Date: 201909
Local time of day: 1801-2400
Location: BIS.Tower, ND
Flight conditions: VMC
Weather elements / visibility: 100
Light: Night
Aircraft: SR22
Operator: Personal
Operating under: Part 91
Flight plan: VFR
Mission: Personal
Flight phase: Landing
Airspace: Class D BIS
ATC / advisory: CTAF Y19
Reporter organization: Personal
Reporter function: Single Pilot
Reporter qualification: Flight Crew Instrument; Flight Crew Commercial
Human factors: Communication Breakdown; Situational Awareness; Confusion
Anomaly: Airspace Violation All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Took Evasive Action
Contributing factors: Human Factors; Company Policy; Airspace Structure
Primary problem: Human Factors

Narrative: 30 miles out on my return flight to home based airport; Y19; I heard ONE helicopter announcing on CTAF they were in the pattern on Runway 22. It was night VMC; unlimited ceiling and visibility; winds were 290 at 7kts favoring Runway 31 and grass Runway 22. Company Cessna 210 was 10 miles ahead of me; on the RNAV 31. I announced my intentions over CTAF 25; 15; 10; and 5 miles out. I was inbound from the south/southeast and descending.About 10 miles south of the airport; I noted a helicopter approximately 8 miles west of Y19 at 3;000 ft. MSL. I asked over CTAF if that traffic was approaching Y19. A helicopter replied back that there were three helicopters all flying pattern at Y19. The two others were not announcing or reporting traffic pattern entries or positions on CTAF. I then replied that I saw a helicopter approximately 8 miles west of Y19; left of me at 10'oclock and asked if they would like me to fly west of them as I was planning on entering midfield left downwind for Runway 31. They replied no; they would follow me in. So I announced that I was proceeding towards a midfield entry left downwind for Runway 31.Just after this reply; one of the helicopters responded they were 'hovering over the approach end of Runway 4'. I was 5 miles to the southwest at this time and did not see any helicopter hovering over the approach end; and must have been the helicopter I saw 8 miles west of Y19. I did also see a helicopter at the approach end of Runway 22 on the ground however. I did not see a 3rd helicopter at that time.I entered the left downwind for Runway 31. At this time my company C210 traffic was short final over the numbers for Runway 31. As I turned right; entering the left downwind for Runway 31; I noted a helicopter 2 miles and closing at my 2'oclock on a left base for Runway 31 I assumed; just below my altitude. I asked on CTAF if this helicopter was on base because no traffic had announced being on a left downwind; base; or final for Runway 31. The helicopter responded they were on a left base for Runway 31.I then immediately stopped my descent; initiated a climb and turned to the left while trying to maintain visualization of the aircraft. This put me into the edge of BIS Delta airspace for about 30 seconds. I did not have time to radio BIS Tower nor was it safe for me to switch frequencies during this close encounter. Once I was safely clear of the traffic and collision was avoided; I exited Delta airspace and flew southwest. I announced I'd perform a teardrop turn and follow the helicopter that was now on final into Y19 as I felt this was safest route knowing there was a helicopter on approach end of Runway 22 not announcing; and I wanted to keep all potential traffic in front of my view rather than possibly below my wings in a blind spot. I heard no other CTAF announcements from the other two helicopters at that time.I spoke with my Company traffic C210 once safely on the ground who agreed they did not hear the other 2 pilots either. I feel the problem was caused by pilots not announcing their positions in the pattern or intentions of pattern entry; as well as 3 helicopters using numerous runways while not announcing their positions/intentions. One helicopter was clearly either hovering close to or on the ground approach end of Runway 22 while not announcing; they appeared stationary. However; another helicopter announced they're hovering over the approach end of Runway 4 making it seem they were using Runway 4 and 22 at the same time. Either the helicopter I saw on Runway 22 approach end announced the wrong runway end he was on; OR the helicopter 8 miles west of Y19 I saw on approach was truly the one 'hovering over the approach end of Runway 4'; which if that was the case; 8 miles west of the airport is NOT hovering over the approach end. I feel tighter traffic patterns by this pilot (2-4 miles even) would have made it clear that he was in the pattern and I would have for sure deviated furtherwest before entry into the left downwind of Runway 31.When the helicopter pilot announced that he would follow me in and did not need me to deviate west of him; I continued my approach for entry into the downwind. The next radio call on CTAF that there was a helicopter hovering on the approach end of Runway 4 confused me. I think there should be a safety rule that helicopters cannot 'hover' over the approach end of a crossing runway that is the active downwind leg for another runway. This creates a significant collision risk with traffic entering the downwind for the other active runway. Also; all traffic should report position in the pattern; this would have been helpful. Announcing 'hovering' over the end of a runway does not help other traffic know which direction the aircraft is planning on going.Main factors affecting this situation I think were lack of communication; hovering of helicopters and not knowing which runways they were using or planning to use. In retrospect now; I would have headed straight west (keeping me southwest of Y19); at least 15 miles from the airport; climbed above traffic pattern altitude; and established clear communication with all three helicopters in the pattern to formulate a safe plan of entry into the pattern; ensuring all of us pilots knew the others' intentions.




Synopsis: SR22 pilot reported that three helicopters failed to communicate their positions appropriately on CTAF; causing him to deviate into Class D airspace.