Narrative:

Due to reported and actual moderate turbulence at FL370, we requested a lower altitude. Hence, we were told to expect FL330, descend to FL350 and contact memphis on 127.37. The handoff frequency was 126.45. They were to have lower for us. We checked in reporting level at FL350. Next thing you know, center asked us to verify altitude and we confirmed FL350. ATC assigned 'turn 50 degrees right.' we saw TCASII TA, then RA to descend, which we did, and reported to ATC. This was an ATC mix-up, as we both heard FL350 as assigned altitude. There was no confusion for us. In the future, ATC should let the next sector handle our requests entirely if they can't do it themselves, and we as pilots should have queried checking in to a new nonstandard altitude. This had potential to be big headlines.

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Original NASA ASRS Text

Title: ACR FLC INITIATE EVASIVE TCASII MANEUVER AFTER A ZME FREQ CHANGE FOLLOWING AN INTERIM ALT DSCNT THAT IS QUESTIONED BY THE SUCCEEDING ZME CTLR.

Narrative: DUE TO RPTED AND ACTUAL MODERATE TURB AT FL370, WE REQUESTED A LOWER ALT. HENCE, WE WERE TOLD TO EXPECT FL330, DSND TO FL350 AND CONTACT MEMPHIS ON 127.37. THE HDOF FREQ WAS 126.45. THEY WERE TO HAVE LOWER FOR US. WE CHKED IN RPTING LEVEL AT FL350. NEXT THING YOU KNOW, CTR ASKED US TO VERIFY ALT AND WE CONFIRMED FL350. ATC ASSIGNED 'TURN 50 DEGS R.' WE SAW TCASII TA, THEN RA TO DSND, WHICH WE DID, AND RPTED TO ATC. THIS WAS AN ATC MIX-UP, AS WE BOTH HEARD FL350 AS ASSIGNED ALT. THERE WAS NO CONFUSION FOR US. IN THE FUTURE, ATC SHOULD LET THE NEXT SECTOR HANDLE OUR REQUESTS ENTIRELY IF THEY CAN'T DO IT THEMSELVES, AND WE AS PLTS SHOULD HAVE QUERIED CHKING IN TO A NEW NONSTANDARD ALT. THIS HAD POTENTIAL TO BE BIG HEADLINES.

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.