Narrative:

There was another aircraft on frequency with a similar callsign. ATC tried to contact me in order to stop climbing due to intersecting traffic descending for the left downwind. I had just taken off and did a southerly turnout. ATC did use my full call sign and north number. However; I missed that transmission and aircraft Y responded instead. ATC thought it was me and didn't repeat the transmission. Shortly after; my passenger in the front right seat pointed out the aircraft. And I immediately stopped my climb and began a rapid descent. I am fairly certain that if she hadn't pointed that aircraft out; we would have flown right into it. I had heavily emphasized sterile cockpit rules and scanning for traffic during their passenger brief; and as first time general aviation passengers; they put effort into looking for traffic with me.

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Original NASA ASRS Text

Title: A General Aviation pilot reported a NMAC due to communication issues with similar sounding call signs.

Narrative: There was another aircraft on frequency with a similar callsign. ATC tried to contact me in order to stop climbing due to intersecting traffic descending for the left downwind. I had just taken off and did a southerly turnout. ATC did use my full call sign and N number. However; I missed that transmission and Aircraft Y responded instead. ATC thought it was me and didn't repeat the transmission. Shortly after; my passenger in the front right seat pointed out the aircraft. And I immediately stopped my climb and began a rapid descent. I am fairly certain that if she hadn't pointed that aircraft out; we would have flown right into it. I had heavily emphasized sterile cockpit rules and scanning for traffic during their passenger brief; and as first time General Aviation passengers; they put effort into looking for traffic with me.

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.