of the cowling and the inspection door on the top of the cowling; no fire was found.

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Original NASA ASRS Text

Title: BE77 pilot reports sparks from the front of the aircraft shortly after turning on the landing light in preparation for descent. An emergency is declared and the flight diverts to the nearest suitable airport. No fire or electrical anomalies are detected during taxi or after shut down on the ramp.

Narrative: Shortly before the incident I had turned on the landing light when I saw traffic in the area and to prepare for the descent; at this point the aircraft was roughly 20-25 miles from the destination airport. The first spark came from the left side of the nose of the aircraft and flew over the left side of the canopy; minutes after we had turned on the landing light. The second spark came across the same path seconds after the first; at which point I had immediately squawked 7700 and declared an emergency on Tower's frequency and turned towards ZZZ; the nearest airport with an open control tower. My passenger; a private pilot who is out of currency; read me the electrical fire checklist; which I decided wasn't the best action because we had no indication on the ammeter; under voltage or over voltage light of an electrical fire or issue. After we reviewed the electrical fire checklist we executed the precautionary landing checklist which covered a normal pre landing check as well as shutting down unnecessary equipment; I turned off the second nav/comm radio; the MX20 multifunction display and unplugged a 24v cigarette lighter charger that had been charging an iPad. Tower immediately cleared us for landing and we set up for a right base and landed while other traffic on the ground was instructed to hold short at their positions. As we landed it seemed there was a fire truck at every exit on the side of the runway; we were instructed to exit by making a left turn and holding short. The fire trucks converged around the left and right front side of the aircraft and one shined some very bright light onto the front of the aircraft. I completed the after landing checklist but kept the aircraft engine running; the firefighters made no movements toward the aircraft and nobody got out of the trucks so I asked for instructions on the Tower frequency; and after some confusion over the frequency we received instruction to taxi to the ramp where we shut down the aircraft and the firefighters inspected the engine through the front of the cowling and the inspection door on the top of the cowling; no fire was found.

Data retrieved from NASA's ASRS site as of July 2013 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.