Narrative:

While in the approach control environment in boi, we were proceeding direct to boi VOR at 13000 ft MSL. We received a TCASII TA from aircraft Y and almost simultaneously received a call from approach control. By the nature of the xmissions there seemed to be controller training in progress. At first, instructions were given to turn right (toward traffic) then a second voice countermanded with a left turn. When traffic was first seen on TCASII, it was in a 12:30 O'clock position, 5 mi, 500 ft below us and climbing. Even before approach control started, I initiated a turn to the left. Approach control, after initial call to turn right, changed instruction (2ND controller) to a left turn. The traffic passed on our right side about 2 mi (TCASII) and apparently continued climb through our altitude. When I got on the ground, I called approach control via phone and talked to the supervisor. He confirmed that training had been in progress and that an error had been made by the student issuing a command to turn to the wrong aircraft. Traffic was never spotted visually because of IMC. No RA was issued by TCASII.

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Original NASA ASRS Text

Title: A CTLR INSTRUCTOR COUNTERMANDED RADAR VECTOR INSTRUCTIONS ISSUED BY HIS TRAINEE BTWN A B727 AND ANOTHER UNKNOWN ACFT, WHICH WAS XING AND CLBING IN FRONT OF THE B727. CTLR ACTIONS WERE INSUFFICIENT TO STOP THE SYS ERROR.

Narrative: WHILE IN THE APCH CTL ENVIRONMENT IN BOI, WE WERE PROCEEDING DIRECT TO BOI VOR AT 13000 FT MSL. WE RECEIVED A TCASII TA FROM ACFT Y AND ALMOST SIMULTANEOUSLY RECEIVED A CALL FROM APCH CTL. BY THE NATURE OF THE XMISSIONS THERE SEEMED TO BE CTLR TRAINING IN PROGRESS. AT FIRST, INSTRUCTIONS WERE GIVEN TO TURN R (TOWARD TFC) THEN A SECOND VOICE COUNTERMANDED WITH A L TURN. WHEN TFC WAS FIRST SEEN ON TCASII, IT WAS IN A 12:30 O'CLOCK POS, 5 MI, 500 FT BELOW US AND CLBING. EVEN BEFORE APCH CTL STARTED, I INITIATED A TURN TO THE L. APCH CTL, AFTER INITIAL CALL TO TURN R, CHANGED INSTRUCTION (2ND CTLR) TO A L TURN. THE TFC PASSED ON OUR R SIDE ABOUT 2 MI (TCASII) AND APPARENTLY CONTINUED CLB THROUGH OUR ALT. WHEN I GOT ON THE GND, I CALLED APCH CTL VIA PHONE AND TALKED TO THE SUPVR. HE CONFIRMED THAT TRAINING HAD BEEN IN PROGRESS AND THAT AN ERROR HAD BEEN MADE BY THE STUDENT ISSUING A COMMAND TO TURN TO THE WRONG ACFT. TFC WAS NEVER SPOTTED VISUALLY BECAUSE OF IMC. NO RA WAS ISSUED BY TCASII.

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.