Narrative:

On arrival in atl area, approach control told us to expect an ILS to runway 9R, instead of the normal 8L ILS. Somewhat past the OM (burny) on downwind, approach control gave us a turn to 360 degrees and descent to 2700'. He also requested an airspeed of 160 KTS. After a short time on the new heading at 160 KTS, the controller instructed us to turn right to 070 degrees, maintain 3500', 210 KTS to the OM, and cleared for the 9R ILS. The contradiction in altitude and airspeed caused my copilot to hesitate in responding to the instructions and arming the ILS. I told him to start the turn, and immediately asked the controller to confirm his instructions. As he did so, I armed the ILS. We leveled off at 3500' and increased airspeed to 210 KTS. My copilot's initial rate of turn and the late arming of the ILS allowed us to fly through the localizer. The controller alerted us that we were north of the localizer and over another aircraft. He reiterated for us to maintain 3500', 210 KTS, and gave us a heading to return to localizer and cleared us for the approach. When he cleared us to the tower, he thanked us for our help. Other than our initial slow turn to final, late arming of the ILS and conflicting airspeed & altitude assignments, I'm not sure what happened. Our aircraft did not deviate very far north of the localizer. Perhaps an aircraft on an 8L ILS had been cleared to 2800' and had also overshot his localizer, causing both aircraft to approach one another. Our controller could have been reacting to the overshoot of the other aircraft with no time to immediately explain to us. On the ground, tried to call approach, but could not obtain phone #.

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Original NASA ASRS Text

Title: ACR MLG TRACK DEVIATION DURING RADAR VECTORS FOR ILS APCH.

Narrative: ON ARR IN ATL AREA, APCH CTL TOLD US TO EXPECT AN ILS TO RWY 9R, INSTEAD OF THE NORMAL 8L ILS. SOMEWHAT PAST THE OM (BURNY) ON DOWNWIND, APCH CTL GAVE US A TURN TO 360 DEGS AND DSCNT TO 2700'. HE ALSO REQUESTED AN AIRSPD OF 160 KTS. AFTER A SHORT TIME ON THE NEW HDG AT 160 KTS, THE CTLR INSTRUCTED US TO TURN RIGHT TO 070 DEGS, MAINTAIN 3500', 210 KTS TO THE OM, AND CLRED FOR THE 9R ILS. THE CONTRADICTION IN ALT AND AIRSPD CAUSED MY COPLT TO HESITATE IN RESPONDING TO THE INSTRUCTIONS AND ARMING THE ILS. I TOLD HIM TO START THE TURN, AND IMMEDIATELY ASKED THE CTLR TO CONFIRM HIS INSTRUCTIONS. AS HE DID SO, I ARMED THE ILS. WE LEVELED OFF AT 3500' AND INCREASED AIRSPD TO 210 KTS. MY COPLT'S INITIAL RATE OF TURN AND THE LATE ARMING OF THE ILS ALLOWED US TO FLY THROUGH THE LOC. THE CTLR ALERTED US THAT WE WERE N OF THE LOC AND OVER ANOTHER ACFT. HE REITERATED FOR US TO MAINTAIN 3500', 210 KTS, AND GAVE US A HDG TO RETURN TO LOC AND CLRED US FOR THE APCH. WHEN HE CLRED US TO THE TWR, HE THANKED US FOR OUR HELP. OTHER THAN OUR INITIAL SLOW TURN TO FINAL, LATE ARMING OF THE ILS AND CONFLICTING AIRSPD & ALT ASSIGNMENTS, I'M NOT SURE WHAT HAPPENED. OUR ACFT DID NOT DEVIATE VERY FAR N OF THE LOC. PERHAPS AN ACFT ON AN 8L ILS HAD BEEN CLRED TO 2800' AND HAD ALSO OVERSHOT HIS LOC, CAUSING BOTH ACFT TO APCH ONE ANOTHER. OUR CTLR COULD HAVE BEEN REACTING TO THE OVERSHOOT OF THE OTHER ACFT WITH NO TIME TO IMMEDIATELY EXPLAIN TO US. ON THE GND, TRIED TO CALL APCH, BUT COULD NOT OBTAIN PHONE #.

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.