Narrative:

During cruise at 35,000' center called 'air carrier XXX descend to FL240.' a few seconds later center called and asked us to expedite through FL330. We increased our rate of descent to comply. Then center then called us and stated there was a different company XXX on frequency and that they wanted us to go back to FL350. She made several calls after that only using the numbers 'XXX' possibly 'microphone' problems or just bad communication. Supplemental information from acn 126300: center cleared our flight to lower altitude then discovered he called wrong flight # mixed with another flight with same last digits. Called and told us to climb to previous altitude. We complied.

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Original NASA ASRS Text

Title: SIMILAR ACFT CALL SIGNS ON FREQ. ARTCC RADAR CTLR DESCENDED WRONG ACFT. OPERATIONAL DEVIATION.

Narrative: DURING CRUISE AT 35,000' CENTER CALLED 'ACR XXX DSND TO FL240.' A FEW SECONDS LATER CENTER CALLED AND ASKED US TO EXPEDITE THROUGH FL330. WE INCREASED OUR RATE OF DSCNT TO COMPLY. THEN CENTER THEN CALLED US AND STATED THERE WAS A DIFFERENT COMPANY XXX ON FREQ AND THAT THEY WANTED US TO GO BACK TO FL350. SHE MADE SEVERAL CALLS AFTER THAT ONLY USING THE NUMBERS 'XXX' POSSIBLY 'MIKE' PROBLEMS OR JUST BAD COM. SUPPLEMENTAL INFORMATION FROM ACN 126300: CENTER CLRED OUR FLT TO LOWER ALT THEN DISCOVERED HE CALLED WRONG FLT # MIXED WITH ANOTHER FLT WITH SAME LAST DIGITS. CALLED AND TOLD US TO CLIMB TO PREVIOUS ALT. WE COMPLIED.

Data retrieved from NASA's ASRS site as of August 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.