Narrative:

Medium large transport X was on a right downwind. Medium large transport X was turned base leg at 4000 ft and instructed to descend to 3000 ft for runway 29L. Light transport Y was wbound at 4000 ft inbound to runway 29R. An advisory of the crossing traffic was issued to light transport Y. It appeared medium large transport X was not descending or turning. Medium large transport X was turned further west to stay ahead of light transport Y. A TA was reissued to light transport Y and the traffic was reported in sight. Medium large transport X reported the runway and both aircraft continued inbound without further incident. At the time medium large transport X was turned base, the 2 aircraft were separated by ample distance to allow the normal descent of 1000 ft by medium large transport X. It appeared medium large transport X was not turning or descending as instructed and lateral separation was lost quickly.

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Original NASA ASRS Text

Title: ACR MLG DIDN'T RESPOND TO ATC CLRNC IN A TIMELY MANNER AND CAUSED LTSS WITH SMT ACFT ON VECTORS TO ARPT.

Narrative: MLG X WAS ON A R DOWNWIND. MLG X WAS TURNED BASE LEG AT 4000 FT AND INSTRUCTED TO DSND TO 3000 FT FOR RWY 29L. LTT Y WAS WBOUND AT 4000 FT INBOUND TO RWY 29R. AN ADVISORY OF THE XING TFC WAS ISSUED TO LTT Y. IT APPEARED MLG X WAS NOT DSNDING OR TURNING. MLG X WAS TURNED FURTHER W TO STAY AHEAD OF LTT Y. A TA WAS REISSUED TO LTT Y AND THE TFC WAS RPTED IN SIGHT. MLG X RPTED THE RWY AND BOTH ACFT CONTINUED INBOUND WITHOUT FURTHER INCIDENT. AT THE TIME MLG X WAS TURNED BASE, THE 2 ACFT WERE SEPARATED BY AMPLE DISTANCE TO ALLOW THE NORMAL DSCNT OF 1000 FT BY MLG X. IT APPEARED MLG X WAS NOT TURNING OR DSNDING AS INSTRUCTED AND LATERAL SEPARATION WAS LOST QUICKLY.

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.