Beechjet 400
Flight Crew Air Transport Pilot (ATP)
Other / Unknown
Conflict NMAC
Flight Crew Executed Go Around / Missed Approach
Human Factors; Airport
At a 2 mile final on a Visual Approach to landing at PPO; I noticed an airplane converging with us on our left.  The traffic was less than 300 feet away horizontally and 30 feet above us. I was already hand flying the airplane; and I made an abrupt maneuver to avoid a collision. After completion of the maneuver; a go around was executed. A normal entry back into the traffic pattern and a normal landing were then accomplished. The aircraft in question was not making radio calls and was not operating with a transponder due to the fact that there were no warnings from the TCAS system.
BE400 First Officer experiences a NMAC with a light aircraft on final approach at PPO and goes around. The light aircraft was not communicating on the CTAF nor did it have a transponder.