Narrative:

Aircraft Y was non radar at FL180 and given holding instructions to hold at etl at 17000 ft and efc XX30 UTC. Aircraft X had a radio that buzzed loudly every time he keyed and words can only be heard faintly if you listened closely. I couldn't tell for certain when he called in, but issued a holding clearance to aircraft X to hold at etl and maintain FL200 and to efc XX45. I heard distinctly (because I was concentrating on a readback) that aircraft X acknowledged the holding instructions and wanted to go direct tex with intentions to cancel IFR. I told aircraft X that 3 aircraft are in front of him for approach into tex. Then I got busy with many ase arrs (aspen, co). Aircraft X tried to contact me several times with request to go VFR. He was in such a position that I couldn't descend him to FL180 due to traffic aircraft Y. I couldn't even be sure what aircraft X was saying because his radio was unreadable. I ignored aircraft X because more important work was trying to get 4 aircraft into ase. When I looked back at tex, aircraft X had lost radar acquisition. Aircraft X had turned off his transponder and went into tex VFR without a clearance and through aircraft Y.

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Original NASA ASRS Text

Title: RPT OF SW2 FLC ALLEGEDLY TURNING OFF THE XPONDER, EXITING THE HOLDING FIX AND DSNDING FROM FL200 THROUGH THE PCA WITHOUT CLRNC AND SEPARATION WITH OTHER HOLDING TFC FOR A SUBSEQUENT VFR APCH TO TEX.

Narrative: ACFT Y WAS NON RADAR AT FL180 AND GIVEN HOLDING INSTRUCTIONS TO HOLD AT ETL AT 17000 FT AND EFC XX30 UTC. ACFT X HAD A RADIO THAT BUZZED LOUDLY EVERY TIME HE KEYED AND WORDS CAN ONLY BE HEARD FAINTLY IF YOU LISTENED CLOSELY. I COULDN'T TELL FOR CERTAIN WHEN HE CALLED IN, BUT ISSUED A HOLDING CLRNC TO ACFT X TO HOLD AT ETL AND MAINTAIN FL200 AND TO EFC XX45. I HEARD DISTINCTLY (BECAUSE I WAS CONCENTRATING ON A READBACK) THAT ACFT X ACKNOWLEDGED THE HOLDING INSTRUCTIONS AND WANTED TO GO DIRECT TEX WITH INTENTIONS TO CANCEL IFR. I TOLD ACFT X THAT 3 ACFT ARE IN FRONT OF HIM FOR APCH INTO TEX. THEN I GOT BUSY WITH MANY ASE ARRS (ASPEN, CO). ACFT X TRIED TO CONTACT ME SEVERAL TIMES WITH REQUEST TO GO VFR. HE WAS IN SUCH A POS THAT I COULDN'T DSND HIM TO FL180 DUE TO TFC ACFT Y. I COULDN'T EVEN BE SURE WHAT ACFT X WAS SAYING BECAUSE HIS RADIO WAS UNREADABLE. I IGNORED ACFT X BECAUSE MORE IMPORTANT WORK WAS TRYING TO GET 4 ACFT INTO ASE. WHEN I LOOKED BACK AT TEX, ACFT X HAD LOST RADAR ACQUISITION. ACFT X HAD TURNED OFF HIS XPONDER AND WENT INTO TEX VFR WITHOUT A CLRNC AND THROUGH ACFT Y.

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.