Narrative:

Cleared for offshore visual to runway 8L. Frequently fly this flight and the last several days have been cleared to maintain 2500 ft until 7 DME. Allowed first officer to descend to 2500 ft, when should have stayed at 3000 ft until 5 DME, since we were not cleared specifically. There was no conflict with traffic, but just because we're normally cleared until 2500 ft, doesn't mean we can always. Didn't really trust first officer to descend comfortably from 3000 ft at 5 DME. Will ask ATC next time.

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Original NASA ASRS Text

Title: CAPT OF AN ACR DIRECTED THE FLYING FO TO DSND EARLY ON A VISUAL APCH OF WHICH A LOWER ALT HAD NOT YET BEEN GIVEN BY APCH CTL.

Narrative: CLRED FOR OFFSHORE VISUAL TO RWY 8L. FREQUENTLY FLY THIS FLT AND THE LAST SEVERAL DAYS HAVE BEEN CLRED TO MAINTAIN 2500 FT UNTIL 7 DME. ALLOWED FO TO DSND TO 2500 FT, WHEN SHOULD HAVE STAYED AT 3000 FT UNTIL 5 DME, SINCE WE WERE NOT CLRED SPECIFICALLY. THERE WAS NO CONFLICT WITH TFC, BUT JUST BECAUSE WE'RE NORMALLY CLRED UNTIL 2500 FT, DOESN'T MEAN WE CAN ALWAYS. DIDN'T REALLY TRUST FO TO DSND COMFORTABLY FROM 3000 FT AT 5 DME. WILL ASK ATC NEXT 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.