Skyhawk 172/Cutlass 172
Flight Crew Instrument; Flight Crew Private
Flight Crew Last 90 Days 50; Flight Crew Total 175; Flight Crew Type 150
Time Pressure
Aircraft Equipment Problem Critical; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Flight Crew Landed As Precaution
Aircraft
Smoke appeared to be coming from avionics while on downwind. Radio call to Tower was made informing of electrical fire; as well as intentions of taking the runway and that all communications would be lost as avionics would be turned off. Separation with aircraft cleared to land was maintained as Tower had informed me; just prior to the incident; the traffic I would be following was on a 3 mile final. Knowing the incoming traffics location combined with the severity of the [situation] led to my decision to take the runway. No injuries and no property damage occurred.
C172 pilot reported executing an immediate approach and landing following the appearance of smoke from the avionics equipment.