Narrative:

Events leading up to the loss of separation are as follows; a runway change was in progress from 30's/35 to 30's/17. This slightly changed the dynamic of my airspace; thus forced me to reroute two airplanes under my control at the time. I released a MU2 off of a satellite airport and observed his tag acquire off the departure end; however I was not able to raise the aircraft on my radio frequency. After five or six miles I called the satellite airport and asked them to try and ship the MU2 again. The MU2 called me when they were about 10 to 12 miles at 2;500 ft. This in return changed the original plan for the departure controller to work the airplane because the MU2 was already 20 miles south of our class B airport. After I was given the point out approval by the departure controller that it was my airplane to work out high; I climbed the MU2 to 12;000. Thereafter; due to our runway change; I saw it necessary to turn the MU2 from a 180 heading to a 90 heading for a brief period of time to allow for the class B airport's arrival aircraft to descend below. The departure controller was working an E170 departure off the class B airport. After passing pertinent class B arrival traffic the departure controller cleared the E170 to 17;000 and at some point in the near future cleared them to a fix to join one of our SID's. I was scanning the scope and working other aircraft when I observed the conflict between these two airplanes. I was not positive what direction the E170 was turning to so I called traffic for the MU2. The MU2 saw the E170 but by this time the separation was already lost. Recommendation; the decision making process between the two controllers involved needed to be changed. I was busy enough where I didn't need to be working airplanes out of my airspace altitudes that high anyway. I have no doubt in my mind that if the departure controller was working both airplanes there would have been no deal.

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Original NASA ASRS Text

Title: TRACON Controller described a loss of separation event noting the decision making process between the two controllers involved was less than required.

Narrative: Events leading up to the loss of separation are as follows; a runway change was in progress from 30's/35 to 30's/17. This slightly changed the dynamic of my airspace; thus forced me to reroute two airplanes under my control at the time. I released a MU2 off of a satellite airport and observed his tag acquire off the departure end; however I was not able to raise the aircraft on my radio frequency. After five or six miles I called the satellite airport and asked them to try and ship the MU2 again. The MU2 called me when they were about 10 to 12 miles at 2;500 FT. This in return changed the original plan for the Departure Controller to work the airplane because the MU2 was already 20 miles south of our Class B airport. After I was given the point out approval by the Departure Controller that it was my airplane to work out high; I climbed the MU2 to 12;000. Thereafter; due to our runway change; I saw it necessary to turn the MU2 from a 180 heading to a 90 heading for a brief period of time to allow for the Class B airport's arrival aircraft to descend below. The Departure Controller was working an E170 departure off the Class B airport. After passing pertinent Class B arrival traffic the Departure Controller cleared the E170 to 17;000 and at some point in the near future cleared them to a fix to join one of our SID's. I was scanning the scope and working other aircraft when I observed the conflict between these two airplanes. I was not positive what direction the E170 was turning to so I called traffic for the MU2. The MU2 saw the E170 but by this time the separation was already lost. Recommendation; the decision making process between the two controllers involved needed to be changed. I was busy enough where I didn't need to be working airplanes out of my airspace altitudes that high anyway. I have no doubt in my mind that if the Departure Controller was working both airplanes there would have been no deal.

Data retrieved from NASA's ASRS site as of April 2012 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.