Narrative:

I was working local control (local control) and we were on a straight xxl in and out configuration going down the east box to ZZZ. I issued 160 heading to all departures routed over ZZZ VOR off xxl. The first thing that happened was east departure called and asked if I could work a C172 up the shoreline through my airspace; I approved this request. A few minutes later I had a couple departures and a few arrivals for xxl. I was monitoring the C172 to make sure they did not conflict with the xxl arrivals. The flm came to me and told me that the TRACON called and advised there was an air carrier Y that had requested to land runway xl. After he told me about this he no longer monitored my position. My first departure (air carrier X) was routed over ZZZ VOR and the air carrier Y was still quite a ways out so I issued a 160 heading and cleared him for take off. When he didn't answer in time I just had him hold short for the next arrival. Once the arrival had landed he was on frequency; so I put in in position and looked at the air carrier Y on final for xl. Now that air carrier Y was a little closer I knew the safest option would be to leave air carrier X on runway heading and let departure climb and turn him over the xl arrival. I had every intention of doing this but I still had 160 written on my strip and apparently I read it off the strip instead of listening to my brain. From this point on I don't know what happened; but I heard from the TRACON that there were still some radio communication problems on their end; but air carrier X was told to expedite his climb. When I was informed of the situation; air carrier X was well above the arrival and I believe they were able to maintain standard separation. I will use this experience in the future to be extra attentive to what I say and to stick to habits that prevent things like this from happening; such as covering the east drop tube which I almost always do but failed to this time.

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Original NASA ASRS Text

Title: Tower and TRACON controllers described a conflict event from different perspectives that involved a departure and arrival operating from intersecting runways.

Narrative: I was working Local Control (LC) and we were on a straight XXL in and out configuration going down the East box to ZZZ. I issued 160 heading to all departures routed over ZZZ VOR off XXL. The first thing that happened was East Departure called and asked if I could work a C172 up the shoreline through my airspace; I approved this request. A few minutes later I had a couple departures and a few arrivals for XXL. I was monitoring the C172 to make sure they did not conflict with the XXL arrivals. The FLM came to me and told me that the TRACON called and advised there was an Air Carrier Y that had requested to land Runway XL. After he told me about this he no longer monitored my position. My first departure (Air Carrier X) was routed over ZZZ VOR and the Air Carrier Y was still quite a ways out so I issued a 160 heading and cleared him for take off. When he didn't answer in time I just had him hold short for the next arrival. Once the arrival had landed he was on frequency; so I put in in position and looked at the Air Carrier Y on final for XL. Now that Air Carrier Y was a little closer I knew the safest option would be to leave Air Carrier X on runway heading and let departure climb and turn him over the XL arrival. I had every intention of doing this but I still had 160 written on my strip and apparently I read it off the strip instead of listening to my brain. From this point on I don't know what happened; but I heard from the TRACON that there were still some radio communication problems on their end; but Air Carrier X was told to expedite his climb. When I was informed of the situation; Air Carrier X was well above the arrival and I believe they were able to maintain standard separation. I will use this experience in the future to be extra attentive to what I say and to stick to habits that prevent things like this from happening; such as covering the East drop tube which I almost always do but failed to this time.

Data retrieved from NASA's ASRS site as of April 2012 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.