Date: 202109
Local time of day: 0601-1200
Location: ZZZ.Tower, US
Flight conditions: VMC
Weather elements / visibility: 10
Light: Daylight
Aircraft: Small Aircraft; Low Wing; 1 Eng; Retractable Gear
Operator: Personal
Operating under: Part 91
Flight plan: None
Mission: Training
Flight phase: Landing
Airspace: Class D ZZZ
ATC / advisory: Tower ZZZ
Second aircraft: Any Unknown or Unlisted Aircraft Manufacturer
Reporter organization: Personal
Reporter function: Instructor; Pilot Not Flying
Reporter qualification: Flight Crew Instrument; Flight Crew Private
Human factors: Workload; Time Pressure; Situational Awareness; Human-Machine Interface; Confusion; Communication Breakdown; Troubleshooting
Second reporter function: Pilot Flying; Trainee; Student
Anomaly: ATC Issue All Types; Conflict NMAC; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Air Traffic Control; Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued Advisory / Alert; Flight Crew Took Evasive Action
Contributing factors: Human Factors
Primary problem: Human Factors

Narrative: During a training flight to become familiarized and train towards a complex endorsement my instructor and I were conducting circuits in the pattern at the airport. The aircraft was unusually busy with 4-5 aircraft in the pattern and ATC was also handling various IFR clearances.We were on our first downwind leg and the ATC told us to extender our downwind a bit for traffic. We read back the instruction and continued on downwind. At the point in the pattern where we usually turn base; ATC told us '[Aircraft X] you are now past traffic in opposite direction; make left traffic pattern at your discretion'. I read back the instruction and me and my instructor took that to mean that we could start our left base turn. We checked to visually make sure final was clear. However; unknown to us there was another aircraft 2 miles to the north on a right base leg that started to turn final. About 10 seconds after turning left [my EFB] gave me a traffic alert and I saw I was too close to the other incoming traffic. I did a steep left 180 to avoid coming into the others aircraft path. Tower also notified us of the traffic alert and also asked us why we were not on downwind. At that point my instructor took over the radios and told ATC the other aircraft was in sight and we were returning to our downwind leg.After we landed we came to the conclusion that ATC miss-spoke and that the call to 'make left traffic pattern at your discretion' was meant for a different aircraft.


Second narrative: During a training flight to obtain familiarization with complex aircraft I was flying with my instructor and we were flying in the pattern. The airport was unusually busy with 4-5 other airplanes in the pattern and various aircraft requesting IFR clearances on the ground.On our first circuit as we were flying downwind; tower told us to stay on downwind leg and we maintained our downwind heading. About the point in the pattern where we usually turn base ATC called and told us '[Aircraft X] you are now past traffic in opposite direction; make left traffic pattern at your discretion'. I read the instruction back and me and my instructor took that to mean we could start our base turn left since final looked clear. However; unknown to us there was an aircraft turning from base (opposite direction) to final about 2 miles north of us. About 10 seconds after we turned base; [the EFB] gave me a traffic alert and i saw that we were too close to the other aircraft after which I started a steep left 180 to avoid traffic. Tower also immediately gave us the alert and asked us why we were not still on downwind.After analyzing the flight; we came to the conclusion that ATC said the wrong call-sign and that the 'make left traffic pattern at your discretion' call was meant for a different aircraft.


Synopsis: Flight Instructor and Trainee reported a NMAC while in the traffic pattern. The pilots believed the radio call; from ATC; to begin their base leg was for them. The Instructor and Trainee took evasive action when another aircraft came into view. Later; the pilots realized the transmission was for another aircraft.