Pilots of two aircraft reported they each had an NMAC with a Bonanza that cut them off in the traffic pattern.
Synopsis
Pilots of two aircraft reported they each had an NMAC with a Bonanza that cut them off in the traffic pattern.
Narrative
During a lesson with a commercial student; we were in the traffic pattern (left downwind XX) at ZZZ with four other aircraft. A Cessna (Aircraft Y) was ahead of us (we were in Diamond Aircraft X) when a Bonanza (Aircraft Z) entered the pattern on a left base within a couple hundred ft. of the Cessna; completely cutting them off - to the point that they had to deviate around them. The first call Aircraft Z made was left base for [Runway] XX (after the first close call); and at the time there was an additional Cessna shooting an approach on a 3 mile final. The final traffic announced where they were again and the Bonanza executed a missed approach into the upwind; and rejoined the pattern. By the time both the Cessna traffic landed we were on a 1.5 mile final having reported base and final on CTAF. The Bonanza traffic was making minimal radio calls; and when they called left base XX I saw that they were coming right at us looking at traffic map (0 ft. difference in altitude and all I could tell was that they were within .25 miles horizontally). I immediately took controls from my student; added full power and executed a climbing steep turn to the right. When I finally saw the aircraft; they were passing under us around 300 ft. away. They were on collision course and would have been in our flight path had I not taken evasive action. I asked the Bonanza traffic if they had us in sight and they did not until we were parallel and in the upwind. After re-entering the pattern and landing I obtained their tail number.In the matter of 10 minutes this pilot managed to cut off three different aircraft (all of which had flight instructors present) with possibly two near mid-air collisions. This pilot seriously lacks situational awareness. He also entered the pattern improperly - especially with it being busy; and did not make a sufficient amount of radio calls.
Second reporter narrative
When on a training flight with an Instructor we were on a downwind approach that was slightly extended from our usual. (Due to the increased number of airplanes (5) that were in the area) While in command and waiting for a descent time to turn left base my instructor received a proximity warning through his ipad which was validated with a quick visual inspection. He promptly took the flight controls and exercised a avoidance maneuver to extend the distance between the two aircraft. While I am confident that if both aircraft trajectories were maintained a collision would not have occurred the encounter was so close that a slight deviation in either aircraft trajectories would have resulted in a catastrophic event. The operator of the other aircraft had entered in a abnormal fashion; best described as; Assuming that my frame of reference as 0 degrees from a top down perspective (In line with my aircraft); the pilot in question entered at ~60 degrees to the right at about 100 ft. below us flying level. While my memory of the closest part of the encounter is at best blurry; It was still apparent to me and my Instructor that this encounter was unreasonable. This event was soon followed with two other close encounters with aircraft in the area; my Instructor and another pilot tried to make radio contact asking if the pilot was doing ok; in which they responded with an short apology.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.