Narrative:

On this date; I was performing a check ride with an FAA representative. After completion of the check ride; we returned to the departure airport. While being vectored for the final approach course for the ILS runway 4; cleared direct to the FAF; descend and maintain 2;000 ft; cleared for the ILS approach; I pressed direct to the FAF on the G500 and hit enter then lost all radios; navigation; transponder; GPS; and auto pilot. The 30 amp avionic circuit breaker on the avionics panel popped and was impossible to reset to try and get radios back to communicate with ATC. The aircraft's position at the time of the loss of avionics was on the approach course; without clearance to land. I considered leaving the airspace and remain clear of the airport area. I thought about turning southwest bound; but that would have placed me into head-on traffic being vectored for the final approach course. Straight ahead of me on my present heading would have placed me in conflict with radio towers (roughly 2;200 ft tall); additionally traffic was being vectored overhead so climbing was out of the picture. The safest option was to continue as previously cleared and try and reset the circuit breaker; hoping to communicate with ATC or get light-gun signals for landing. After reducing the electrical load on the aircraft; and letting the circuit breaker cool; a reset was made and the breaker stayed in long enough to communicate; I declared an emergency inside the FAF. During this phase of flight the examiner offered to assist by accomplishing the checklist; at this point the ride was over and he assisted with the problem at hand. After landing; the electrical load was reduced; minus radios and transponder; providing continued communications with ground control. I was cleared to taxi to the FBO where we shut down.

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Original NASA ASRS Text

Title: BE20 Captain reports avionics circuit breaker tripping during ILS approach in VMC. The approach is continued and the circuit breaker is reset and stays in long enough to communicate and declare an emergency.

Narrative: On this date; I was performing a check ride with an FAA Representative. After completion of the check ride; we returned to the departure airport. While being vectored for the final approach course for the ILS Runway 4; cleared direct to the FAF; descend and maintain 2;000 FT; cleared for the ILS approach; I pressed direct to the FAF on the G500 and hit enter then lost all radios; navigation; transponder; GPS; and auto pilot. The 30 amp avionic circuit breaker on the avionics panel popped and was impossible to reset to try and get radios back to communicate with ATC. The aircraft's position at the time of the loss of avionics was on the approach course; without clearance to land. I considered leaving the airspace and remain clear of the airport area. I thought about turning southwest bound; but that would have placed me into head-on traffic being vectored for the final approach course. Straight ahead of me on my present heading would have placed me in conflict with radio towers (roughly 2;200 FT tall); additionally traffic was being vectored overhead so climbing was out of the picture. The safest option was to continue as previously cleared and try and reset the circuit breaker; hoping to communicate with ATC or get light-gun signals for landing. After reducing the electrical load on the aircraft; and letting the circuit breaker cool; a reset was made and the breaker stayed in long enough to communicate; I declared an emergency inside the FAF. During this phase of flight the examiner offered to assist by accomplishing the checklist; at this point the ride was over and he assisted with the problem at hand. After landing; the electrical load was reduced; minus radios and transponder; providing continued communications with Ground Control. I was cleared to taxi to the FBO where we shut down.

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.