Narrative:

Air carrier X received a descent to 16000 ft. Acknowledged and read back from R26. R26 xferred communications to R11. Air carrier X descend to 10000 ft. At 14000 ft, air carrier X was 4 1/4 NM behind air carrier Y at 14000 ft. Required separation at 14000 ft is 5 NM. Air carrier X reported on sector 11 frequency communicating to ATC descending to 10000 ft. R11 staffing was one fpl monitoring a developmental who was supposed to receive OJT on radar associate position but was being approved to work the radar position, ie, boot leg training approved by supervisor. Neither the instructor nor the developmental heard air carrier X advise descent to 10000 ft rather than 16000 ft as cleared. Air carrier X high rate of descent when out of 16000 ft, action to stop at 15000 ft not successful because of rate of descent. R26 and R11 observed conflict alert. R26 also observed mode C altitude below assigned altitude -- both in full data block. No evasive action taken. Air carrier X instructed to maintain 12000 ft when controller was advised that the aircraft was through 14000 ft descending. I assume the flight crew 'dialed in' the wrong numbers. Their clearance was 10 mi south lrp at 16000 ft.

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Original NASA ASRS Text

Title: REGIONAL JET ASSIGNED 16000 FT BY ZNY CTLR IS SWITCHED TO ANOTHER FREQ AND RPTS DSNDING TO 10000 FT. ALT DISCREPANCY IS NOT CAUGHT BY ARTCC CTLR RESULTING IN A LOSS OF SEPARATION WITH JETSTREAM AT 14000 FT.

Narrative: ACR X RECEIVED A DSCNT TO 16000 FT. ACKNOWLEDGED AND READ BACK FROM R26. R26 XFERRED COMS TO R11. ACR X DSND TO 10000 FT. AT 14000 FT, ACR X WAS 4 1/4 NM BEHIND ACR Y AT 14000 FT. REQUIRED SEPARATION AT 14000 FT IS 5 NM. ACR X RPTED ON SECTOR 11 FREQ COMMUNICATING TO ATC DSNDING TO 10000 FT. R11 STAFFING WAS ONE FPL MONITORING A DEVELOPMENTAL WHO WAS SUPPOSED TO RECEIVE OJT ON RADAR ASSOCIATE POS BUT WAS BEING APPROVED TO WORK THE RADAR POS, IE, BOOT LEG TRAINING APPROVED BY SUPVR. NEITHER THE INSTRUCTOR NOR THE DEVELOPMENTAL HEARD ACR X ADVISE DSCNT TO 10000 FT RATHER THAN 16000 FT AS CLRED. ACR X HIGH RATE OF DSCNT WHEN OUT OF 16000 FT, ACTION TO STOP AT 15000 FT NOT SUCCESSFUL BECAUSE OF RATE OF DSCNT. R26 AND R11 OBSERVED CONFLICT ALERT. R26 ALSO OBSERVED MODE C ALT BELOW ASSIGNED ALT -- BOTH IN FULL DATA BLOCK. NO EVASIVE ACTION TAKEN. ACR X INSTRUCTED TO MAINTAIN 12000 FT WHEN CTLR WAS ADVISED THAT THE ACFT WAS THROUGH 14000 FT DSNDING. I ASSUME THE FLC 'DIALED IN' THE WRONG NUMBERS. THEIR CLRNC WAS 10 MI S LRP AT 16000 FT.

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.