2 ACR ACFT CROSS THROUGH EACH OTHER'S ASSIGNED ALT IN RESPONSE TO A TCASII RA RESULTING IN THE CTLR REISSUING ALT ASSIGNMENT TO THE DSNDING ACFT WHO HAD CLBED INSTEAD OF DSNDING.

Narrative

I GAVE ACR X 'PLT'S DISCRETION TO FL270; EXPECT TO CROSS RIDGY AT FL240.' PLT'S READBACK CORRECT. ACR X WAS NEBOUND ON WARRD4 ARR; DESTINED EWR. ACR Y WAS SWBOUND ON J37 J191 PXT ARGAL2 RDU AT FL260. ACR X STARTED OUT OF HIS CRUISING ALT OF FL370; DSNDING TO FL270. I CALLED TFC VIA MERGING TARGET PROCS PER 7110.65. AS I CALLED THE TFC TO ACR Y; I NOTICED ACR X MODE C AT FL266. BEFORE I COULD QUESTION ACR Y ABOUT HIS ALT; ACR X RESPONDED; 'WE HAVE A TCASII RA; WE'RE DSNDING.' BEFORE; I COULD RESPOND; ACR Y SAID; 'WE HAVE A TCASII RESOLUTION ALSO; WE'RE CLBING!' THE 2 ACFT DSNDED AND CLBED THROUGH EACH OTHER'S ALT; WITHIN 15 DEGS OF BEING HEAD ON. THE NTAP SHOWED THE CLOSEST POINT OF LOSS OF SEPARATION AT APPROX 2.2 MI AND 300 FT. SUPPLEMENTAL INFORMATION FROM ACN 253640: ZDC ADVISED US THAT THERE WAS TFC AT FL270 AT OUR 12-12:30 POS. WE WERE LEVEL AT FL260 AND BEGAN LOOKING FOR THE TFC. NEXT WE RECEIVED A TA ON TCASII. WE WATCHED AS THE TFC WAS CONTINUING A DSCNT THROUGH FL270 AND WAS CLOSING FAST AT OUR 12:30 POS. AT 4 MI WE RECEIVED AN RA TO 'CLB.' TFC WAS NOW 200 FT ABOVE US AND DSNDING. THE CAPT INITIATED THE REQUIRED CLB AS I TOLD THE CTLR OF THE RA AND THAT WE WERE CLBING. SHE (THE CTLR) SAID TO LEVEL OFF AT FL270; AND WE DID. THE OTHER ACFT SAID THEY RECEIVED AN RA AS WELL. WE NEVER VISUALLY COULD SEE OUR TFC BUT ESTIMATE THAT IT PASSED OFF OUR R AT 2 MI AND 1000 FT BELOW US.