Narrative:

We were flying back to beverly, setting up to do a practice approach, when a circuit breaker popped and the high voltage light came on. I grabbed the poh and the emergency checklist. Within a few mins we began to lose our radios and all navaids. We followed the checklist and recycled the master switch but nothing happened. So now, with only flashlights, we searched for a place to land. Approximately 10 mi south was hanscom AFB (bedford airport) so we headed for the airport. As we began our descent, the engine was really rough and was coughing if pulled back to idle. We observed that no one was in the traffic pattern so we headed for the nearest runway. We landed on runway 11, taxied to FBO where massport came and picked us up. We spoke to the flight center, who was on their way, and the tower to explain what had happened.

Google
 

Original NASA ASRS Text

Title: C172 PLT MADE AN EMER LNDG ON MIL BASE WITHOUT CONTACTING TWR DUE TO LOSS OF RADIOS FROM OVERLOADING THE ALTERNATOR CAPACITY.

Narrative: WE WERE FLYING BACK TO BEVERLY, SETTING UP TO DO A PRACTICE APCH, WHEN A CIRCUIT BREAKER POPPED AND THE HIGH VOLTAGE LIGHT CAME ON. I GRABBED THE POH AND THE EMER CHKLIST. WITHIN A FEW MINS WE BEGAN TO LOSE OUR RADIOS AND ALL NAVAIDS. WE FOLLOWED THE CHKLIST AND RECYCLED THE MASTER SWITCH BUT NOTHING HAPPENED. SO NOW, WITH ONLY FLASHLIGHTS, WE SEARCHED FOR A PLACE TO LAND. APPROX 10 MI S WAS HANSCOM AFB (BEDFORD ARPT) SO WE HEADED FOR THE ARPT. AS WE BEGAN OUR DSCNT, THE ENG WAS REALLY ROUGH AND WAS COUGHING IF PULLED BACK TO IDLE. WE OBSERVED THAT NO ONE WAS IN THE TFC PATTERN SO WE HEADED FOR THE NEAREST RWY. WE LANDED ON RWY 11, TAXIED TO FBO WHERE MASSPORT CAME AND PICKED US UP. WE SPOKE TO THE FLT CTR, WHO WAS ON THEIR WAY, AND THE TWR TO EXPLAIN WHAT HAD HAPPENED.

Data retrieved from NASA's ASRS site as of July 2007 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.