Narrative:

The small aircraft X described above was holding short of runway 17 and called ready to depart (he was IFR with a release for runway heading). I instructed him, 'no delay, traffic is an small aircraft Y on a 1 mi right base, fly runway heading, cleared for takeoff.' small aircraft X acknowledged and taxied onto runway. I instructed the small aircraft Y, 'square your turn to final, traffic is an small aircraft X departing runway 17.' he acknowledged also. The small aircraft Y did not square pattern much and small aircraft X was slow departing. The result was about 2000' sep. Both aircraft were airborne. I did not send small aircraft Y around because both aircraft would have ben climbing into each other. I should have held the small aircraft X short of runway until after small aircraft Y had landed and not run the traffic so tight. Pilots contributed because small aircraft Y did not square his pattern or slow down after acknowledging small aircraft X traffic. Small aircraft X did not depart west/O delay--in fact was unusually slow departing. Note: the small aircraft Y had been cleared to land runway 17 when eh reported entering a 2 mi right base. The wind was 180 degrees at about 22 KTS, and had been slowing small planes down pretty good on final all day.

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Original NASA ASRS Text

Title: CTLR ALLOWED AN SMA TO DEPART IN FRONT OF A LNDG SMA ON THE SAME RWY RESULTING IN LESS THAN STANDARD SEPARATION.

Narrative: THE SMA X DESCRIBED ABOVE WAS HOLDING SHORT OF RWY 17 AND CALLED READY TO DEPART (HE WAS IFR WITH A RELEASE FOR RWY HDG). I INSTRUCTED HIM, 'NO DELAY, TFC IS AN SMA Y ON A 1 MI RIGHT BASE, FLY RWY HDG, CLRED FOR TKOF.' SMA X ACKNOWLEDGED AND TAXIED ONTO RWY. I INSTRUCTED THE SMA Y, 'SQUARE YOUR TURN TO FINAL, TFC IS AN SMA X DEPARTING RWY 17.' HE ACKNOWLEDGED ALSO. THE SMA Y DID NOT SQUARE PATTERN MUCH AND SMA X WAS SLOW DEPARTING. THE RESULT WAS ABOUT 2000' SEP. BOTH ACFT WERE AIRBORNE. I DID NOT SEND SMA Y AROUND BECAUSE BOTH ACFT WOULD HAVE BEN CLBING INTO EACH OTHER. I SHOULD HAVE HELD THE SMA X SHORT OF RWY UNTIL AFTER SMA Y HAD LANDED AND NOT RUN THE TFC SO TIGHT. PLTS CONTRIBUTED BECAUSE SMA Y DID NOT SQUARE HIS PATTERN OR SLOW DOWN AFTER ACKNOWLEDGING SMA X TFC. SMA X DID NOT DEPART W/O DELAY--IN FACT WAS UNUSUALLY SLOW DEPARTING. NOTE: THE SMA Y HAD BEEN CLRED TO LAND RWY 17 WHEN EH RPTED ENTERING A 2 MI RIGHT BASE. THE WIND WAS 180 DEGS AT ABOUT 22 KTS, AND HAD BEEN SLOWING SMALL PLANES DOWN PRETTY GOOD ON FINAL ALL DAY.

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.