Narrative:

Small transport X departed meigs field wbound and climbed to 6000', waiting for inbound traffic to ord to pass so that he could resume climb. One inbound passed overhead (nwbound at 7000'). I didn't see the next inbound at 8000'. I instructed small transport X to climb to 14000'. The pilot saw an medium large transport at 8000' and stopped at 7000' until the aircraft passed. Then small transport X resumed climb. This is a good example of 'looking outside the airplane' when VMC and caught someone else's mistake. No matter how well the information is displayed on the radar scope, it still comes down to see and avoid, on the part of both the pilot and controller.

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Original NASA ASRS Text

Title: SMT X WAS ISSUED A CLIMB THROUGH AN OCCUPIED ALT, BUT LEVELED OFF WHEN TRAFFIC WAS SIGHTED.

Narrative: SMT X DEPARTED MEIGS FIELD WBOUND AND CLBED TO 6000', WAITING FOR INBND TFC TO ORD TO PASS SO THAT HE COULD RESUME CLB. ONE INBND PASSED OVERHEAD (NWBOUND AT 7000'). I DIDN'T SEE THE NEXT INBND AT 8000'. I INSTRUCTED SMT X TO CLB TO 14000'. THE PLT SAW AN MLG AT 8000' AND STOPPED AT 7000' UNTIL THE ACFT PASSED. THEN SMT X RESUMED CLB. THIS IS A GOOD EXAMPLE OF 'LOOKING OUTSIDE THE AIRPLANE' WHEN VMC AND CAUGHT SOMEONE ELSE'S MISTAKE. NO MATTER HOW WELL THE INFO IS DISPLAYED ON THE RADAR SCOPE, IT STILL COMES DOWN TO SEE AND AVOID, ON THE PART OF BOTH THE PLT AND CTLR.

Data retrieved from NASA's ASRS site as of August 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.