Date: 201901
Local time of day: 1201-1800
Location: CNO.Airport, CA
Flight conditions: VMC
Weather elements / visibility: Haze / Smoke; 4
Light: Daylight
Aircraft: Amateur/Home Built/Experimental
Operator: Personal
Operating under: Part 91
Flight plan: IFR
Mission: Personal
Flight phase: Descent
Airspace: Class C ONT; Class D CNO
ATC / advisory: Tower CNO
Second aircraft: Any Unknown or Unlisted Aircraft Manufacturer
Reporter organization: Personal
Reporter function: Single Pilot
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Flight Instructor; Flight Crew Instrument; Flight Crew Multiengine
Human factors: Situational Awareness; Human-Machine Interface; Confusion; Communication Breakdown
Anomaly: ATC Issue All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Automation Aircraft RA; Person Air Traffic Control; Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Air Traffic Control Issued Advisory / Alert; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Took Evasive Action
Contributing factors: Human Factors; Procedure; Chart Or Publication; Airspace Structure
Primary problem: Airspace Structure

Narrative: A traffic conflict occurred between me and an airplane flying the ILS 26R KCNO at 1600 feet on the boundary of Ontario Class C Surface airspace and KCNO Class D airspace. On initial climb to KCNO; I contacted KONT Tower for clearance through their airspace. I was given beacon code 0222 and told to cross midfield at or below 2500 feet. Approaching KCNO on a right base for Runway 26R; I became concerned that KONT had not handed me off to KCNO Tower. At this exact same time I had to make an aggressive right turn to avoid two large soaring birds (Vultures). I then asked KONT if they wanted me to go over to KCNO Tower to which there was no reply. At this time; my ADS-B displayed a traffic warning at 12 o'clock and 200 feet below me so I executed an immediate climb and scanned for the traffic. I made another call to Ontario regarding the handoff and was told to contact KCNO Tower. I hit the 'flip-flop' switch instantly selecting KCNO Tower only to hear KCNO Tower calling out a traffic alert instructing the conflicting traffic to climb. I never saw the traffic and at this point the ADS-B warning had disappeared. KCNO Tower instantly gave me clearance to land Runway 26R.Upon parking at my destination; I called the KCNO Tower supervisor who asked if I was talking to Ontario. I replied 'yes' and gave him the beacon code 0222 that Ontario assigned me and verified this number by referencing my transponder. The KCNO supervisor told me that Ontario indicated they had not been working my flight. I responded that that was not accurate and relayed the above narrative.I reviewed the AIM 3-2-5a.; LA Sectional airspace boundary detail relative to the ILS 26R KCNO; JO 7110.65 paragraph 2-1-14a; 2-1-15b; 2-1-16 and 2-1-17a; Part 91.129 and 91.130. After this review; I called the Chino Tower supervisor back to resolve the inconsistency regarding Ontario Tower's statement that they were not in contact with me. The Supervisor indicated that KONT had tracked me with beacon code 0220 and not the 0222 code that I had in my transponder. The supervisor speculated that this beacon code discrepancy likely resulted in no call sign associated with the radar target which may explain the delay in responding to my handoff query. He also stated that; via a Letter of Agreement with Ontario; Ontario should have handed me off much further north; over Riverside Ave. The supervisor also indicated that a Letter of Agreement with Ontario was required because of KONT Class C airspace that infringes on the ILS 26R KCNO. The KCNO Tower supervisor indicated that data was being collected showing some aircraft deviating south while flying the ILS 26R to avoid the KONT Class C surface area.The discussion with the KCNO Tower supervisor was informative and productive. This research was for the purpose of finding solutions and not to lay blame. An expedient conclusion may try to fault the controller for a late handoff or the pilot for not being more assertive in obtaining a timely handoff. My review of part 91 operating rules indicates I was in full compliance. Both of these approaches would miss the root cause of this traffic conflict. The location of the KONT Class C airspace boundary.The southern boundary between KONT Class C airspace and the KCNO Class D is located too far south creating a hazard for pilots and unnecessarily increasing the workload on controllers. It is unsafe for a pilot to deviate from the KCNO localizer inside the FAF in order to avoid KONT Class C airspace. A segment of the ILS 26R KCNO actually lies within the KONT class C airspace. A southbound aircraft in KONT Class C airspace will not be prompted to ask for the handoff to KCNO Tower until precariously close to traffic on the ILS 26R KCNO. Since pilots are not privy to Letters of Agreement placing the standard handoff much further north; they would not recognize a failed handoff until much too late. With the boundary relocated further north; both of these hazards will be eliminated.




Synopsis: A pilot on a right base reported a NMAC with another aircraft straight in on an instrument approach.