Narrative:

En route fcw-cbf experienced fairly sudden complete nighttime electrical failure in C310C. First noted ammeter at '0' approximately 30 mi from destination, so lightened electrical load to transponder and 1 radio. Was at 8500 ft, and was just ready to start descent when was handed off from center to approach. At that time was told that transponder had been intermittent for past 30-40 mi. Prior to that, ammeter needle (part of my usual scan) was 2 ticks to plus side. Attempted to recycle alternators several times without success. Batteries failed less than 10 mins after ammeter noted to be at '0.' after slowing to gear speed in descent, attempted to lower gear via gear switch, but insufficient power left to do so. Continued to home field, as was closest field ahead near reasonable sized city. Made numerous circuits of airport flying with flashlight (engines producing power well) while attempting to manually lower gear. Gear crank-handle would turn one way to end of train, in opposite direction could turn approximately 5-7 turns, and would bind and not crank beyond this point. Recall at least 6 attempts to free mechanism, last several quite forcefully, without success. Therefore, opted to land at uncontrolled home field (runway lights were on) rather than proceed to nearby controled airport with commercial traffic since aircraft was unlighted and presumed no transponder, and I was flying by flashlight. Landed gear up. No personal injury, but understand that airplane considered 'totaled' by insurance company because cost to repair belly skin, plus cost to overhaul engines, exceeded insurance coverage/value of airplane. Contributing factors: airplane has history of electrical problems. When first flown solo by me, as well as during chkout, had problems getting alternators to come on-line at start-up. Plane was in maintenance for over 6 weeks 'to replace alternator.' airplane known to have been landed on belly at least twice previously, once by owner who could not get nose gear to lock down, once by previous owner for reasons unknown. Annual inspection completed earlier the week of this flight by owner (a&P) and signed off by a&I. Do not know how thoroughly a&I actually inspected aircraft, were several anomalies noted during return flight -- intermittent fuel gauge function, was asked afterwards by owner about possible surging right engine and electrical fuel pump function. No checklist, separate from poh, was available, so had to read emergency checklist, emergency procedures by flashlight from book. After jacking up aircraft to move off runway, entered cockpit and attempted to lower gear manually. After turning crank handle, hit same binding that occurred in-flight. Turned handle in opposite direction, to end of mechanism train, when FBO employee entered cockpit and accused me of ruining airplane by not knowing which way to turn handle to lower gear. I turned crank handle again, as forcefully as possible, and again felt the binding, but yanked handle through the bind. As I did this, I felt, more than heard, a sharp 'snap.' gear appeared to almost fall into down position and green 'down and locked' light appeared within 7-10 turns (poh states to expect 60 turns). Did find discussion of incident, at my initiation, with FAA accident prevention counselor and with chief pilot at another FBO, to be very helpful, eg, what else could I have done, what should I have done.

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Original NASA ASRS Text

Title: PVT PLT OF A C310 LOST ALL ELECTRICAL PWR ON A NIGHT XCOUNTRY FLT RESULTING IN A GEAR UP LNDG WHEN THE GEAR COULD NOT BE EXTENDED MANUALLY. THE ACFT RECEIVED DAMAGE TO THE PROPS, ENGS AND UNDER SKIN, BUT WAS NOT CLASSIFIED AS AN ACCIDENT.

