Narrative:

The following is in reference to a scenario that occurred with aircraft X, a BE40, that was on vector to the ILS runway 26R at 7000 ft at publication airport. Aircraft Z, a VFR D328, was holding over publication VORTAC VFR at 7500 ft. Aircraft Y, a C172, was VFR eastbound from publication at 6400 ft. Aircraft X was flying a heading of 170 degrees, base leg, and issued 'turn right heading 230 degrees, maintain 7000 ft until established on the localizer, cleared ILS runway 26R approach.' at the time the clearance was issued, aircraft Y was approximately 2 mi west of aircraft X position heading east and aircraft Z was approximately 2 mi west holding at 7500 ft VFR. Aircraft X advised TCASII RA reference aircraft Z and advised that he had him in sight. Aircraft X began his descent to 6600 ft prior to turning final then reported that he came close to aircraft Y. I advised aircraft X the cessna was below him at 6400 ft. Aircraft X advised that he would be filing a hatr. It has been our understanding (ATC at publication) that 'established on the localizer' meant that the pilot was on the final approach course and established. If a pilot was given an altitude to maintain until established on the localizer, the pilot will not begin a descent until flying inbound on the final approach course.

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Original NASA ASRS Text

Title: A MIL BE40 AT PUB SEBOUND TO INTERCEPT THE ILS AT 7000 FT RPTED CONFLICTING WITH A C172 VFR AT 6400 FT EBOUND.

Narrative: THE FOLLOWING IS IN REF TO A SCENARIO THAT OCCURRED WITH ACFT X, A BE40, THAT WAS ON VECTOR TO THE ILS RWY 26R AT 7000 FT AT PUB ARPT. ACFT Z, A VFR D328, WAS HOLDING OVER PUB VORTAC VFR AT 7500 FT. ACFT Y, A C172, WAS VFR EBOUND FROM PUB AT 6400 FT. ACFT X WAS FLYING A HDG OF 170 DEGS, BASE LEG, AND ISSUED 'TURN R HDG 230 DEGS, MAINTAIN 7000 FT UNTIL ESTABLISHED ON THE LOC, CLRED ILS RWY 26R APCH.' AT THE TIME THE CLRNC WAS ISSUED, ACFT Y WAS APPROX 2 MI W OF ACFT X POS HDG E AND ACFT Z WAS APPROX 2 MI W HOLDING AT 7500 FT VFR. ACFT X ADVISED TCASII RA REF ACFT Z AND ADVISED THAT HE HAD HIM IN SIGHT. ACFT X BEGAN HIS DSCNT TO 6600 FT PRIOR TO TURNING FINAL THEN RPTED THAT HE CAME CLOSE TO ACFT Y. I ADVISED ACFT X THE CESSNA WAS BELOW HIM AT 6400 FT. ACFT X ADVISED THAT HE WOULD BE FILING A HATR. IT HAS BEEN OUR UNDERSTANDING (ATC AT PUB) THAT 'ESTABLISHED ON THE LOC' MEANT THAT THE PLT WAS ON THE FINAL APCH COURSE AND ESTABLISHED. IF A PLT WAS GIVEN AN ALT TO MAINTAIN UNTIL ESTABLISHED ON THE LOC, THE PLT WILL NOT BEGIN A DSCNT UNTIL FLYING INBOUND ON THE FINAL APCH COURSE.

Data retrieved from NASA's ASRS site as of July 2007 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.