Narrative:

Small aircraft tower released 3 aircraft same route that were not compatible (i.e., slow, faster, fastest). I found myself vectoring for separation. The first aircraft Y had to go about 20 NM west opposite direction to lax departure traffic. Air carrier X off lax was climbing through 9000 ft slowly towards the first aircraft Y. I turned the aircraft sbound away from air carrier X, but air carrier X received a TCASII alert and began descent on his own, even though the 2 were diverging. Recommend towers sequence departures on the ground for speed compatibility to avoid airborne conflicts.

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Original NASA ASRS Text

Title: ACR X TCASII RA FROM ACFT Y. NON ADHERENCE TO ATC CLRNC DSND. EVASIVE ACTION TAKEN.

Narrative: SMA TWR RELEASED 3 ACFT SAME RTE THAT WERE NOT COMPATIBLE (I.E., SLOW, FASTER, FASTEST). I FOUND MYSELF VECTORING FOR SEPARATION. THE FIRST ACFT Y HAD TO GO ABOUT 20 NM W OPPOSITE DIRECTION TO LAX DEP TFC. ACR X OFF LAX WAS CLBING THROUGH 9000 FT SLOWLY TOWARDS THE FIRST ACFT Y. I TURNED THE ACFT SBOUND AWAY FROM ACR X, BUT ACR X RECEIVED A TCASII ALERT AND BEGAN DSCNT ON HIS OWN, EVEN THOUGH THE 2 WERE DIVERGING. RECOMMEND TWRS SEQUENCE DEPS ON THE GND FOR SPD COMPATIBILITY TO AVOID AIRBORNE CONFLICTS.

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.