Narrative:

On approach control, we were given vectors, through the localizer 31L and back, to intercept for 31L ILS circle to land runway 22L. Once intercepted, approach control stated cleared for runway 1L ILS circle to runway 22L. Contact tower. The tower was extremely busy and our first transmission was blocked. We continued the approach and contacted tower when leaving the localizer to circle. Tower stated cleared to land runway 22L. Abeam the T/D zone on downwind, the captain asked if we were cleared to land. I asked tower to 'confirm cleared to land runway 22L.' tower stated 'cleared to land runway 22L.' the captain made a close approach and when turning base to final I saw an light transport in a steep right bank angle and told the captain to tighten his turn. Immediately after that the light transport pilot asked what happened. He did a good job evading, however, I don't understand why he let it go that far. He had been cleared for an extended downwind and was established straight-in. We cut him off. After talking to the tower later, they said they were training at the time and they would handle the incident within. Both capts agreed. The sky conditions were such that the color 'white' off the light transport made it difficult to see even in a close up steep bank. Looking back, many departures were in line. We believe the light transport was told to extend it's downwind leg. We weren't aware of this because we were on approach frequency then. The tower cleared us to land on runway 22L twice west/O mention of following another aircraft.

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Original NASA ASRS Text

Title: CLOSE PROX ACR-MLG GA-LTT IN TRAFFIC AT MDW.

Narrative: ON APCH CTL, WE WERE GIVEN VECTORS, THROUGH THE LOC 31L AND BACK, TO INTERCEPT FOR 31L ILS CIRCLE TO LAND RWY 22L. ONCE INTERCEPTED, APCH CTL STATED CLRED FOR RWY 1L ILS CIRCLE TO RWY 22L. CONTACT TWR. THE TWR WAS EXTREMELY BUSY AND OUR FIRST XMISSION WAS BLOCKED. WE CONTINUED THE APCH AND CONTACTED TWR WHEN LEAVING THE LOC TO CIRCLE. TWR STATED CLRED TO LAND RWY 22L. ABEAM THE T/D ZONE ON DOWNWIND, THE CAPT ASKED IF WE WERE CLRED TO LAND. I ASKED TWR TO 'CONFIRM CLRED TO LAND RWY 22L.' TWR STATED 'CLRED TO LAND RWY 22L.' THE CAPT MADE A CLOSE APCH AND WHEN TURNING BASE TO FINAL I SAW AN LTT IN A STEEP R BANK ANGLE AND TOLD THE CAPT TO TIGHTEN HIS TURN. IMMEDIATELY AFTER THAT THE LTT PLT ASKED WHAT HAPPENED. HE DID A GOOD JOB EVADING, HOWEVER, I DON'T UNDERSTAND WHY HE LET IT GO THAT FAR. HE HAD BEEN CLRED FOR AN EXTENDED DOWNWIND AND WAS ESTABLISHED STRAIGHT-IN. WE CUT HIM OFF. AFTER TALKING TO THE TWR LATER, THEY SAID THEY WERE TRNING AT THE TIME AND THEY WOULD HANDLE THE INCIDENT WITHIN. BOTH CAPTS AGREED. THE SKY CONDITIONS WERE SUCH THAT THE COLOR 'WHITE' OFF THE LTT MADE IT DIFFICULT TO SEE EVEN IN A CLOSE UP STEEP BANK. LOOKING BACK, MANY DEPS WERE IN LINE. WE BELIEVE THE LTT WAS TOLD TO EXTEND IT'S DOWNWIND LEG. WE WEREN'T AWARE OF THIS BECAUSE WE WERE ON APCH FREQ THEN. THE TWR CLRED US TO LAND ON RWY 22L TWICE W/O MENTION OF FOLLOWING ANOTHER ACFT.

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.