OPERROR OCCURRED WHEN RPTR ISSUED DSCNT CLRNC FOR ACR X TO DSND TO FL240 FROM FL330. ACR Y; SAME COMPANY WITH SIMILAR CALL SIGNS; ACKNOWLEDGED THE READBACK AND BEGAN DSCNT. ACR Y'S DSCNT CONFLICTED WITH ACR Z AT FL310. RPTR ALLEGED THAT DUE TO A FREQ BLEEDTHROUGH; ACR Y CALL SIGNS SOUNDED LIKE ACR X'S. PLTDEV.

Narrative

ACR Z WAS AT FL310 EBOUND AWAITING HIGHER WHEN BY ACR Y THERE WAS 1 NORDO ACFT IN THE SECTOR. SEVERE WX WITH TOPS TO FL410 FROM LIT-CLE. ACR X AT FL330 INBOUND TO IND WAS PUT ON A N HDG TO GET AROUND ACFT IN ORDER TO DSND. ACR Y WAS VECTORED FOR SPACING TO DTW. THERE WERE 4 ACFT (OF THE 16 ON THE SECTOR FREQ AT THE TIME) BEING SPACED TO DTW. THERE WAS A LOT OF FREQ BLEEDTHROUGH ON THE R-SIDE. ACR X WAS ISSUED FL240; ACR Y TOOK THE CLRNC FOR ACR X. ON THE FREQ; IT SOUNDED LIKE ACR X. THE D-SIDE TAPE WAS MUCH CLEARER THAN THE R-SIDE. WHEN THE MODE C ON ACR Y SHOWED BELOW FL330 I INQUIRED AS TO WHAT HE WAS DOING. I THEN CLRED HIM TO CLB IMMEDIATELY TO FL330 AND ISSUED THE TFC BELOW HIM AT FL310; ACR Z. AFTERWARDS; ACR X WAS ISSUED FL240 AND HE SAID HE WAS CONFUSED ABOUT THE EARLIER CLRNC; BUT ELECTED NOT TO SAY ANYTHING. I FEEL THAT IF THE PLT ON ACR X WAS CONFUSED ABOUT THE CLRNC; THEN IT WAS INEXCUSABLE OF HIM TO SAY NOTHING. THE PLT ON ACR Y SHOULD HAVE PAID CLOSER ATTN AND NOT TAKEN THE CLRNC FOR SOMEONE ELSE. THE LOUSY FREQ EQUIP WAS A CONTRIBUTING FACTOR. SUPPLEMENTAL INFO FROM ACN 337488: 2 FACTORS THAT COME INTO THE PICTURE ARE THE SIMILAR SOUNDING CALL SIGNS AND THE CLARITY OF THE CTL FREQS. THE CTL FREQS WERE USABLE; BUT WITH NEW EQUIP HOW MUCH CLEARER WOULD THE READBACK HAVE BEEN? THE SIMILAR SOUNDING CALL SIGNS WERE TURNED INTO THE TFC MGMNT UNIT TO CONTACT THE COMPANY ABOUT A CHANGE OF CALL SIGN.