Narrative:

We were originally on bdf arrival but ZAU cleared us direct ord to cross 45 DME at 11000 ft. Passing approximately 13000 ft in the descent at approximately 55 DME, ZAU told us to turn 15 degrees left for traffic. Nearly simultaneously we received a TCASII RA and climbed back up to 14400 ft with the climbing traffic passing 600 ft below us. We never saw the traffic. We then continued our descent but missed the 11000 ft crossing restr at 45 DME. We queried the controller who said the traffic was a twin otter jump plane who was scheduled to drop parachutists. The twin otter was VFR and not talking to center. A phone call to the ZAU shift supervisor after landing at ord confirmed this.

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Original NASA ASRS Text

Title: MD80 AND DH6 HAD CONFLICT IN CLASS E AIRSPACE. AFTER FOLLOWING A TCASII CLB THE CREW WAS UNABLE TO MAKE A PREVIOUSLY ISSUED XING RESTR.

Narrative: WE WERE ORIGINALLY ON BDF ARR BUT ZAU CLRED US DIRECT ORD TO CROSS 45 DME AT 11000 FT. PASSING APPROX 13000 FT IN THE DSCNT AT APPROX 55 DME, ZAU TOLD US TO TURN 15 DEGS L FOR TFC. NEARLY SIMULTANEOUSLY WE RECEIVED A TCASII RA AND CLBED BACK UP TO 14400 FT WITH THE CLBING TFC PASSING 600 FT BELOW US. WE NEVER SAW THE TFC. WE THEN CONTINUED OUR DSCNT BUT MISSED THE 11000 FT XING RESTR AT 45 DME. WE QUERIED THE CTLR WHO SAID THE TFC WAS A TWIN OTTER JUMP PLANE WHO WAS SCHEDULED TO DROP PARACHUTISTS. THE TWIN OTTER WAS VFR AND NOT TALKING TO CTR. A PHONE CALL TO THE ZAU SHIFT SUPVR AFTER LNDG AT ORD CONFIRMED THIS.

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.