Narrative:

I was working local control and had been on the position for about one hour. It was just after a busy departure push. I cleared air carrier X for takeoff on runway 15R and issued a right turn heading 330 degree at 1 DME. Approach was bringing small aircraft Y for an approach to runway 4, a nonstandard runway not active at the time. There was no coordination on these operation. The first time I was aware of a problem was when approach called and asked if I had the small aircraft Y in sight. I did not. On initial contact I called traffic to small aircraft Y and he reported the air carrier in sight. However by that time separation was already lost. I feel the basic cause of this problem was the failure of proper coordination and my inattentiveness to watch all my airspace all the time. In addition the air carrier received a TCASII RA that told him to descend below the traffic. I feel if he kept climbing he would have cleared the traffic no problem. Supplemental information from acn 209902. Air carrier X departing runway 15R, turning right and climbing out during departure, receives TCASII alert on small aircraft aircraft descending VFR into runway 4. Air carrier X reacts to alert, leveling then descending below VFR aircraft. In my opinion, had air carrier X continued climb out, no error would have occurred. Additionally, it is my understanding, that the air carrier X crew had the small aircraft Y in sight and still responded to the TCASII command.

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Original NASA ASRS Text

Title: ACR X TCASII RA DSND HAD LTSS FROM SMA Y. SYS ERROR. EVASIVE ACTION TAKEN.

Narrative: I WAS WORKING LCL CTL AND HAD BEEN ON THE POS FOR ABOUT ONE HR. IT WAS JUST AFTER A BUSY DEP PUSH. I CLRED ACR X FOR TKOF ON RWY 15R AND ISSUED A R TURN HDG 330 DEG AT 1 DME. APCH WAS BRINGING SMA Y FOR AN APCH TO RWY 4, A NONSTANDARD RWY NOT ACTIVE AT THE TIME. THERE WAS NO COORD ON THESE OP. THE FIRST TIME I WAS AWARE OF A PROBLEM WAS WHEN APCH CALLED AND ASKED IF I HAD THE SMA Y IN SIGHT. I DID NOT. ON INITIAL CONTACT I CALLED TFC TO SMA Y AND HE RPTED THE ACR IN SIGHT. HOWEVER BY THAT TIME SEPARATION WAS ALREADY LOST. I FEEL THE BASIC CAUSE OF THIS PROBLEM WAS THE FAILURE OF PROPER COORD AND MY INATTENTIVENESS TO WATCH ALL MY AIRSPACE ALL THE TIME. IN ADDITION THE ACR RECEIVED A TCASII RA THAT TOLD HIM TO DSND BELOW THE TFC. I FEEL IF HE KEPT CLBING HE WOULD HAVE CLRED THE TFC NO PROBLEM. SUPPLEMENTAL INFO FROM ACN 209902. ACR X DEPARTING RWY 15R, TURNING R AND CLBING OUT DURING DEP, RECEIVES TCASII ALERT ON SMA ACFT DSNDING VFR INTO RWY 4. ACR X REACTS TO ALERT, LEVELING THEN DSNDING BELOW VFR ACFT. IN MY OPINION, HAD ACR X CONTINUED CLBOUT, NO ERROR WOULD HAVE OCCURRED. ADDITIONALLY, IT IS MY UNDERSTANDING, THAT THE ACR X CREW HAD THE SMA Y IN SIGHT AND STILL RESPONDED TO THE TCASII COMMAND.

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.