Narrative:

The first officer was flying the leg. We were descending into phx. I left the frequency to give the required descent announcement to the passenger and flight attendants. When I returned we were passing 12000 for the 11000 set in the altitude window by the first officer. I asked for a 10 degree turn for WX and turned on the anti-ice. As we approached 11200, the approach controller on 128.65 told us to level at 12000. We immediately climbed to 12000 ft on my order. I mentioned to the controller we were cleared to 11000 after reconfirming with the first officer. We were on frequency approximately 3-4 mins and no more was said by the controller. We were sent to 126.6 (final) with a normal to me of voice as if there were no problem. I questioned the first officer extensively on what had occurred. He was very confident we had been cleared to 11000 feet, no uncertainty in his mind. I had assumed, since nothing more was said by the controller, that the controller had made an error and no more would come of it. The next time I knew anything was being done about it was, by coincidence, 3 days later. I checked my mailbox on a day off and found a handwritten, unsigned note to call...at abq center. I normally would not have been at my mailbox for another week. I felt we had plenty of time at the time of occurrence for the controller to mention any follow-on action. This gave me no opportunity to save the aircraft tapes or to write down the occurrence while it was fresh in my mind.

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Original NASA ASRS Text

Title: LGT DSNDING, THOUGHT CLRED TO 11000 WHICH IS UNUSUAL FOR THIS APCH. CTLR REQUESTS LEVEL AT 12000. 3 DAYS LATER, RECEIVES NOTE IN BOX TO CALL CTR.

Narrative: THE FO WAS FLYING THE LEG. WE WERE DSNDING INTO PHX. I LEFT THE FREQ TO GIVE THE REQUIRED DSCNT ANNOUNCEMENT TO THE PAX AND FLT ATTENDANTS. WHEN I RETURNED WE WERE PASSING 12000 FOR THE 11000 SET IN THE ALT WINDOW BY THE FO. I ASKED FOR A 10 DEG TURN FOR WX AND TURNED ON THE ANTI-ICE. AS WE APCHED 11200, THE APCH CTLR ON 128.65 TOLD US TO LEVEL AT 12000. WE IMMEDIATELY CLBED TO 12000 FT ON MY ORDER. I MENTIONED TO THE CTLR WE WERE CLRED TO 11000 AFTER RECONFIRMING WITH THE FO. WE WERE ON FREQ APPROX 3-4 MINS AND NO MORE WAS SAID BY THE CTLR. WE WERE SENT TO 126.6 (FINAL) WITH A NORMAL TO ME OF VOICE AS IF THERE WERE NO PROBLEM. I QUESTIONED THE FO EXTENSIVELY ON WHAT HAD OCCURRED. HE WAS VERY CONFIDENT WE HAD BEEN CLRED TO 11000 FEET, NO UNCERTAINTY IN HIS MIND. I HAD ASSUMED, SINCE NOTHING MORE WAS SAID BY THE CTLR, THAT THE CTLR HAD MADE AN ERROR AND NO MORE WOULD COME OF IT. THE NEXT TIME I KNEW ANYTHING WAS BEING DONE ABOUT IT WAS, BY COINCIDENCE, 3 DAYS LATER. I CHKED MY MAILBOX ON A DAY OFF AND FOUND A HANDWRITTEN, UNSIGNED NOTE TO CALL...AT ABQ CTR. I NORMALLY WOULD NOT HAVE BEEN AT MY MAILBOX FOR ANOTHER WK. I FELT WE HAD PLENTY OF TIME AT THE TIME OF OCCURRENCE FOR THE CTLR TO MENTION ANY FOLLOW-ON ACTION. THIS GAVE ME NO OPPORTUNITY TO SAVE THE ACFT TAPES OR TO WRITE DOWN THE OCCURRENCE WHILE IT WAS FRESH IN MY MIND.

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.