Narrative:

[I was] working [runway] 22R approach at C90. Triple runways were in use and traffic from southwest the plano sector was rerouted to the right downwind for 22R. Runway 22L was opened and being used as a trip runway and visual approaches to that runway were in use because the localizer was OTS. Thunderstorms had just passed thru and high winds aloft from the west were a factor. We were using the new fusion radar and it was taking some getting used to. The timing of turns is different as is the movement of the targets. I turned base leg from the right downwind behind a heavy airbus with what I thought was an A320 and was a little early from the west side. Turned in behind the heavy and was being pushed by the wind. Turned in to final and was gaining on the heavy. Tried to obtain visual on the heavy but a scud layer had moved in. [I] vectored the A320 off to the right to avoid loss of separation. Obtained visual on the airport with the A320 and vectored him back in towards the airport. The timing with the new fusion radar and the wind played a roll in the use of the maneuvering to maintain separation behind the heavy. More experience with the new fusion radar will help with the timing when vectoring to the finals. Many controllers have been late on turns because of the pace at which this radar moves and what we've been used to with the old ASR 9.

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Original NASA ASRS Text

Title: C90 Controller experienced a loss of separation event claiming the new 'fusion' RADAR.

Narrative: [I was] working [Runway] 22R approach at C90. Triple runways were in use and traffic from southwest the Plano Sector was rerouted to the right downwind for 22R. Runway 22L was opened and being used as a trip runway and visual approaches to that runway were in use because the localizer was OTS. Thunderstorms had just passed thru and high winds aloft from the west were a factor. We were using the new fusion RADAR and it was taking some getting used to. The timing of turns is different as is the movement of the targets. I turned base leg from the right downwind behind a heavy Airbus with what I thought was an A320 and was a little early from the west side. Turned in behind the heavy and was being pushed by the wind. Turned in to final and was gaining on the heavy. Tried to obtain visual on the heavy but a scud layer had moved in. [I] vectored the A320 off to the right to avoid loss of separation. Obtained visual on the airport with the A320 and vectored him back in towards the airport. The timing with the new fusion RADAR and the wind played a roll in the use of the maneuvering to maintain separation behind the heavy. More experience with the new fusion RADAR will help with the timing when vectoring to the finals. Many controllers have been late on turns because of the pace at which this RADAR moves and what we've been used to with the old ASR 9.

Data retrieved from NASA's ASRS site as of July 2013 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.