Narrative:

Had just reached cruise altitude of 7500 ft (10 mins). Suddenly lost radio stack, transponder and HSI. Turned radio master offirst officern -- no help. Then turned everything off, turned 1 radio on and it worked. Turned 180 degrees to return to sat. Contacted ATC, but they could not hear me well until I returned to about 30 NM out. I requested landing at sat. I was put in a holding pattern outside the class C airspace for a few mins. Then the controller talked me in to the airport. No power so I had to hand pump the gear down. No flaps (they are electric). Switched to the tower. Tower called out the crash vehicles. Gauges in the plane showed the gear down. Landing was without incident. Taxied to the maintenance hangar and the mechanic on duty began an inspection to determine the cause of the power failure. The alternator seemed to be the prime suspect. I did not try to reset the alternator circuit as outlined in the emergency procedures. Even if it had worked, I would still have returned to sat. Callback conversation with reporter revealed the following information: reporter states that, initially, approach control was not going to let the reporter return land at sat. He was able to give them landmarks to define his position, though, which aided their ability to help him. Reporter stated that the alternator circuit breaker was reset by maintenance and he has not since experienced any problems.

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Original NASA ASRS Text

Title: AN MO2J PLT EXPERIENCED AN ELECTRICAL FAILURE 10 MINS AFTER DEP. AFTER TURNING ALL ELECTRICAL EQUIP OFF, HE WAS ABLE TO USE 1 RADIO TO REESTABLISH COM WITH DEP CTL. THE CTLR VECTORED HIM FOR A RETURN LAND AND THE TWR NOTIFIED CFR. RETURN LAND.

Narrative: HAD JUST REACHED CRUISE ALT OF 7500 FT (10 MINS). SUDDENLY LOST RADIO STACK, XPONDER AND HSI. TURNED RADIO MASTER OFF/ON -- NO HELP. THEN TURNED EVERYTHING OFF, TURNED 1 RADIO ON AND IT WORKED. TURNED 180 DEGS TO RETURN TO SAT. CONTACTED ATC, BUT THEY COULD NOT HEAR ME WELL UNTIL I RETURNED TO ABOUT 30 NM OUT. I REQUESTED LNDG AT SAT. I WAS PUT IN A HOLDING PATTERN OUTSIDE THE CLASS C AIRSPACE FOR A FEW MINS. THEN THE CTLR TALKED ME IN TO THE ARPT. NO PWR SO I HAD TO HAND PUMP THE GEAR DOWN. NO FLAPS (THEY ARE ELECTRIC). SWITCHED TO THE TWR. TWR CALLED OUT THE CRASH VEHICLES. GAUGES IN THE PLANE SHOWED THE GEAR DOWN. LNDG WAS WITHOUT INCIDENT. TAXIED TO THE MAINT HANGAR AND THE MECH ON DUTY BEGAN AN INSPECTION TO DETERMINE THE CAUSE OF THE PWR FAILURE. THE ALTERNATOR SEEMED TO BE THE PRIME SUSPECT. I DID NOT TRY TO RESET THE ALTERNATOR CIRCUIT AS OUTLINED IN THE EMER PROCS. EVEN IF IT HAD WORKED, I WOULD STILL HAVE RETURNED TO SAT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATES THAT, INITIALLY, APCH CTL WAS NOT GOING TO LET THE RPTR RETURN LAND AT SAT. HE WAS ABLE TO GIVE THEM LANDMARKS TO DEFINE HIS POS, THOUGH, WHICH AIDED THEIR ABILITY TO HELP HIM. RPTR STATED THAT THE ALTERNATOR CIRCUIT BREAKER WAS RESET BY MAINT AND HE HAS NOT SINCE EXPERIENCED ANY PROBS.

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.