Narrative:

I was first officer from mgm montgomery, al, to atlanta, GA. The captain was flying and I was performing non-flying duties. On switching to atlanta center on 120.45 was given clearance up to 11000'. I acknowledged and repeated it to the captain. As we passed through 10000', I turned off our landing lights and told the captain I would be on #2 radio to talk to our company, as is our airlines procedure, and that we had one (thousand) to go. I called company on #2 and gave them our times and ETA for atlanta. On switching back to #1 and checking our flight situation, I noticed we were 11300' and climbing. I reached up to bump the yoke and quickly asked the captain our assigned altitude. He said we were cleared to 12. I asked if he was sure because that was unusual and he was unfamiliar with this area. He stated that he was sure. Upon arrival at 12000', center asked our altitude. I answered 12000'. He responded, roger, maintain altitude. This exchange made me question the captain again, and he restated we had been cleared to 12000'. Center said nothing else, and a few mins later gave us a clearance down to 11000' for our arrival in atlanta. Upon landing in atlanta I called center to find out if there had been a problem. I got the area supervisor on the phone, who pulled the strip and said that my suspicious were correct, we were supposed to stop at 11000'. This supervisor told me that there was no other traffic in the area, no conflict, and they planned to take no action. The captain on this flight was a recent upgrade, and seemed weak in several areas. I filed a trip report and talked to my superiors about this occurrence. In retrospect I should have gotten a confirmation despite the fact the captain seemed sure we were cleared to another altitude.

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Original NASA ASRS Text

Title: CAPT OF LTT COMMUTER ACR CLIMBS TO 12000' OVER THE OBJECTIONS OF HIS FO WHO BELIEVED THAT THE FLT HAD ONLY BEEN CLEARED TO 11000'. ATC ISSUED NEW CLRNC BUT FO LATER VERIFIED THAT HIS OWN PERCEPTION WAS CORRECT.

Narrative: I WAS F/O FROM MGM MONTGOMERY, AL, TO ATLANTA, GA. THE CAPT WAS FLYING AND I WAS PERFORMING NON-FLYING DUTIES. ON SWITCHING TO ATLANTA CENTER ON 120.45 WAS GIVEN CLRNC UP TO 11000'. I ACKNOWLEDGED AND REPEATED IT TO THE CAPT. AS WE PASSED THROUGH 10000', I TURNED OFF OUR LNDG LIGHTS AND TOLD THE CAPT I WOULD BE ON #2 RADIO TO TALK TO OUR COMPANY, AS IS OUR AIRLINES PROC, AND THAT WE HAD ONE (THOUSAND) TO GO. I CALLED COMPANY ON #2 AND GAVE THEM OUR TIMES AND ETA FOR ATLANTA. ON SWITCHING BACK TO #1 AND CHKING OUR FLT SITUATION, I NOTICED WE WERE 11300' AND CLBING. I REACHED UP TO BUMP THE YOKE AND QUICKLY ASKED THE CAPT OUR ASSIGNED ALT. HE SAID WE WERE CLRED TO 12. I ASKED IF HE WAS SURE BECAUSE THAT WAS UNUSUAL AND HE WAS UNFAMILIAR WITH THIS AREA. HE STATED THAT HE WAS SURE. UPON ARR AT 12000', CENTER ASKED OUR ALT. I ANSWERED 12000'. HE RESPONDED, ROGER, MAINTAIN ALT. THIS EXCHANGE MADE ME QUESTION THE CAPT AGAIN, AND HE RESTATED WE HAD BEEN CLRED TO 12000'. CENTER SAID NOTHING ELSE, AND A FEW MINS LATER GAVE US A CLRNC DOWN TO 11000' FOR OUR ARR IN ATLANTA. UPON LNDG IN ATLANTA I CALLED CENTER TO FIND OUT IF THERE HAD BEEN A PROB. I GOT THE AREA SUPVR ON THE PHONE, WHO PULLED THE STRIP AND SAID THAT MY SUSPICIOUS WERE CORRECT, WE WERE SUPPOSED TO STOP AT 11000'. THIS SUPVR TOLD ME THAT THERE WAS NO OTHER TFC IN THE AREA, NO CONFLICT, AND THEY PLANNED TO TAKE NO ACTION. THE CAPT ON THIS FLT WAS A RECENT UPGRADE, AND SEEMED WEAK IN SEVERAL AREAS. I FILED A TRIP RPT AND TALKED TO MY SUPERIORS ABOUT THIS OCCURRENCE. IN RETROSPECT I SHOULD HAVE GOTTEN A CONFIRMATION DESPITE THE FACT THE CAPT SEEMED SURE WE WERE CLRED TO ANOTHER ALT.

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.