Narrative: ENRTE FCW-CBF EXPERIENCED FAIRLY SUDDEN COMPLETE NIGHTTIME ELECTRICAL FAILURE IN C310C. FIRST NOTED AMMETER AT '0' APPROX 30 MI FROM DEST, SO LIGHTENED ELECTRICAL LOAD TO XPONDER AND 1 RADIO. WAS AT 8500 FT, AND WAS JUST READY TO START DSCNT WHEN WAS HANDED OFF FROM CTR TO APCH. AT THAT TIME WAS TOLD THAT XPONDER HAD BEEN INTERMITTENT FOR PAST 30-40 MI. PRIOR TO THAT, AMMETER NEEDLE (PART OF MY USUAL SCAN) WAS 2 TICKS TO PLUS SIDE. ATTEMPTED TO RECYCLE ALTERNATORS SEVERAL TIMES WITHOUT SUCCESS. BATTERIES FAILED LESS THAN 10 MINS AFTER AMMETER NOTED TO BE AT '0.' AFTER SLOWING TO GEAR SPD IN DSCNT, ATTEMPTED TO LOWER GEAR VIA GEAR SWITCH, BUT INSUFFICIENT PWR LEFT TO DO SO. CONTINUED TO HOME FIELD, AS WAS CLOSEST FIELD AHEAD NEAR REASONABLE SIZED CITY. MADE NUMEROUS CIRCUITS OF ARPT FLYING WITH FLASHLIGHT (ENGS PRODUCING PWR WELL) WHILE ATTEMPTING TO MANUALLY LOWER GEAR. GEAR CRANK-HANDLE WOULD TURN ONE WAY TO END OF TRAIN, IN OPPOSITE DIRECTION COULD TURN APPROX 5-7 TURNS, AND WOULD BIND AND NOT CRANK BEYOND THIS POINT. RECALL AT LEAST 6 ATTEMPTS TO FREE MECHANISM, LAST SEVERAL QUITE FORCEFULLY, WITHOUT SUCCESS. THEREFORE, OPTED TO LAND AT UNCTLED HOME FIELD (RWY LIGHTS WERE ON) RATHER THAN PROCEED TO NEARBY CTLED ARPT WITH COMMERCIAL TFC SINCE ACFT WAS UNLIGHTED AND PRESUMED NO XPONDER, AND I WAS FLYING BY FLASHLIGHT. LANDED GEAR UP. NO PERSONAL INJURY, BUT UNDERSTAND THAT AIRPLANE CONSIDERED 'TOTALED' BY INSURANCE COMPANY BECAUSE COST TO REPAIR BELLY SKIN, PLUS COST TO OVERHAUL ENGS, EXCEEDED INSURANCE COVERAGE/VALUE OF AIRPLANE. CONTRIBUTING FACTORS: AIRPLANE HAS HISTORY OF ELECTRICAL PROBS. WHEN FIRST FLOWN SOLO BY ME, AS WELL AS DURING CHKOUT, HAD PROBS GETTING ALTERNATORS TO COME ON-LINE AT START-UP. PLANE WAS IN MAINT FOR OVER 6 WKS 'TO REPLACE ALTERNATOR.' AIRPLANE KNOWN TO HAVE BEEN LANDED ON BELLY AT LEAST TWICE PREVIOUSLY, ONCE BY OWNER WHO COULD NOT GET NOSE GEAR TO LOCK DOWN, ONCE BY PREVIOUS OWNER FOR REASONS UNKNOWN. ANNUAL INSPECTION COMPLETED EARLIER THE WK OF THIS FLT BY OWNER (A&P) AND SIGNED OFF BY A&I. DO NOT KNOW HOW THOROUGHLY A&I ACTUALLY INSPECTED ACFT, WERE SEVERAL ANOMALIES NOTED DURING RETURN FLT -- INTERMITTENT FUEL GAUGE FUNCTION, WAS ASKED AFTERWARDS BY OWNER ABOUT POSSIBLE SURGING R ENG AND ELECTRICAL FUEL PUMP FUNCTION. NO CHKLIST, SEPARATE FROM POH, WAS AVAILABLE, SO HAD TO READ EMER CHKLIST, EMER PROCS BY FLASHLIGHT FROM BOOK. AFTER JACKING UP ACFT TO MOVE OFF RWY, ENTERED COCKPIT AND ATTEMPTED TO LOWER GEAR MANUALLY. AFTER TURNING CRANK HANDLE, HIT SAME BINDING THAT OCCURRED INFLT. TURNED HANDLE IN OPPOSITE DIRECTION, TO END OF MECHANISM TRAIN, WHEN FBO EMPLOYEE ENTERED COCKPIT AND ACCUSED ME OF RUINING AIRPLANE BY NOT KNOWING WHICH WAY TO TURN HANDLE TO LOWER GEAR. I TURNED CRANK HANDLE AGAIN, AS FORCEFULLY AS POSSIBLE, AND AGAIN FELT THE BINDING, BUT YANKED HANDLE THROUGH THE BIND. AS I DID THIS, I FELT, MORE THAN HEARD, A SHARP 'SNAP.' GEAR APPEARED TO ALMOST FALL INTO DOWN POS AND GREEN 'DOWN AND LOCKED' LIGHT APPEARED WITHIN 7-10 TURNS (POH STATES TO EXPECT 60 TURNS). DID FIND DISCUSSION OF INCIDENT, AT MY INITIATION, WITH FAA ACCIDENT PREVENTION COUNSELOR AND WITH CHIEF PLT AT ANOTHER FBO, TO BE VERY HELPFUL, EG, WHAT ELSE COULD I HAVE DONE, WHAT SHOULD I HAVE DONE.

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.