Narrative:

Fll approach was very busy and the controller gave us a rushed clearance: at wisci (which is on the mrlin 3 arrival, fll) turn heading 270 degrees, 210 KT speed, descend 6000 ft. In our haste to comply we read back 4000 ft and then proceeded to do so. A few mins later the controller asked our assigned altitude to which we said 4000 ft. He then said we must have got someone else's clearance. We thought 4000 ft was our altitude because we read it back that way, however, there was a lot of confusion on the frequency which led us to the wrong altitude.

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Original NASA ASRS Text

Title: RPTRS FAILED TO COMPLY WITH ALT ASSIGNMENT. THE TRACON WORKLOAD WAS HIGH, THE FREQ WAS CONGESTED. THE RPTR HEARD AND READ BACK AND DSNDED TO 4000 FT, WHILE THE TRACON INTENDED THE RPTRS TO DSND ONLY TO 6000 FT.

Narrative: FLL APCH WAS VERY BUSY AND THE CTLR GAVE US A RUSHED CLRNC: AT WISCI (WHICH IS ON THE MRLIN 3 ARR, FLL) TURN HDG 270 DEGS, 210 KT SPD, DSND 6000 FT. IN OUR HASTE TO COMPLY WE READ BACK 4000 FT AND THEN PROCEEDED TO DO SO. A FEW MINS LATER THE CTLR ASKED OUR ASSIGNED ALT TO WHICH WE SAID 4000 FT. HE THEN SAID WE MUST HAVE GOT SOMEONE ELSE'S CLRNC. WE THOUGHT 4000 FT WAS OUR ALT BECAUSE WE READ IT BACK THAT WAY, HOWEVER, THERE WAS A LOT OF CONFUSION ON THE FREQ WHICH LED US TO THE WRONG ALT.

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.