Loss of electrical power en route.

Attributes
ACN	279867
Time
Date	199408
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : mqo airport : sbp
State Reference	CA
Altitude	msl bound lower : 7000 msl bound upper : 7000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : sbp
Operator	general aviation : personal
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	cruise other
Route In Use	enroute airway : zla
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : commercial pilot : instrument
Experience	flight time last 90 days : 33 flight time total : 487 flight time type : 64
ASRS Report	279867
Person 2
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : unable other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

En route from monterey to santa monica, digital ammeter showed reading of 000-001. Notified ZOA of possible alternator failure and desire to continue while trouble- shooting (all this approximately 15 mins after departure mry). Turned off all unnecessary equipment (ADF, DME, lights, 2ND navigation/communication, etc). Soon after check-in with ZLA near frams intersection on v- 27, radio got weak. Notified ZLA with request to divert santa maria. Center advised closest airport san luis obispo. Almost immediately after acknowledgement, the GPS went out then the #1 navigation/communication. I changed squawk to 7600 and began descent to san luis obispo. Also lowered gear and got 3 green (weak) lights. In descent the overhead speaker began to make a lot of static type noise -- very loud. Center had advised the tower of my electrical failure and received green light on long final. Intentionally bounced on left main on landing approach to prove down and locked (lights out by this time). Uneventful no flap landing. Cause of problem: air conditioning fan belt had snapped and caused alternator fan belt to come off pulleys.

Original NASA ASRS Text

Title: LOSS OF ELECTRICAL PWR ENRTE.

Narrative: ENRTE FROM MONTEREY TO SANTA MONICA, DIGITAL AMMETER SHOWED READING OF 000-001. NOTIFIED ZOA OF POSSIBLE ALTERNATOR FAILURE AND DESIRE TO CONTINUE WHILE TROUBLE- SHOOTING (ALL THIS APPROX 15 MINS AFTER DEP MRY). TURNED OFF ALL UNNECESSARY EQUIP (ADF, DME, LIGHTS, 2ND NAV/COM, ETC). SOON AFTER CHK-IN WITH ZLA NEAR FRAMS INTXN ON V- 27, RADIO GOT WEAK. NOTIFIED ZLA WITH REQUEST TO DIVERT SANTA MARIA. CTR ADVISED CLOSEST ARPT SAN LUIS OBISPO. ALMOST IMMEDIATELY AFTER ACKNOWLEDGEMENT, THE GPS WENT OUT THEN THE #1 NAV/COM. I CHANGED SQUAWK TO 7600 AND BEGAN DSCNT TO SAN LUIS OBISPO. ALSO LOWERED GEAR AND GOT 3 GREEN (WEAK) LIGHTS. IN DSCNT THE OVERHEAD SPEAKER BEGAN TO MAKE A LOT OF STATIC TYPE NOISE -- VERY LOUD. CTR HAD ADVISED THE TWR OF MY ELECTRICAL FAILURE AND RECEIVED GREEN LIGHT ON LONG FINAL. INTENTIONALLY BOUNCED ON L MAIN ON LNDG APCH TO PROVE DOWN AND LOCKED (LIGHTS OUT BY THIS TIME). UNEVENTFUL NO FLAP LNDG. CAUSE OF PROB: AIR CONDITIONING FAN BELT HAD SNAPPED AND CAUSED ALTERNATOR FAN BELT TO COME OFF PULLEYS.

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.