Narrative:

Location: hobee 360 degree radial, 120 DME. We (trip 1) had been following trip 2 approximately 40 NM in trail for our entire en route portion of jfk-mia. At approximately 120 NM north of hobee, proceeding direct to hobee, ZJX cleared us (trip 1) to descend to FL280, to which we acknowledged. TCASII showed an aircraft below us at FL290 heading the opposite direction. Although that aircraft was off of our left wing at the 5 mi radius on TCASII, we let him pass before initiating our descent. Less than 1 min later, ZJX again cleared us to FL280, to which we responded 'we are passing FL300 for FL280.' the controller answered that the previous clearance was for trip 2 and not trip 1, but as long as we were descending to continue down to FL280. Upon hearing this, the other aircraft informed ZJX that they had never been given FL280 and that controllers had been mixing us up all night. ATC then cleared trip 2 to descend from FL310 to FL280. This ended the event. Scheduling such similar call signs on the same route at the same time can only lead to this type of confusion.

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Original NASA ASRS Text

Title: CTLR MIXING 2 RADIO CALL SIGNS FOR SAME COMPANY ACFT. FLC FOLLOWS DSCNT CLRNC INTENDED FOR PROCEEDING ACFT.

Narrative: LOCATION: HOBEE 360 DEG RADIAL, 120 DME. WE (TRIP 1) HAD BEEN FOLLOWING TRIP 2 APPROX 40 NM IN TRAIL FOR OUR ENTIRE ENRTE PORTION OF JFK-MIA. AT APPROX 120 NM N OF HOBEE, PROCEEDING DIRECT TO HOBEE, ZJX CLRED US (TRIP 1) TO DSND TO FL280, TO WHICH WE ACKNOWLEDGED. TCASII SHOWED AN ACFT BELOW US AT FL290 HDG THE OPPOSITE DIRECTION. ALTHOUGH THAT ACFT WAS OFF OF OUR L WING AT THE 5 MI RADIUS ON TCASII, WE LET HIM PASS BEFORE INITIATING OUR DSCNT. LESS THAN 1 MIN LATER, ZJX AGAIN CLRED US TO FL280, TO WHICH WE RESPONDED 'WE ARE PASSING FL300 FOR FL280.' THE CTLR ANSWERED THAT THE PREVIOUS CLRNC WAS FOR TRIP 2 AND NOT TRIP 1, BUT AS LONG AS WE WERE DSNDING TO CONTINUE DOWN TO FL280. UPON HEARING THIS, THE OTHER ACFT INFORMED ZJX THAT THEY HAD NEVER BEEN GIVEN FL280 AND THAT CTLRS HAD BEEN MIXING US UP ALL NIGHT. ATC THEN CLRED TRIP 2 TO DSND FROM FL310 TO FL280. THIS ENDED THE EVENT. SCHEDULING SUCH SIMILAR CALL SIGNS ON THE SAME RTE AT THE SAME TIME CAN ONLY LEAD TO THIS TYPE OF CONFUSION.

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.