Narrative:

A coast guard AS65 dauphin called as a rescue wanting to depart east and E13 and depart shoreline north. After all the appropriate coordination had been performed; I cleared him for takeoff and issued 'proceed direct to the shoreline then cleared out of bravo airspace as requested.' at this time an A320 had begun his takeoff roll on [runway] 24L. The dauphin traveled westbound along taxiway east then appeared to follow taxiway bb to cross [runway] 24L airborne and continue to the shoreline. As the asde alerted; I advised the dauphin that his instructions were direct to the shore and advised him of traffic. He continued to the shoreline and I cleared him out and gave frequency change. I had the opportunity to review replays and recording of the incident. Even though the phraseology I used has worked in the past; seeing it from the pilot's perspective it seemed as though a bit ambiguous. I have reviewed ways in which I can 'tighten' up the phraseology and use more descriptive instructions to ensure the helicopters will remain in between the complexes. I feel that issuing traffic that would be off [runway] 24L; even if not a factor; would be a good practice just to keep the pilot in the 'know' of what is going on. This is also a good reminder to be vigilant in read backs because as I reviewed the tape; the pilot read back cleared out direct north while I thought he said direct shore and did not realize because he flew westbound towards the shore on departure. I also feel that a standard coast guard departure could be put in place that would entail the aircraft taking off; remaining between the complexes; then cleared out north/south at the shoreline unless otherwise specifically noted to reduce phraseology and have everybody on the same page.

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Original NASA ASRS Text

Title: LAX Tower Controller described an ASDE identified conflict when a Coast Guard helicopter departing on a 'rescue' mission failed to follow normal instructions; turn at the beach' and turn north early.

Narrative: A Coast Guard AS65 Dauphin called as a rescue wanting to depart E and E13 and depart shoreline north. After all the appropriate coordination had been performed; I cleared him for takeoff and issued 'proceed direct to the shoreline then cleared out of Bravo Airspace as requested.' At this time an A320 had begun his takeoff roll on [Runway] 24L. The Dauphin traveled westbound along Taxiway E then appeared to follow Taxiway BB to cross [Runway] 24L airborne and continue to the shoreline. As the ASDE alerted; I advised the Dauphin that his instructions were direct to the shore and advised him of traffic. He continued to the shoreline and I cleared him out and gave frequency change. I had the opportunity to review replays and recording of the incident. Even though the phraseology I used has worked in the past; seeing it from the pilot's perspective it seemed as though a bit ambiguous. I have reviewed ways in which I can 'tighten' up the phraseology and use more descriptive instructions to ensure the helicopters will remain in between the complexes. I feel that issuing traffic that would be off [Runway] 24L; even if not a factor; would be a good practice just to keep the pilot in the 'know' of what is going on. This is also a good reminder to be vigilant in read backs because as I reviewed the tape; the pilot read back cleared out direct north while I thought he said direct shore and did not realize because he flew westbound towards the shore on departure. I also feel that a standard Coast Guard departure could be put in place that would entail the aircraft taking off; remaining between the complexes; then cleared out north/south at the shoreline unless otherwise specifically noted to reduce phraseology and have everybody on the same page.

Data retrieved from NASA's ASRS site as of July 2013 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.