Narrative:

I was working local control and had 2 aircraft on frequency--air carrier X that was entering the runway for takeoff, and cga Y on base leg for landing on the same runway. I cleared air carrier X for takeoff with no delay, and gave the position of the cga. Air carrier X entered the runway and started rolling with no increase in speed. Cga Y was on a very close base, in a rapid descent. By the time cga Y turned final, he was only about 1/2 mi from the runway end. Air carrier X had just begun its roll. It became clear at this point that I would not have 6000' between the 2 aircraft; however, cga Y was so low that I felt a go around would be unsafe. I asked the supervisor if I should send him around. He said no. When cga Y crossed the threshold, air carrier X was rotating about 4500' down the runway.

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Original NASA ASRS Text

Title: ACFT LANDED WHILE ANOTHER ACFT WAS STILL ON THE RWY.

Narrative: I WAS WORKING LCL CTL AND HAD 2 ACFT ON FREQ--ACR X THAT WAS ENTERING THE RWY FOR TKOF, AND CGA Y ON BASE LEG FOR LNDG ON THE SAME RWY. I CLRED ACR X FOR TKOF WITH NO DELAY, AND GAVE THE POS OF THE CGA. ACR X ENTERED THE RWY AND STARTED ROLLING WITH NO INCREASE IN SPD. CGA Y WAS ON A VERY CLOSE BASE, IN A RAPID DSCNT. BY THE TIME CGA Y TURNED FINAL, HE WAS ONLY ABOUT 1/2 MI FROM THE RWY END. ACR X HAD JUST BEGUN ITS ROLL. IT BECAME CLEAR AT THIS POINT THAT I WOULD NOT HAVE 6000' BTWN THE 2 ACFT; HOWEVER, CGA Y WAS SO LOW THAT I FELT A GAR WOULD BE UNSAFE. I ASKED THE SUPVR IF I SHOULD SEND HIM AROUND. HE SAID NO. WHEN CGA Y CROSSED THE THRESHOLD, ACR X WAS ROTATING ABOUT 4500' DOWN THE RWY.

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.