Narrative:

I was working the local control position; conducting training. The trainee cleared aircraft X for takeoff to fly straight out. Aircraft Y was upwind north pattern; requesting short approach. The trainee extended their upwind; gave aircraft X a right turn to the north (towards aircraft Y). I was watching the situation; saw they were going to get close; and called aircraft Y to tell them about aircraft X passing off their nose; left to right. Aircraft Y acknowledged; and said that was a near midair collision for them.

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Original NASA ASRS Text

Title: A Local Controller Trainee cleared an aircraft for takeoff and issued a right turn towards a helicopter in the pattern upwind.

Narrative: I was working the local control position; conducting training. The trainee cleared Aircraft X for takeoff to fly straight out. Aircraft Y was upwind north pattern; requesting short approach. The trainee extended their upwind; gave Aircraft X a right turn to the north (towards Aircraft Y). I was watching the situation; saw they were going to get close; and called aircraft Y to tell them about Aircraft X passing off their nose; left to right. Aircraft Y acknowledged; and said that was a NMAC for them.

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.