Narrative:

I was serving as PIC (pilot in command) in the left seat with a CFI in the right seat who was providing differences training for me from SR20 to SR22 aircraft. We had been making repeated closed traffic touch and go's and stop and go's at ZZZ. The tower controller had issued a blanket instruction to make left traffic and to report entering the downwind leg of the pattern each time. We had made perhaps four or five full loops in the pattern and; in this instance; as I rolled from crosswind to left downwind; there was another aircraft on the frequency making an initial call up to tower. It sounded like there was some misunderstanding about the type of that aircraft that cause that pilot and controller to occupy the frequency for most of our downwind leg. Once there was a break in the transmissions; to the best of my recollection; I reported that we were downwind and the tower controller replied by clearing us for the option. We commenced our descent from pattern altitude and shortly thereafter rolled into a base leg and pretty much directly into final. Shortly thereafter; my instructor spotted the other aircraft at approximately our 4 or 5 o'clock position and perhaps a few hundred feet away laterally and slightly below us vertically. Due to the placement of windows in the SR22 and the rapid nature of the situation; my ability to precisely judge the distance between our two aircraft is not very accurate. My instructor immediately took the controls upon spotting the other aircraft and went full power up and away from the other plane. At no point did the traffic alerting system in our aircraft provide any warnings of traffic in the vicinity. The other aircraft continued on their final and landed. They made a radio call to the tower controller to figure out what was going on and the tower controller indicated that he had not cleared us to turn base. Both my instructor and I clearly remembered having been cleared for the option. Furthermore; our audio panel has a record function and; after the fact; we went back through the recorded transmissions and there was a very clear recording of us being cleared for the option shortly before the other aircraft was cleared to land. We were making repeated touch and go's so it is conceivably possible that the recording we were reviewing was from a prior lap in the pattern but it was proceeded by the recording of the other aircraft making their initial call up so that doesn't seem likely. After the near miss and being chastised by the tower controller for ostensibly turning base without a clearance; we departed his airspace and returned to our home airport without incident.

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Original NASA ASRS Text

Title: Pilots from two different single engine aircraft reported a NMAC while on final.

Narrative: I was serving as PIC (Pilot In Command) in the left seat with a CFI in the right seat who was providing differences training for me from SR20 to SR22 aircraft. We had been making repeated closed traffic touch and go's and stop and go's at ZZZ. The tower controller had issued a blanket instruction to make left traffic and to report entering the downwind leg of the pattern each time. We had made perhaps four or five full loops in the pattern and; in this instance; as I rolled from crosswind to left downwind; there was another aircraft on the frequency making an initial call up to tower. It sounded like there was some misunderstanding about the type of that aircraft that cause that pilot and controller to occupy the frequency for most of our downwind leg. Once there was a break in the transmissions; to the best of my recollection; I reported that we were downwind and the tower controller replied by clearing us for the option. We commenced our descent from pattern altitude and shortly thereafter rolled into a base leg and pretty much directly into final. Shortly thereafter; my instructor spotted the other aircraft at approximately our 4 or 5 o'clock position and perhaps a few hundred feet away laterally and slightly below us vertically. Due to the placement of windows in the SR22 and the rapid nature of the situation; my ability to precisely judge the distance between our two aircraft is not very accurate. My instructor immediately took the controls upon spotting the other aircraft and went full power up and away from the other plane. At no point did the traffic alerting system in our aircraft provide any warnings of traffic in the vicinity. The other aircraft continued on their final and landed. They made a radio call to the tower controller to figure out what was going on and the tower controller indicated that he had not cleared us to turn base. Both my instructor and I clearly remembered having been cleared for the option. Furthermore; our audio panel has a record function and; after the fact; we went back through the recorded transmissions and there was a very clear recording of us being cleared for the option shortly before the other aircraft was cleared to land. We were making repeated touch and go's so it is conceivably possible that the recording we were reviewing was from a prior lap in the pattern but it was proceeded by the recording of the other aircraft making their initial call up so that doesn't seem likely. After the near miss and being chastised by the tower controller for ostensibly turning base without a clearance; we departed his airspace and returned to our home airport without incident.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.