Viking/Turbo-Viking 17-30/31
Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine
Flight Crew Last 90 Days 17; Flight Crew Total 2803; Flight Crew Type 1824
Time Pressure
Aircraft Equipment Problem Critical; Inflight Event / Encounter Weather / Turbulence
Air Traffic Control Provided Assistance; Flight Crew Landed in Emergency Condition; Flight Crew Diverted
Aircraft
Returning from ZZZ1 to ZZZ2 via ZZZ3 and ZZZ4 most weather stations near ZZZ2 were reporting ceilings of 200 to 500 feet. ZZZ2 has no weather reporting; but since multiple airports were all reporting 400 feet or less; I did not expect to be able to get into ZZZ2 with its 690 foot minimum. I diverted to ZZZ5; which at the time was reporting 300 feet; and has RNAV and ILS minimums of 200 feet.I flew the RNAV XX but at the decision height of 200 feet; on course and on glideslope; I did not break out. I flew the missed approach and shortly after raising my landing gear; the alternator failed. At that point I asked Center for diversion to the nearest airport that was reporting at least 500 foot ceilings. They came back with ZZZ6; which was 42 KM and 20 plus minutes away. I proceeded there.I was in solid IMC and as my battery drained more and more I became more and more concerned. At that point I had not yet declared an emergency. But about half way between ZZZ5 and ZZZ6; my battery became so weak it would no longer drive my autopilot. The backup battery on my EFIS was showing a fairly rapid drop through 40%; so I became especially concerned. At that time; I advised ATC.I was able to successfully fly the RNAV XY; which had minimums of 400 feet and I broke right about at the decision height. I landed without incident. I couldn't find a phone number for Center; so phoned TRACON; who told me they would relay my cancellation to Center.
Bellanca Super Viking pilot reported that a generator failure in IMC resulted in a diversion.