Narrative:

I cleared air carrier X, A320, for immediate takeoff on runway 9L using anticipated separation. LJ25 was cleared to land on runway 17 (intersecting). By the time air carrier X rolled, I realized standard separation would not exist when learjet crossed landing threshold for runway 17. I then asked the supervisor if I should send LJ25 around. The supervisor did not respond to me. I then realized it would be safer for LJ25 to land rather than go around and create a possible airborne conflict with air carrier X who was taking off. LJ25 landed safely and did not come closer than 5000 ft to air carrier X before air carrier X rotated. It was a 'technical' loss of runway separation but a very controled one. The biggest problem was that the supervisor 'froze' when he was asked for assistance.

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Original NASA ASRS Text

Title: PHL LCL CTLR EXPERIENCED LOSS OF SEPARATION BTWN LNDG AND DEPARTING TFC ON INTERSECTING RWYS.

Narrative: I CLRED ACR X, A320, FOR IMMEDIATE TKOF ON RWY 9L USING ANTICIPATED SEPARATION. LJ25 WAS CLRED TO LAND ON RWY 17 (INTERSECTING). BY THE TIME ACR X ROLLED, I REALIZED STANDARD SEPARATION WOULD NOT EXIST WHEN LEARJET CROSSED LNDG THRESHOLD FOR RWY 17. I THEN ASKED THE SUPVR IF I SHOULD SEND LJ25 AROUND. THE SUPVR DID NOT RESPOND TO ME. I THEN REALIZED IT WOULD BE SAFER FOR LJ25 TO LAND RATHER THAN GO AROUND AND CREATE A POSSIBLE AIRBORNE CONFLICT WITH ACR X WHO WAS TAKING OFF. LJ25 LANDED SAFELY AND DID NOT COME CLOSER THAN 5000 FT TO ACR X BEFORE ACR X ROTATED. IT WAS A 'TECHNICAL' LOSS OF RWY SEPARATION BUT A VERY CTLED ONE. THE BIGGEST PROB WAS THAT THE SUPVR 'FROZE' WHEN HE WAS ASKED FOR ASSISTANCE.

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.