Narrative:

During departure climb, air carrier X was cleared from 10000 ft to 12000 ft. It was a hectic time during departure. Normally departure control acknowledges our takeoff by 2500 ft MSL but this time they did not acknowledge until approximately 4000 ft MSL. Controller was busy with bad WX, several aircraft requesting WX avoidance vectors, and an air carrier Y flight that had trouble understanding instructions. During the climb to 12000 ft MSL, I queried the controller about what sounded like a further clearance to 14000 ft MSL. Departure said we were not cleared to 14000 ft MSL and should return to 10000 ft MSL(?). We immediately complied and returned out of 11000 ft to 10000 ft MSL. Later, after being reclred to 14000 ft MSL, and before leaving the frequency, and after the captain asked for clarification as to what had happened earlier, the new controller (there was a controller change after the confusion) explained the WX and heavy traffic may have caused some confusion and that, anyway, there had been no danger and therefore 'no problem' with the altitude changes on departure. Remainder of departure and flight were uneventful.

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Original NASA ASRS Text

Title: AFTER FLC OF AN ACR MLG WAS GIVEN A CLRNC TO A HIGHER ALT, DEP CTLR ADVISED THAT SUCH A CLRNC HAD NOT BEEN GIVEN DURING THEIR CLB AND FOR THEM TO RETURN TO THEIR ORIGINAL ALT. WHEN THE FLC QUERIED ATC, ANOTHER CTLR SAID THAT THERE HAD BEEN CTLR CONFUSION DUE TO WX AND HVY TFC, AND THAT THERE HAD BEEN NO CONFLICT WITH RPTR'S FLT.

Narrative: DURING DEP CLB, ACR X WAS CLRED FROM 10000 FT TO 12000 FT. IT WAS A HECTIC TIME DURING DEP. NORMALLY DEP CTL ACKNOWLEDGES OUR TKOF BY 2500 FT MSL BUT THIS TIME THEY DID NOT ACKNOWLEDGE UNTIL APPROX 4000 FT MSL. CTLR WAS BUSY WITH BAD WX, SEVERAL ACFT REQUESTING WX AVOIDANCE VECTORS, AND AN ACR Y FLT THAT HAD TROUBLE UNDERSTANDING INSTRUCTIONS. DURING THE CLB TO 12000 FT MSL, I QUERIED THE CTLR ABOUT WHAT SOUNDED LIKE A FURTHER CLRNC TO 14000 FT MSL. DEP SAID WE WERE NOT CLRED TO 14000 FT MSL AND SHOULD RETURN TO 10000 FT MSL(?). WE IMMEDIATELY COMPLIED AND RETURNED OUT OF 11000 FT TO 10000 FT MSL. LATER, AFTER BEING RECLRED TO 14000 FT MSL, AND BEFORE LEAVING THE FREQ, AND AFTER THE CAPT ASKED FOR CLARIFICATION AS TO WHAT HAD HAPPENED EARLIER, THE NEW CTLR (THERE WAS A CTLR CHANGE AFTER THE CONFUSION) EXPLAINED THE WX AND HVY TFC MAY HAVE CAUSED SOME CONFUSION AND THAT, ANYWAY, THERE HAD BEEN NO DANGER AND THEREFORE 'NO PROB' WITH THE ALT CHANGES ON DEP. REMAINDER OF DEP AND FLT WERE UNEVENTFUL.

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.