Date: 201410
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Weather elements / visibility: 10
Light: Daylight
Aircraft: Cessna 150
Operator: Personal
Operating under: Part 91
Flight plan: None
Mission: Personal
Flight phase: Initial Climb
Airspace: Class D ZZZ
ATC / advisory: Tower ZZZ
Second aircraft: Skyhawk 172/Cutlass 172
Reporter organization: Personal
Reporter function: Single Pilot; Pilot Flying
Reporter qualification: Flight Crew Private; Flight Crew Instrument
Human factors: Situational Awareness
Second reporter function: Single Pilot
Anomaly: Conflict NMAC; Deviation - Track / Heading All Types; 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: The event occurred during a Flying Competition. Just before take-off a change was made so that my aircraft would become the third in a heat of four aircraft that would be making circuits in the pattern around the airfield. The original plan was for my aircraft to be number one in a heat of two. Upon reaching the end of Runway XX there were two aircraft from the heat before us waiting for take-off clearance. The four aircraft were notified that the two heats of two aircraft would be combined to one heat of four just before take-off via tower frequency. I did not know of this change until the second of the four aircraft were departing. Realizing I had mis-dialed the Tower frequency; I changed to the proper frequency and realized the change to the number of aircraft in the heat. I quickly acknowledged the change and took Runway XX to depart about 45 seconds behind the aircraft ahead. Aircraft in the pattern were calling mid-field downwind for landing clearance. After my second landing of three I heard what I thought was the aircraft ahead call mid-field downwind as I was crossing the end of runway XX on an upwind. I proceeded to turn crosswind and the tower controller notified me that I had turned ahead of the aircraft that was ahead of me in the heat. I quickly spotted the aircraft about 300 feet above and 200 feet out to my 11 o clock. Keeping the aircraft in sight I turned underneath and proceeded in the pattern in slow flight to increase the separation between our aircraft.


Second narrative: The event took place during a Flying Competition. The competition heat my aircraft was positioned in was merged with the following heat due to lack of aircraft in both heats. Our heat was cleared for takeoff; and entered right traffic on Runway XX; with each aircraft keeping visual separation from preceding traffic in the heat for the duration of the competition; which consisted of three passes for power off landings. Upon completion of the first pass; I maintained position of the upwind until the preceding aircraft was off my right wing on the downwind to ensure adequate spacing between us for the following pass. The preceding aircraft called midfield downwind for Runway XX as I began my turn from upwind to crosswind for the same runway. Upon turning onto downwind I observed the aircraft following mine abeam my right wing and about 200 ft below my position; and began to initiate a climb away from the other aircraft. Tower informed both aircraft of our proximity to each other; and as both aircraft verbally communicated that they had visual upon the other I maintained my altitude and continued with the pattern.


Synopsis: C150 pilot reports losing track of the C172 ahead in the traffic pattern and turning crosswind too early resulting in a NMAC. The Tower called out the potential conflict and both pilots took evasive action. The C172 pilot's report is also included.