Date: 201302
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Flight conditions: IMC
Weather elements / visibility: Snow; Icing
Light: Night
Aircraft: Dash 8-100
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Climb
Airspace: Class B ZZZ
ATC / advisory: TRACON ZZZ
Aircraft component: Electrical Distribution Busbar
Component problem: Failed
Reporter organization: Air Carrier
Reporter function: Pilot Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Workload; Time Pressure; Human-Machine Interface; Communication Breakdown; Situational Awareness
Second reporter function: Pilot Not Flying; First Officer
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Maintenance; Inflight Event / Encounter Weather / Turbulence
Detector: Automation Aircraft Other Automation; Person Flight Crew
When detected: In-flight
Result: Flight Crew Returned To Departure Airport; General Declared Emergency; General Maintenance Action
Contributing factors: Aircraft; Procedure; Weather
Primary problem: Aircraft

Narrative: After deicing; we departed. On climb out at approximately 3;800 feet; the R AC BUS; R TRU; AND R ELEV HORN HEAT caution lights illuminated. Since we had entered icing conditions; my First Officer and I both agreed that we needed to return to the departure rather than continue. We got vectors for the ILS 27 and landed without incident; taxied to the gate and deplaned the passengers. For some reason; a fault occurred on the R AC BUS. Among other things; this caused us to lose the ice protection systems fed by that bus. This in turn necessitated a return to the field because of the weather conditions.Originally; we were supposed to take another aircraft for this flight. Approximately 25 minutes before departure we were advised that we were to pack up our things and swap into another aircraft. I called Dispatch and then Maintenance Control to get more details. Maintenance Control informed me that the aircraft we were going to had experienced 2 AC BUS problems earlier in the day; but that it was corrected and signed off. Even so; I still voiced strong concerns about taking an airplane with a history of AC electrical problems into snow and icing conditions. (It was snowing at the time.) I suggested that the following day would be a much better time to get the plane to that destination; since the snowstorm would be gone by then. I was told that the decision was final; however; and to swap into it. I think in situations like this; when an airplane has a well-documented history of a recurring problem; it would be much wiser (and safer) to wait for better weather to get it to a maintenance base.


Second narrative: They explained they really need the aircraft flown to our next destination; and that they suspected the previous AC electrical problem was due to consistent glycol buildup on the prop assembly brush blocks. We then made our way to the aircraft; completed the preflight consisting of thoroughly reviewing the logbook.


Synopsis: A DHC-8-100 departed in heavy snow and the Right AC Bus failed; so an emergency was declared the flight returned to the departure airport.