19981023044769I

The beginning of the last flight was not unusual, except that I was held on the gorund for about 15 or 20 minutes longer than normal because of the large volume of departing commercial traffic at the san jose airport. My takeoff was sometime before 3:30 pm. To the best of my recollection both the digital voltmeter and the analog ammeter were normal at start-up, but upon departing to the east, I noted the digital readout of the dvor was a little weak. About 20 minutes or so into the flight (normally a 55 minute flight to touchdown),the readout of the loran began to flicker. At that time I thought the problem was only in the avionics and began to throw switches attempting to locate the "loose connection." Upon toggling the nav. Lights, the entire panel went blank, except for the display on the #2 king radio. When I switched to that radio's display, it also went blank. I then turned everything off except for the transponder. During my 2500 hours of flight time I have had to contend with numerous avionics problems, so I was not concerned at this stage of the flight. I "knew" it was a panel problem somehow connected with the autopilot failure. I had no radios, nav. Equipment or panel lights, but I would arrive before dark, I knew the airplane, the airport, and the terrain. I don't remember seeing the coltmeter, probably because it was also blank, but I recall seeing the ammeter needle in the normal position. The lack of radios were my main concern, because of the Friday evening traffic at Truckee. I planned and flew a wide right downwind and right base to runway 19 to make sure I could locate all aircraft in the pattern. I had called Truckee on the telephone before I left san jose for weather and was told the active runway was 19. Upon crossing donner ridge, I dropped 10 degrees of flaps (speed flaps) to slow the plane and begin my descent. I also began my "near airport" scan,looking for traffic. At the 45 entry I dropped my gear. Everything seemed normal except for the lack of gear and flap lights. I heard the rushing sound of the wind as the gear was lowered, experienced the usual change in airspeed and noted the mechanical flag was down. On downwind, just before turning base I tried to add another 20 degrees of flaps, but nothing happened. At that point I realized I had an electrical problem and most likely had lost the alternator. While some aspects of the flight prior to this point may be a little fuzzy, my decisions after I realized I had an electrical problem are quite clear in my memory. The book calls for pulling the circuit breaker and cranking down the wheels, and for an emergency landing, to pull the mixture with the alternator, I was concerned that somehow the engine might become damaged. The runway was open (no traffic observed on the airport or in the pattern), dusk was approaching and the gear seemed to be down, I therefore elected to continue the approach. I din not pull the circuit breaker, but I did remove the crank cover and attempt to turn the carnk. It seemed to be down, but I had no way of knowing it it was fully locked (both the lights and horn were out) I left the circuit breaker closed because I wanted to use any power left in the battery to assist in securing the gear. I also elected to keep the engine running in order to make a power-on-landing, touching down as slowly as possible and keeping the nose up off the front wheel. While I was prepared for gear collapse (I opened the door latch on final), I really expected to land and then taxi directly to todd aero to have my problems sorted out. Shortly after touch down the right gear collapsed and then in sequence, front wheel and the left folded. The airplane skidded to the right, coming to rest on the right shoulder of the pavement, several hundred feet from the point of touchdown. I left the airplane and began walking to the airport center for assistance, and to pick up my car. When the engine cowling was removed in order to lift the airplane onto a cart for transfer to a hanger, I could see the alternator was loose, and could rotate it back and forth. Upon close inspection in the hanger, the bolt holes through the front flange were found to be badly worn, enlarged and misshapened. The bolts, while safety wired, were loose. The magnitude of wear suggest the alternator problem has existed for several years. Pictures have been taken.