I90 controller describes a loss of separation he finds out by the tool tarp advising the wake turbul...

Narrative:

Aircraft Y; the heavy; was the lead aircraft on the north downwind for runway 26L. Aircraft X; the large; was the following aircraft on the same downwind but en-route to runway 27. Aircraft Y was descending to 2000 feet and aircraft X was descending to 3000 feet initially. I turned the heavy out of 5000 feet for the right base. More than minimum separation existed when I turned the heavy southbound. Tarp [traffic analysis review program] claims I flew through the wake remnant of the heavy with the large on the downwind even though I had more than 5 miles behind the heavy when the heavy started the base. I pointed the heavy on the base leg out to aircraft X while he was still on the downwind. Aircraft X reported the heavy in sight and was instructed to maintain visual separation. I did so because I knew I'd be turning behind the heavy for the base leg to runway 27 and I wanted to ensure I was protected. Tarp claims closest proximity was 400 feet vertical and 4.13 miles lateral. Those distances are approximate from my recollection of looking at the replay. I'm at a loss for words about how this was an operational error. I had more than minimum separation laterally when the heavy turned southbound on the base leg. I don't mess with wake turbulence and probably had a *T line drawn to ensure spacing. I used the tools available to me to maintain separation. If tarp can see wake remnant and call a deal on me; why doesn't tarp provide me with a tool to avoid said remnant. As I said above; I used the tools available to me.

Original NASA ASRS Text

Title: I90 Controller describes a loss of separation he finds out by the tool TARP advising the wake turbulence remnant. Controller wonders if this tool (TARP) can tell them that there was a loss of separation why can't it provide the controller information to prevent the loss.

Narrative: Aircraft Y; the heavy; was the lead aircraft on the north downwind for runway 26L. Aircraft X; the large; was the following aircraft on the same downwind but en-route to runway 27. Aircraft Y was descending to 2000 feet and Aircraft X was descending to 3000 feet initially. I turned the heavy out of 5000 feet for the right base. More than minimum separation existed when I turned the heavy southbound. TARP [Traffic Analysis Review Program] claims I flew through the wake remnant of the heavy with the large on the downwind even though I had more than 5 miles behind the heavy when the heavy started the base. I pointed the heavy on the base leg out to Aircraft X while he was still on the downwind. Aircraft X reported the heavy in sight and was instructed to maintain visual separation. I did so because I knew I'd be turning behind the heavy for the base leg to runway 27 and I wanted to ensure I was protected. TARP claims closest proximity was 400 feet vertical and 4.13 miles lateral. Those distances are approximate from my recollection of looking at the replay. I'm at a loss for words about how this was an operational error. I had more than minimum separation laterally when the heavy turned southbound on the base leg. I don't mess with wake turbulence and probably had a *T line drawn to ensure spacing. I used the tools available to me to maintain separation. If TARP can see wake remnant and call a deal on me; why doesn't TARP provide me with a tool to avoid said remnant. As I said above; I used the tools available to me.

Data retrieved from NASA's ASRS site 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.

Attributes
ACN	1232497
Time
Date	201412
Local Time Of Day	0001-0600
Place
Locale Reference	I90.TRACON
State Reference	TX
Aircraft 1
Make Model Name	Medium Large Transport
Operating Under FAR Part	Part 121
Flight Phase	Descent
Route In Use	Vectors
Flight Plan	IFR
Aircraft 2
Make Model Name	Widebody Low Wing 2 Turbojet Eng
Operating Under FAR Part	Part 121
Flight Phase	Descent
Route In Use	Vectors
Flight Plan	IFR
Person 1
Function	Approach
Qualification	Air Traffic Control Fully Certified
Experience	Air Traffic Control Time Certified In Pos 1 (yrs) 4
Events
Anomaly	ATC Issue All Types Deviation - Procedural Published Material / Policy Inflight Event / Encounter Wake Vortex Encounter

I90 controller describes a loss of separation he finds out by the tool tarp advising the wake turbulence remnant. Controller wonders if this tool (tarp) can tell them that there was a loss of separation why can't it provide the controller information to prevent the loss.