Narrative:

We were on the bdf arrival into ord. During descent, the controller assigned us a 090 degree heading, off the arrival, and descent to 11000 ft for spacing. After beginning descent from 14000 ft, the controller advised 'skydiving traffic 12 O'clock position.' he did not advise of altitude or distance. A couple of mins later, I picked up the traffic -- 12 O'clock position and 1 - 1 1/2 mi, slightly below. At the same time, the captain saw the traffic, we received TCASII advisory, and then ATC told us 'level off.' he asked if we had the traffic and advised us to maintain our altitude. We then told him we had the traffic. The traffic passed right to left (the other plane was in a turn). We cleared the traffic. He passed to our left and continued into ord. It appears that if we had not had a visual on the traffic, there could have been a problem as the controller failed to report altitude or distance in the beginning. He did not acknowledge the situation once we were clear of the traffic. A few mins later, we changed frequencys to chicago approach. Supplemental information from acn 620513: about this time, we acquired the bogey visually moving left to right and just below us. At this time, we got an RA telling us to climb. Estimate bogey was 1/2 - 1 mi away at closest point.

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Original NASA ASRS Text

Title: POTENTIAL CONFLICT AVOIDED WHEN RADAR CTLR POINTS OUT CONFLICTING SKYDIVING ACFT SLIGHTLY BELOW RPTR'S MD80 DSNDING THROUGH 13000 FT AT BENKY INTXN, IL.

Narrative: WE WERE ON THE BDF ARR INTO ORD. DURING DSCNT, THE CTLR ASSIGNED US A 090 DEG HDG, OFF THE ARR, AND DSCNT TO 11000 FT FOR SPACING. AFTER BEGINNING DSCNT FROM 14000 FT, THE CTLR ADVISED 'SKYDIVING TFC 12 O'CLOCK POS.' HE DID NOT ADVISE OF ALT OR DISTANCE. A COUPLE OF MINS LATER, I PICKED UP THE TFC -- 12 O'CLOCK POS AND 1 - 1 1/2 MI, SLIGHTLY BELOW. AT THE SAME TIME, THE CAPT SAW THE TFC, WE RECEIVED TCASII ADVISORY, AND THEN ATC TOLD US 'LEVEL OFF.' HE ASKED IF WE HAD THE TFC AND ADVISED US TO MAINTAIN OUR ALT. WE THEN TOLD HIM WE HAD THE TFC. THE TFC PASSED R TO L (THE OTHER PLANE WAS IN A TURN). WE CLRED THE TFC. HE PASSED TO OUR L AND CONTINUED INTO ORD. IT APPEARS THAT IF WE HAD NOT HAD A VISUAL ON THE TFC, THERE COULD HAVE BEEN A PROB AS THE CTLR FAILED TO RPT ALT OR DISTANCE IN THE BEGINNING. HE DID NOT ACKNOWLEDGE THE SIT ONCE WE WERE CLR OF THE TFC. A FEW MINS LATER, WE CHANGED FREQS TO CHICAGO APCH. SUPPLEMENTAL INFO FROM ACN 620513: ABOUT THIS TIME, WE ACQUIRED THE BOGEY VISUALLY MOVING L TO R AND JUST BELOW US. AT THIS TIME, WE GOT AN RA TELLING US TO CLB. ESTIMATE BOGEY WAS 1/2 - 1 MI AWAY AT CLOSEST POINT.

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.