Narrative:

ATIS at dpa was reporting runways 10, 15 and 2L in use. Approach put us on vectors for localizer runway 10 approach, GS was OTS. We were then cleared for the approach, told to maintain 2600 ft until established. Approach called us for a TA and we told them we were IMC. A second TA was given, we reported still IMC. Approach then told us to contact tower. We crossed the final approach fix and began our descent. We attempted 2 initial calls to tower with no response. At this point we received an RA on our TCASII and responded by leveling off at 1800 ft MSL, we had broken out of the clouds at approximately 2200 ft MSL. We then came within 200 ft of subject traffic. On our third call tower informed us to turn left and after right base for runway 20, then called back and asked if we could still make runway 10. We said no as we were too high and had begun our left turn to enter right base for runway 20. We were never given any course changes to avoid traffic by either approach control or dpa tower. Once on the ground, contact was made with tower operator via land line. He informed me that 1) I should have been cleared for localizer runway 10 circle to land runway 20, 2) the tower was understaffed, only 2 controllers in the tower, 3) ZAU was on the land line and he could not hear us making our radio calls. I told him that I was cleared for a straight-in localizer runway 10 approach and, even if I was cleared for the circle to land, I never reached my minimum descent altitude and he allowed this other aircraft into my controled airspace.

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Original NASA ASRS Text

Title: C560 FLT CREW EXPERIENCED TCASII RA DURING CIRCLE TO LAND AT DPA.

Narrative: ATIS AT DPA WAS RPTING RWYS 10, 15 AND 2L IN USE. APCH PUT US ON VECTORS FOR LOC RWY 10 APCH, GS WAS OTS. WE WERE THEN CLRED FOR THE APCH, TOLD TO MAINTAIN 2600 FT UNTIL ESTABLISHED. APCH CALLED US FOR A TA AND WE TOLD THEM WE WERE IMC. A SECOND TA WAS GIVEN, WE RPTED STILL IMC. APCH THEN TOLD US TO CONTACT TWR. WE CROSSED THE FINAL APCH FIX AND BEGAN OUR DSCNT. WE ATTEMPTED 2 INITIAL CALLS TO TWR WITH NO RESPONSE. AT THIS POINT WE RECEIVED AN RA ON OUR TCASII AND RESPONDED BY LEVELING OFF AT 1800 FT MSL, WE HAD BROKEN OUT OF THE CLOUDS AT APPROX 2200 FT MSL. WE THEN CAME WITHIN 200 FT OF SUBJECT TFC. ON OUR THIRD CALL TWR INFORMED US TO TURN L AND AFTER R BASE FOR RWY 20, THEN CALLED BACK AND ASKED IF WE COULD STILL MAKE RWY 10. WE SAID NO AS WE WERE TOO HIGH AND HAD BEGUN OUR L TURN TO ENTER R BASE FOR RWY 20. WE WERE NEVER GIVEN ANY COURSE CHANGES TO AVOID TFC BY EITHER APCH CTL OR DPA TWR. ONCE ON THE GND, CONTACT WAS MADE WITH TWR OPERATOR VIA LAND LINE. HE INFORMED ME THAT 1) I SHOULD HAVE BEEN CLRED FOR LOC RWY 10 CIRCLE TO LAND RWY 20, 2) THE TWR WAS UNDERSTAFFED, ONLY 2 CTLRS IN THE TWR, 3) ZAU WAS ON THE LAND LINE AND HE COULD NOT HEAR US MAKING OUR RADIO CALLS. I TOLD HIM THAT I WAS CLRED FOR A STRAIGHT-IN LOC RWY 10 APCH AND, EVEN IF I WAS CLRED FOR THE CIRCLE TO LAND, I NEVER REACHED MY MINIMUM DSCNT ALT AND HE ALLOWED THIS OTHER ACFT INTO MY CTLED AIRSPACE.

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.