Narrative:

I was working local. I had small aircraft a and small aircraft B sequenced #1 and #2 for landing about a mi and a half apart. The small aircraft C called ready on the same runway for departure. When the small aircraft a xed the threshold I told the small aircraft C to taxi into position and hold and to be prepared for an immediate. The small aircraft a was told to taxi west/O delay to the first turnoff and the small aircraft B was told that small aircraft C would depart prior to his arrival. The small aircraft a taxied slower than expected and the small aircraft B progressed faster than anticipated. When the small aircraft a was clear, I cleared the small aircraft C for an immediate takeoff. Although the small aircraft C was airborne before the small aircraft B xed the threshold, I did not have 3000' sep. I deemed it would be safer to let the small aircraft B land than to send him around short final.

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Original NASA ASRS Text

Title: CTLR RELEASED SMA C IN FRONT OF SMA B WHICH RESULTED IN LESS THAN STANDARD SEPARATION. CTLR HAD LESS THAN 3000' BETWEEN THE TWO ACFT. HE NEEDED 3000'.

Narrative: I WAS WORKING LCL. I HAD SMA A AND SMA B SEQUENCED #1 AND #2 FOR LNDG ABOUT A MI AND A HALF APART. THE SMA C CALLED READY ON THE SAME RWY FOR DEP. WHEN THE SMA A XED THE THRESHOLD I TOLD THE SMA C TO TAXI INTO POS AND HOLD AND TO BE PREPARED FOR AN IMMEDIATE. THE SMA A WAS TOLD TO TAXI W/O DELAY TO THE FIRST TURNOFF AND THE SMA B WAS TOLD THAT SMA C WOULD DEPART PRIOR TO HIS ARR. THE SMA A TAXIED SLOWER THAN EXPECTED AND THE SMA B PROGRESSED FASTER THAN ANTICIPATED. WHEN THE SMA A WAS CLR, I CLRED THE SMA C FOR AN IMMEDIATE TKOF. ALTHOUGH THE SMA C WAS AIRBORNE BEFORE THE SMA B XED THE THRESHOLD, I DID NOT HAVE 3000' SEP. I DEEMED IT WOULD BE SAFER TO LET THE SMA B LAND THAN TO SEND HIM AROUND SHORT FINAL.

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.