Narrative:

Inbound to atl at 14000', atl approach control asked us if we were descending to 12000' from 14000'. I responded 'negative, we never received a descent to 12000'.' the controller then asked an air carrier flight if he was descending to 12000 from 14000'. The frequency was extremely congested, with almost continuous traffic, and I intended to question the controller on the proper altitude for our flight. After considerable radio traffic, the controller issued us a clearance to 11000'. We reported out of 14000' for 11000. As of this writing, I still don't know what altitude we were assigned when the controller posed his question to us. Had we missed a clearance due to frequency congestion? Did he believe we had taken a descent clearance meant for someone else? When I wished to question my clearance, there was no room to verify because no one could get a word in. Since I had not received a clearance to 12000', I maintained 14000' until the clearance was issued (in proper form) to 11000'. This is clearly another saturated radio frequency problem. I rate this as the #1 ATC problem that I encounter on a regular basis. The controllers are too busy issuing multiple clrncs that verifications (readbacks) are rarely heard and comprehended due to blocked xmissions/controller vol overload. Increased vigilance on assigned frequencys and continued wearing of headsets has done little to reduce this type of problem.

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Original NASA ASRS Text

Title: FREQ CONGESTION PREVENTED FLT CREW OF MLG APCHING ALT FROM CONFIRMING ALT ASSIGNMENT.

Narrative: INBND TO ATL AT 14000', ATL APCH CTL ASKED US IF WE WERE DSNDING TO 12000' FROM 14000'. I RESPONDED 'NEGATIVE, WE NEVER RECEIVED A DSCNT TO 12000'.' THE CTLR THEN ASKED AN ACR FLT IF HE WAS DSNDING TO 12000 FROM 14000'. THE FREQ WAS EXTREMELY CONGESTED, WITH ALMOST CONTINUOUS TFC, AND I INTENDED TO QUESTION THE CTLR ON THE PROPER ALT FOR OUR FLT. AFTER CONSIDERABLE RADIO TFC, THE CTLR ISSUED US A CLRNC TO 11000'. WE RPTED OUT OF 14000' FOR 11000. AS OF THIS WRITING, I STILL DON'T KNOW WHAT ALT WE WERE ASSIGNED WHEN THE CTLR POSED HIS QUESTION TO US. HAD WE MISSED A CLRNC DUE TO FREQ CONGESTION? DID HE BELIEVE WE HAD TAKEN A DSCNT CLRNC MEANT FOR SOMEONE ELSE? WHEN I WISHED TO QUESTION MY CLRNC, THERE WAS NO ROOM TO VERIFY BECAUSE NO ONE COULD GET A WORD IN. SINCE I HAD NOT RECEIVED A CLRNC TO 12000', I MAINTAINED 14000' UNTIL THE CLRNC WAS ISSUED (IN PROPER FORM) TO 11000'. THIS IS CLEARLY ANOTHER SATURATED RADIO FREQ PROBLEM. I RATE THIS AS THE #1 ATC PROB THAT I ENCOUNTER ON A REGULAR BASIS. THE CTLRS ARE TOO BUSY ISSUING MULTIPLE CLRNCS THAT VERIFICATIONS (READBACKS) ARE RARELY HEARD AND COMPREHENDED DUE TO BLOCKED XMISSIONS/CTLR VOL OVERLOAD. INCREASED VIGILANCE ON ASSIGNED FREQS AND CONTINUED WEARING OF HEADSETS HAS DONE LITTLE TO REDUCE THIS TYPE OF PROB.

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.