Narrative:

Center gave us a descent to 11000 ft; and told us to contact quad cities approach. On calling approach; we were given direct to the 'otten' intersection; and to expect the visual approach to runway 27. We were set up for the visual to runway 31 (ATIS was calling visual runways 27 and 31). There was then some confusion as to where otten was because we were set up for runway 31. We then set up the visual to runway 27; and headed direct to otten. In the confusion; I thought I had heard that we were cleared for the approach to runway 27; so I continued our descent through 11000 ft. I started to think it was odd that we were cleared for the visual without calling the field in sight. Right when I was asking my first officer to clarify that; approach asked us to confirm our assigned altitude (we were through 10000 ft). We replied that we were cleared for the approach; to which he emphatically answered 'I said no such thing.' he then cleared us to 10000 ft. The lowest we descended to was 9700 ft. We then leveled off at 10000 ft. This could have been prevented by clarifying the clearance if we weren't absolutely sure about it.

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Original NASA ASRS Text

Title: AN ACR GIVEN AN INITIAL CLRNC TO MLI RWY 31; WAS ADVISED AFTER BEGINNING THE VISUAL THAT THEY HAD BEEN CLEARED TO 10000 FT AND A VISUAL RWY 27.

Narrative: CTR GAVE US A DSCNT TO 11000 FT; AND TOLD US TO CONTACT QUAD CITIES APCH. ON CALLING APCH; WE WERE GIVEN DIRECT TO THE 'OTTEN' INTXN; AND TO EXPECT THE VISUAL APCH TO RWY 27. WE WERE SET UP FOR THE VISUAL TO RWY 31 (ATIS WAS CALLING VISUAL RWYS 27 AND 31). THERE WAS THEN SOME CONFUSION AS TO WHERE OTTEN WAS BECAUSE WE WERE SET UP FOR RWY 31. WE THEN SET UP THE VISUAL TO RWY 27; AND HEADED DIRECT TO OTTEN. IN THE CONFUSION; I THOUGHT I HAD HEARD THAT WE WERE CLRED FOR THE APCH TO RWY 27; SO I CONTINUED OUR DSCNT THROUGH 11000 FT. I STARTED TO THINK IT WAS ODD THAT WE WERE CLRED FOR THE VISUAL WITHOUT CALLING THE FIELD IN SIGHT. RIGHT WHEN I WAS ASKING MY FO TO CLARIFY THAT; APCH ASKED US TO CONFIRM OUR ASSIGNED ALT (WE WERE THROUGH 10000 FT). WE REPLIED THAT WE WERE CLRED FOR THE APCH; TO WHICH HE EMPHATICALLY ANSWERED 'I SAID NO SUCH THING.' HE THEN CLRED US TO 10000 FT. THE LOWEST WE DSNDED TO WAS 9700 FT. WE THEN LEVELED OFF AT 10000 FT. THIS COULD HAVE BEEN PREVENTED BY CLARIFYING THE CLRNC IF WE WEREN'T ABSOLUTELY SURE ABOUT IT.

Data retrieved from NASA's ASRS site as of May 2009 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.