Narrative:

It started with LC1; LC2; LA1 and LA2 all combined to me do to staffing. Traffic began to build and very quickly it became heavy traffic. I had 4 VFR aircraft in the traffic pattern 20L and IFR arrivals and departures on 20R. Aircraft X called inbound from the east. When aircraft X got close to the airport I had no way to get him into the ramp safely so I told him to hold in 360s east of the airport. The controller in charge was able to get LC2 split and the controller in charge moved and worked my assist. Once the positions were split I switched the pattern aircraft to LC2 but aircraft X was still on the LC1 frequency. I brought the helicopter over midfield and told him to approach the ramp from the west. This was to avoid the LC2 traffic pattern which was now 4 in pattern with a few arrival/departures aircraft. After the helicopter had crossed he made a hard left turn and crossed just of the end of runway 20L to land at a different ramp. I questioned the pilot who said oh sorry; he was confused which one was correct; but then turned north into aircraft Y just lifting off 20L after his touch and go. Aircraft Y was forced to make a hard left turn only feet off the runway. If I was the pilot I would have said it was an near midair collision. In all my years of ATC this was one of that closest I have seen two aircraft. I likely should have double checked the pilot knew which FBO he wanted but he sounded confident. After traffic died down I discussed this with the controller in charge and other controllers and they all indicated my instructions were clear and it was a good plan. Even still; we have been working 6 day work weeks almost all year and have been feeling run-down and burned out. I can't help but think maybe I missed a clue that the pilot wasn't going to do what I wanted.

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Original NASA ASRS Text

Title: An SNA Controller reports of working a combined position with a helicopter that requested landing at a specific FBO. The position gets split and the Controller keeps the aircraft that is now in another controller's area. The Controller clears aircraft to go where they requested and has what he describes as a NMAC with a departure that the other Local was working.

Narrative: It started with LC1; LC2; LA1 and LA2 all combined to me do to staffing. Traffic began to build and very quickly it became heavy traffic. I had 4 VFR aircraft in the traffic pattern 20L and IFR arrivals and departures on 20R. Aircraft X called inbound from the east. When Aircraft X got close to the airport I had no way to get him into the ramp safely so I told him to hold in 360s east of the airport. The CIC was able to get LC2 split and the CIC moved and worked my assist. Once the positions were split I switched the pattern aircraft to LC2 but Aircraft X was still on the LC1 frequency. I brought the helicopter over midfield and told him to approach the ramp from the west. This was to avoid the LC2 traffic pattern which was now 4 in pattern with a few arrival/departures aircraft. After the helicopter had crossed he made a hard left turn and crossed just of the end of runway 20L to land at a different ramp. I questioned the pilot who said oh sorry; he was confused which one was correct; but then turned north into Aircraft Y just lifting off 20L after his touch and go. Aircraft Y was forced to make a hard left turn only feet off the runway. If I was the pilot I would have said it was an NMAC. In all my years of ATC this was one of that closest I have seen two aircraft. I likely should have double checked the pilot knew which FBO he wanted but he sounded confident. After traffic died down I discussed this with the CIC and other controllers and they all indicated my instructions were clear and it was a good plan. Even still; we have been working 6 day work weeks almost all year and have been feeling run-down and burned out. I can't help but think maybe I missed a clue that the pilot wasn't going to do what I wanted.

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.