Narrative:

I had just gotten on my first control position. My briefing was basically 2 airplanes; a C172; northbound departure to the northeast practice area; and an inbound IFR hawker jet 12 miles north; not yet on frequency. The first thing I noticed was that the C172 was more northeast departure than north departure and was basically going right up the final approach course. The 2 aircraft were 10 miles apart and converging; one climbing and one descending. I issued traffic to both aircraft and they were looking. I issued again and they were looking again. Finally; the hawker said he was getting a TCAS RA and climbing to avoid. Although we are a VFR tower and the TCAS happened outside of our airspace; I should have turned the C172 west with a suggested heading as soon as I got on frequency; or turned the hawker south when he was 8-10 miles out. The above reported TCAS is too common at sdl. My educated guess is we get at least 50 jets/turboprops a day on the JCOBS2 arrival. The JCOBS2 arrival generally flies right over the northeast practice area. I often wonder how 'practice areas' come to be. I don't see them on charts; they are just there and all the students and instructors know them. The northeast practice area has probably been there longer than sdl has been the major business jet airport for phoenix metro area. In my opinion; one of them needs to be moved. Unfortunately; I believe it is just a matter of time before there is a midair between an aircraft on the JCOBS2 and an aircraft inbound or outbound from the northeast practice area from sdl or dvt.

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Original NASA ASRS Text

Title: SDL Controller described a TCAS RA experienced by an inbound IFR corporate jet on the JCOBS STAR and a VFR departure aircraft. The reporter indicated that this type of event is all too common in the the subject area.

Narrative: I had just gotten on my first control position. My briefing was basically 2 airplanes; a C172; northbound departure to the northeast practice area; and an inbound IFR Hawker jet 12 miles north; not yet on frequency. The first thing I noticed was that the C172 was more northeast departure than north departure and was basically going right up the final approach course. The 2 aircraft were 10 miles apart and converging; one climbing and one descending. I issued traffic to both aircraft and they were looking. I issued again and they were looking again. Finally; the Hawker said he was getting a TCAS RA and climbing to avoid. Although we are a VFR Tower and the TCAS happened outside of our airspace; I should have turned the C172 west with a suggested heading as soon as I got on frequency; or turned the Hawker south when he was 8-10 miles out. The above reported TCAS is too common at SDL. My educated guess is we get at least 50 jets/turboprops a day on the JCOBS2 arrival. The JCOBS2 arrival generally flies right over the northeast practice area. I often wonder how 'practice areas' come to be. I don't see them on charts; they are just there and all the students and instructors know them. The northeast practice area has probably been there longer than SDL has been the major business jet airport for Phoenix metro area. In my opinion; one of them needs to be moved. Unfortunately; I believe it is just a matter of time before there is a midair between an aircraft on the JCOBS2 and an aircraft inbound or outbound from the northeast practice area from SDL or DVT.

Data retrieved from NASA's ASRS site as of July 2013 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.