CLRNC CONFUSION CAUSES ALTDEV RESULTING IN TCASII RA.

Narrative

I WAS CAPT ON FLT FROM DAB TO EWR. IT WAS THE FO'S LEG AND I WAS HANDLING THE RADIO AND ASSOCIATED DUTIES. WE WERE CRUISING AT FL370. I SWITCHED OFF THE ZDC RADIO TO COPY THE ATIS; CALL THE COMPANY FOR GATE INFO; AND MAKE A PA TO THE PAX. THE FO TOOK OVER CTR COM. SHORTLY AFTER I LEFT THE FREQ; I OBSERVED THE FO RESET THE ALT ALERTER TO FL240 AND START A DSCNT. AS WE PASSED APPROX FL270; I HEARD THE TCASII CALL 'TFC; TFC.' I WAS STILL OFF THE FREQ; BUT I LOOKED AT THE SCOPE AND NOTED TFC AT ABOUT 2 O'CLOCK. WE GOT AN RA ABOUT THAT TIME WHICH COMMANDED A DSCNT. AS WE WERE ALREADY IN A 3500 FPM DSCNT TO FL240 WE CONTINUED THE DSCNT. AT THAT TIME; I GOT A VISUAL ON THE TFC AT 2-3 O'CLOCK HIGH. I ASKED THE FO WHAT HAD HAPPENED. HE STATED THAT WE HAD BEEN CLRED PLT'S DISCRETION TO FL260 TO CROSS RIDGY INTXN AT FL240. ABOUT THEN ZDC CALLED TO TELL US TO CALL ZDC QUALITY ASSURANCE THE NEXT WORK DAY. WHEN I CALLED; I TALKED TO MS. X. SHE SAID THAT; ACCORDING TO THE TAPES; WE HAD BEEN CLRED TO FL260; TO EXPECT RIDGY AT 240. I TALKED TO THE FO AGAIN. HE SWEARS THAT HE HEARD 'PLT'S DISCRETION TO 260; AND CROSS RIDGY AT 240;' (NO MENTION OF XING TFC); AND THAT IS WHAT HE READ BACK. MS. X TELLS ME THAT IS NOT WHAT IS ON THE TAPE. I CANNOT CONFIRM OR DENY ANY OF THIS SINCE I WAS OFF THE FREQ THROUGH THE WHOLE THING. UNFORTUNATELY; SINCE ZDC DID NOT SAY ANYTHING ABOUT DEVIATING FROM A CLRNC WE THOUGHT THE PHONE CALL ONLY HAD TO DO WITH THE TCASII STUDY; SO WE DIDN'T SAVE ANY PAPERWORK; COCKPIT VOICE RECORDER TAPES OR ANYTHING. MS. X INFORMED ME 3 DAYS LATER THAT WE HAD DEVIATED FROM A CLRNC; AND THAT THEY WERE SENDING THE TAPES TO THE FSDO FOR PROCESSING.