Narrative:

I was working local control at sfo tower and cleared air carrier X for takeoff on runway 28L. He departed straight out on the sfo 281 radial. As soon as he was airborne he reported helicopter Y traffic directly off his nose. I looked and saw air carrier X making a slight right s-turn and helicopter Y sbound off his left wing at approximately 500 ft. I had previously given helicopter Y a TCA clearance along the freeway at or below 700 ft, just as he was doing. Factors leading to the event are as follows: very busy with arrs, landing simultaneous visual approachs on runway 28L and 28R. I had at least 3 heavy jet departures waiting for a runway 28 departure slot. The primary departure runways were runways 01 and had approximately 5 aircraft waiting at each one of those runways. I had 2 transitions. One, a helicopter northbound from sfo to the north end of the TCA. And the other a helicopter Y from the north end of the TCA to the south end. Both passed to the west end of the airport. A common route for transitions. I had a rather tight hole on final for runway 28L and decided to depart air carrier X in it. It looked like the only chance to depart runway 28 in a while. I cleared air carrier X for takeoff and watched closely the separation succeeding him, an air carrier on short final, who I was already planning a possible go around for but let it go because the separation existed. My attention was there instead of on the departure path of air carrier Y. One other factor was that the ARTS tag on the radar of the transition was in 'track suspense'. It removes clutter from the scope and prevents tags from dropping into 'coast' when they approach the airport boundary. This is a common procedure in the tower. I also did not use a strip holder (which we use for a visual aid to hold aircraft) I had available to me. I use it most of the time and did not this time.

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Original NASA ASRS Text

Title: ACR X HAD NMAC LTSS FROM HELI Y. SYS ERROR. EVASIVE ACTION TAKEN.

Narrative: I WAS WORKING LCL CTL AT SFO TWR AND CLRED ACR X FOR TKOF ON RWY 28L. HE DEPARTED STRAIGHT OUT ON THE SFO 281 RADIAL. AS SOON AS HE WAS AIRBORNE HE RPTED HELI Y TFC DIRECTLY OFF HIS NOSE. I LOOKED AND SAW ACR X MAKING A SLIGHT R S-TURN AND HELI Y SBOUND OFF HIS L WING AT APPROX 500 FT. I HAD PREVIOUSLY GIVEN HELI Y A TCA CLRNC ALONG THE FREEWAY AT OR BELOW 700 FT, JUST AS HE WAS DOING. FACTORS LEADING TO THE EVENT ARE AS FOLLOWS: VERY BUSY WITH ARRS, LNDG SIMULTANEOUS VISUAL APCHS ON RWY 28L AND 28R. I HAD AT LEAST 3 HVY JET DEPS WAITING FOR A RWY 28 DEP SLOT. THE PRIMARY DEP RWYS WERE RWYS 01 AND HAD APPROX 5 ACFT WAITING AT EACH ONE OF THOSE RWYS. I HAD 2 TRANSITIONS. ONE, A HELI NBOUND FROM SFO TO THE N END OF THE TCA. AND THE OTHER A HELI Y FROM THE N END OF THE TCA TO THE S END. BOTH PASSED TO THE W END OF THE ARPT. A COMMON RTE FOR TRANSITIONS. I HAD A RATHER TIGHT HOLE ON FINAL FOR RWY 28L AND DECIDED TO DEPART ACR X IN IT. IT LOOKED LIKE THE ONLY CHANCE TO DEPART RWY 28 IN A WHILE. I CLRED ACR X FOR TKOF AND WATCHED CLOSELY THE SEPARATION SUCCEEDING HIM, AN ACR ON SHORT FINAL, WHO I WAS ALREADY PLANNING A POSSIBLE GAR FOR BUT LET IT GO BECAUSE THE SEPARATION EXISTED. MY ATTN WAS THERE INSTEAD OF ON THE DEP PATH OF ACR Y. ONE OTHER FACTOR WAS THAT THE ARTS TAG ON THE RADAR OF THE TRANSITION WAS IN 'TRACK SUSPENSE'. IT REMOVES CLUTTER FROM THE SCOPE AND PREVENTS TAGS FROM DROPPING INTO 'COAST' WHEN THEY APCH THE ARPT BOUNDARY. THIS IS A COMMON PROC IN THE TWR. I ALSO DID NOT USE A STRIP HOLDER (WHICH WE USE FOR A VISUAL AID TO HOLD ACFT) I HAD AVAILABLE TO ME. I USE IT MOST OF THE TIME AND DID NOT THIS TIME.

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.