Narrative:

Being vectored from south (okk 1 arrival) to ord on typically busy morning. Were advised to expect ILS runway 4R (also landing runways 9R and 9L). One aircraft ahead of us was vectored through localizer, and was so advised by ord approach. When we began receiving vectors for runway 4R, we tuned and idented the first officer's navigation to runway 4R localizer. Captain tuned and idented to ord VOR. As we were vectored northbound, approach informed all traffic to use 132.7 for tower, as 120.75 had gone OTS. Our next instructions were to turn right 060 degrees and intercept runway 4R localizer, which we read back. We had assumed that we also had been vectored through localizer runway 4R and were now on intercept heading. At this time, we noticed that based on bearing to ord, we would not intercept runway 4R at all, and also noticed that we had lost signal for runway 4R localizer. We advised approach, who informed us we had been cleared for runway 9R. From here we were vectored north of runway 9R and fit into runway 9R traffic for normal landing. Lesson learned: never assume. Particularly with even minor communication/frequency problems. When given the 060 degree heading without having been told 'vectors through localizer' previously, I should have confirmed the runway with the approach controller.

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Original NASA ASRS Text

Title: ACR FLC EXPERIENCES SOME CONFUSION OVER ASSIGNED RWY AT ORD, AND A TRACK DEV RESULTS.

Narrative: BEING VECTORED FROM S (OKK 1 ARR) TO ORD ON TYPICALLY BUSY MORNING. WERE ADVISED TO EXPECT ILS RWY 4R (ALSO LNDG RWYS 9R AND 9L). ONE ACFT AHEAD OF US WAS VECTORED THROUGH LOC, AND WAS SO ADVISED BY ORD APCH. WHEN WE BEGAN RECEIVING VECTORS FOR RWY 4R, WE TUNED AND IDENTED THE FO'S NAV TO RWY 4R LOC. CAPT TUNED AND IDENTED TO ORD VOR. AS WE WERE VECTORED NBOUND, APCH INFORMED ALL TFC TO USE 132.7 FOR TWR, AS 120.75 HAD GONE OTS. OUR NEXT INSTRUCTIONS WERE TO TURN R 060 DEGS AND INTERCEPT RWY 4R LOC, WHICH WE READ BACK. WE HAD ASSUMED THAT WE ALSO HAD BEEN VECTORED THROUGH LOC RWY 4R AND WERE NOW ON INTERCEPT HEADING. AT THIS TIME, WE NOTICED THAT BASED ON BEARING TO ORD, WE WOULD NOT INTERCEPT RWY 4R AT ALL, AND ALSO NOTICED THAT WE HAD LOST SIGNAL FOR RWY 4R LOC. WE ADVISED APCH, WHO INFORMED US WE HAD BEEN CLRED FOR RWY 9R. FROM HERE WE WERE VECTORED N OF RWY 9R AND FIT INTO RWY 9R TFC FOR NORMAL LNDG. LESSON LEARNED: NEVER ASSUME. PARTICULARLY WITH EVEN MINOR COM/FREQ PROBS. WHEN GIVEN THE 060 DEG HDG WITHOUT HAVING BEEN TOLD 'VECTORS THROUGH LOC' PREVIOUSLY, I SHOULD HAVE CONFIRMED THE RWY WITH THE APCH CTLR.

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.