Date: 201908
Local time of day: 1201-1800
Location: MKO.Airport, OK
Flight conditions: VMC
Weather elements / visibility: 10
Light: Daylight
Aircraft: Small Aircraft; Low Wing; 2 Eng; Retractable Gear
Operator: FBO
Operating under: Part 91
Flight plan: IFR
Mission: Training
Flight phase: Initial Approach
Airspace: Class E ZFW
ATC / advisory: CTAF MKO; Center ZFW
Second aircraft: Small Transport
Reporter organization: FBO
Reporter function: Pilot Not Flying; Instructor
Reporter qualification: Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Commercial; Flight Crew Flight Instructor
Human factors: Situational Awareness; Communication Breakdown
Anomaly: Conflict NMAC; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew; Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued Advisory / Alert; Flight Crew Took Evasive Action
Contributing factors: Human Factors; Airspace Structure; Procedure; Weather
Primary problem: Human Factors

Narrative: My student and I were on an IFR flight plan to MKO. We received clearance from ATC (Fort Worth Center) to descend to 3;500 ft. MSL from 5;000 ft. MSL and were cleared direct to POKYO for the RNAV RWY 13 into MKO. When we were about 5nm west of POKYO; ATC warned us of an airplane at our 12 o'clock; heading towards us about 5nm away. We looked for the traffic but were unable to see the reported traffic. We were in VMC conditions with broken clouds around us about at our same altitude. Visibility was unlimited. About a minute or two later ATC again warned us of the traffic and when we reported we were unable to see the traffic; ATC instructed us to turn right 40 degrees to avoid the oncoming traffic. Upon initiating the turn; I saw Aircraft Y fly about 300 ft. below us. Once the aircraft passed us and was no longer a factor; we were cleared back direct to POKYO and cleared for the approach. We then executed a hold in lieu of a procedure turn and continued the approach. Once we were about 3 miles from the final approach fix (CULAD); ATC cleared us to change to the advisory frequency and advised us to cancel our IFR flight plan on the ground or with them in the air. We elected to cancel our IFR flight plan in the air with Ft. Worth Center since we were in VMC conditions had visual contact with the airport. Once we switched over to CTAF; our traffic alert system alerted us of traffic at our same altitude and location. We started to look around and I saw Aircraft Y to the West of us; at our same altitude; and about half a mile away initiating a bank away from us. My student announced our location and intentions on CTAF and the pilot of Aircraft Y replied 'We've almost hit you guys twice now and you should be talking on CTAF when you're operating close to an airport.' I replied that we were on an IFR flight plan talking with Ft. Worth Center and they had just switched us over to CTAF. The Aircraft Y pilot then replied that we should be monitoring the CTAF frequency anyway. I thanked the pilot for his advice and for not running into us twice. MKO is class G airspace until 700 ft. AGL and then class E after then.




Synopsis: GA pilot reported an NMAC on approach prior to communications transfer from ARTCC to CTAF.