Narrative:

Aircraft X was heading 350 degrees at 4;000 feet at PXR185005; air carrier Y was southbound; VFR at 3;500 feet at PXR270003; air carrier Y was 2 miles in trail of air carrier Z; also southbound and VFR at 3;500 feet. As soon as aircraft X checked onto my frequency I issued traffic; aircraft X responded that he had received an RA and was climbing. Aircraft X stopped the climb at 4;500 feet and descended back to 4;000. No further action taken by pilot. Recommendation; raise the satellite airspace ceiling to 6;000 over phx/pxr - this is an everyday occurrence in this block of airspace; multiple aircraft; both IFR and VFR; transit this area between 3;500 and 5;000 feet.

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Original NASA ASRS Text

Title: P50 controller described a TCAS RA event received by an IFR aircraft at 4000 involving two VFR aircraft at 3500; the reporter suggesting airspace modifications to limit the aircraft utilizing this subject area.

Narrative: Aircraft X was heading 350 degrees at 4;000 feet at PXR185005; Air Carrier Y was Southbound; VFR at 3;500 feet at PXR270003; Air Carrier Y was 2 miles in trail of Air Carrier Z; also southbound and VFR at 3;500 feet. As soon as Aircraft X checked onto my frequency I issued traffic; Aircraft X responded that he had received an RA and was climbing. Aircraft X stopped the climb at 4;500 feet and descended back to 4;000. No further action taken by pilot. Recommendation; raise the satellite airspace ceiling to 6;000 over PHX/PXR - this is an everyday occurrence in this block of airspace; multiple aircraft; both IFR and VFR; transit this area between 3;500 and 5;000 feet.

Data retrieved from NASA's ASRS site as of April 2012 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.