Narrative:

During climb out from msy to den, we were cleared to FL350, approaching aex, we received clearance from ATC to deviate for WX. ATC suggested and we advised we would fly a 300 degree heading. Soon thereafter, we were given a frequency change to ZHU. I dialed in the frequency, but never switched it from the standby due to distrs from the approaching WX. The captain was on the interphone to advise the flight attendants to be seated and I was busy working the radar. We elected to change our course to the north to deviate around WX and advised ATC. At that point we were told we were on the wrong frequency and to stand by for a new frequency. As we turned north, I noticed a target on TCASII at FL350 that was a potential threat. The captain and I observed the threat to be closing and queried ATC. We were still on the frequency that told us to stand by for a new one and I advised her of the target. We had already elected to turn back towards the west. Controller told us to level at FL330. We were approaching FL340 and so initiated a descent to FL330. Finally, we were given the new frequency and checked in with ZHU. ZHU told us to disregard the descent and continue climb to FL350. We never received a TCASII of any kind, but we saw the target visually and estimated closest point of approach at approximately 8 mi. TCASII showed our altitudes at 1000 ft apart at closest point of approach. ATC made no note of the incident.

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Original NASA ASRS Text

Title: DISTR BY WX DEVS, A FLC NEGLECTS TO CHANGE FREQ WHEN IT WAS ISSUED RESULTING IN A TFC CONFLICT.

Narrative: DURING CLBOUT FROM MSY TO DEN, WE WERE CLRED TO FL350, APCHING AEX, WE RECEIVED CLRNC FROM ATC TO DEVIATE FOR WX. ATC SUGGESTED AND WE ADVISED WE WOULD FLY A 300 DEG HDG. SOON THEREAFTER, WE WERE GIVEN A FREQ CHANGE TO ZHU. I DIALED IN THE FREQ, BUT NEVER SWITCHED IT FROM THE STANDBY DUE TO DISTRS FROM THE APCHING WX. THE CAPT WAS ON THE INTERPHONE TO ADVISE THE FLT ATTENDANTS TO BE SEATED AND I WAS BUSY WORKING THE RADAR. WE ELECTED TO CHANGE OUR COURSE TO THE N TO DEVIATE AROUND WX AND ADVISED ATC. AT THAT POINT WE WERE TOLD WE WERE ON THE WRONG FREQ AND TO STAND BY FOR A NEW FREQ. AS WE TURNED N, I NOTICED A TARGET ON TCASII AT FL350 THAT WAS A POTENTIAL THREAT. THE CAPT AND I OBSERVED THE THREAT TO BE CLOSING AND QUERIED ATC. WE WERE STILL ON THE FREQ THAT TOLD US TO STAND BY FOR A NEW ONE AND I ADVISED HER OF THE TARGET. WE HAD ALREADY ELECTED TO TURN BACK TOWARDS THE W. CTLR TOLD US TO LEVEL AT FL330. WE WERE APCHING FL340 AND SO INITIATED A DSCNT TO FL330. FINALLY, WE WERE GIVEN THE NEW FREQ AND CHKED IN WITH ZHU. ZHU TOLD US TO DISREGARD THE DSCNT AND CONTINUE CLB TO FL350. WE NEVER RECEIVED A TCASII OF ANY KIND, BUT WE SAW THE TARGET VISUALLY AND ESTIMATED CLOSEST POINT OF APCH AT APPROX 8 MI. TCASII SHOWED OUR ALTS AT 1000 FT APART AT CLOSEST POINT OF APCH. ATC MADE NO NOTE OF THE INCIDENT.

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.