PC-12
Flight Crew Air Transport Pilot (ATP)
Conflict NMAC
Flight Crew Took Evasive Action
Human Factors
Cleared to land Runway 34R by Tower. While on short final Captain (pilot not flying) noticed Mooney aircraft; who was cleared by the Tower to land on Runway 34L; drift quickly into and above our flight path for Runway 34R. There was no communication from the Tower or from the PIC of the Mooney aircraft; and within seconds the Mooney aircraft came within 100 FT (estimated) or less above our aircraft and continuing his descent for the wrong runway. The Captain (pilot not flying) communicated this to the First Officer (pilot flying); and the First Officer (pilot flying) immediately initiated a go-around to the left to avoid collision with the Mooney aircraft. The Captain (pilot not flying) communicated the go-around decision to the Tower; who then eventually cleared us back for left base traffic for Runway 34R. A second attempt for landing was accomplished without incident.There was no communications from the Mooney PIC to anyone about whatever the reason was he/she drifted away from their assigned runway and into ours. Keep a sharp scan even at Towered airports; and especially those with parallel runways. The Tower communicated to us that the Mooney was in the complete wrong and a Tower Supervisor was investigating the incident.
Near mid-air collision by two single engine aircraft on parallel approaches.