Narrative:

During cruise at FL370, we were given a descent to a lower altitude which we thought was FL310 and which we had set and confirmed in the altitude window. Apparently, our assigned altitude was FL330. I was communicating with first flight attendant on the intercom when the captain initiated a climb as advised by the controller. Next moment we received an RA to descend. The captain complied with the RA. A few moments later, the controller advised us to turn right sharply. At the same time we made visual contact with the traffic and were able to maintain separation. I believe the opposing instructions from the controller and TCASII further aggravated the situation. An initial instruction to turn would have avoided the controller/TCASII conflict. I am, with this, not putting any blame on the controller. Supplemental information from acn 575368: about 150 mi west of elp, center gave us a clearance to descend to what I believed to be FL310. I dialed FL310 into the altitude alerter and verified with the PNF. He agreed. Passing around FL318, the controller asked our assigned altitude. I said FL310. He said to climb to FL330. I initiated the climb, disconnected the autoplt, and climbed at a rate of over 2000 FPM. After several seconds, the TCASII stated, 'traffic, descend.' I immediately stopped descent and saw the other aircraft pass off our right about 1 1/2 mi and 500 ft. I called the controller on the ground and he said he listened to the tapes and our readback was actually FL330. And we were given a frequency change, which we never checked in on. The flight attendant had just called as we started the descent and the PNF answered her on the interphone. I feel we procedurally were correct. I verified with the first officer the altitude, however, he either wasn't paying attention or actually thought we were cleared to FL310.

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Original NASA ASRS Text

Title: DURING AN ENRTE ALT CHANGE, A POTENTIAL CONFLICT WITH REDUCED CLRNC OCCURS REQUIRING A DSCNT AND TURN BY FLT X AT OR NEAR FL320, OPPOSITE DIRECTION TFC CONFLICT 115 NM W OF ELP, TX.

Narrative: DURING CRUISE AT FL370, WE WERE GIVEN A DSCNT TO A LOWER ALT WHICH WE THOUGHT WAS FL310 AND WHICH WE HAD SET AND CONFIRMED IN THE ALT WINDOW. APPARENTLY, OUR ASSIGNED ALT WAS FL330. I WAS COMMUNICATING WITH FIRST FLT ATTENDANT ON THE INTERCOM WHEN THE CAPT INITIATED A CLB AS ADVISED BY THE CTLR. NEXT MOMENT WE RECEIVED AN RA TO DSND. THE CAPT COMPLIED WITH THE RA. A FEW MOMENTS LATER, THE CTLR ADVISED US TO TURN R SHARPLY. AT THE SAME TIME WE MADE VISUAL CONTACT WITH THE TFC AND WERE ABLE TO MAINTAIN SEPARATION. I BELIEVE THE OPPOSING INSTRUCTIONS FROM THE CTLR AND TCASII FURTHER AGGRAVATED THE SIT. AN INITIAL INSTRUCTION TO TURN WOULD HAVE AVOIDED THE CTLR/TCASII CONFLICT. I AM, WITH THIS, NOT PUTTING ANY BLAME ON THE CTLR. SUPPLEMENTAL INFO FROM ACN 575368: ABOUT 150 MI W OF ELP, CTR GAVE US A CLRNC TO DSND TO WHAT I BELIEVED TO BE FL310. I DIALED FL310 INTO THE ALT ALERTER AND VERIFIED WITH THE PNF. HE AGREED. PASSING AROUND FL318, THE CTLR ASKED OUR ASSIGNED ALT. I SAID FL310. HE SAID TO CLB TO FL330. I INITIATED THE CLB, DISCONNECTED THE AUTOPLT, AND CLBED AT A RATE OF OVER 2000 FPM. AFTER SEVERAL SECONDS, THE TCASII STATED, 'TFC, DSND.' I IMMEDIATELY STOPPED DSCNT AND SAW THE OTHER ACFT PASS OFF OUR R ABOUT 1 1/2 MI AND 500 FT. I CALLED THE CTLR ON THE GND AND HE SAID HE LISTENED TO THE TAPES AND OUR READBACK WAS ACTUALLY FL330. AND WE WERE GIVEN A FREQ CHANGE, WHICH WE NEVER CHKED IN ON. THE FLT ATTENDANT HAD JUST CALLED AS WE STARTED THE DSCNT AND THE PNF ANSWERED HER ON THE INTERPHONE. I FEEL WE PROCEDURALLY WERE CORRECT. I VERIFIED WITH THE FO THE ALT, HOWEVER, HE EITHER WASN'T PAYING ATTN OR ACTUALLY THOUGHT WE WERE CLRED TO FL310.

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.