Narrative:

We were cleared to depart lax via the 'loop six' departure (LOOP6.lax) from runway 25R. The loop six for runway 25R reads as follows (verbatim): climb heading 250 to cross smo R-160 at or below 3;000 ft (ATC)/at or above 415 ft; then turn left heading 235. Expect radar vectors to cross lax at or above 10;000 ft (ATC)/at or above 3;400 ft. Both the PIC and I misinterpreted this SID. We thought that what was expected of us is to turn to a 235 heading out of 415 ft while crossing the smo R-160 at or below 3;000 ft on that 235 heading. As such; I initiated a left turn at 415 ft to a 235 heading. Lax tower immediately called us and told us to return to a 250 heading; which I immediately complied with. A few seconds later the tower controller directed us to turn left to a 235 heading and handed us over to lax departure control. No traffic alert/conflict had occurred. The reminder of the flight went uneventful. Suggestions; if in doubt what it is that we are supposed to do per a SID; call clearance delivery and clarify it! However; the problem in our particular scenario was that we had no doubt as to how we read the SID procedure. We both were in agreement that a turn to a 235 heading was supposed to be initiated at 415 ft.

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Original NASA ASRS Text

Title: Corporate aircraft departing LAX on the LOOP 6 SID initiated a left turn at 415 FT but were re-cleared by ATC to continue on the 250 heading; reporters noting confusing language on the chart.

Narrative: We were cleared to depart LAX via the 'LOOP SIX' departure (LOOP6.LAX) from Runway 25R. The LOOP Six for Runway 25R reads as follows (verbatim): Climb heading 250 to cross SMO R-160 at or below 3;000 FT (ATC)/at or above 415 FT; then turn LEFT heading 235. Expect RADAR vectors to cross LAX at or above 10;000 FT (ATC)/at or above 3;400 FT. Both the PIC and I misinterpreted this SID. We thought that what was expected of us is to turn to a 235 heading out of 415 FT while crossing the SMO R-160 at or below 3;000 FT on that 235 heading. As such; I initiated a left turn at 415 FT to a 235 heading. LAX Tower immediately called us and told us to return to a 250 heading; which I immediately complied with. A few seconds later the Tower Controller directed us to turn left to a 235 heading and handed us over to LAX Departure Control. No traffic alert/conflict had occurred. The reminder of the flight went uneventful. Suggestions; if in doubt what it is that we are supposed to do per a SID; call Clearance Delivery and clarify it! However; the problem in our particular scenario was that we had no doubt as to how we read the SID procedure. We both were in agreement that a turn to a 235 heading was supposed to be initiated at 415 FT.

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.