Narrative:

Flight was from phl to bos. Interim level off at 10,000' northeast of acy, over water. Flying on assigned heading (030 degree approximately). Controller issued instructions. We turned to 060 degree to intercept J225 and climbed to FL250. Approximately 5 min after level off, the controller sent us over to the next controller and we checked in. Shortly afterwards, this next controller asked us to confirm our altitude. He stated that FL250 was no problem but wondered if the previous controller had cleared us to this altitude. We replied 'affirmative'. Since we were heading easterly, I thought we were at the correct altitude. The next sector controller also inquired about our altitude. At that point, the first officer and I began to question ourselves. Reflecting back, we both felt that we had been cleared only to FL240. However, we're not absolutely sure since the original controller did not question our level off at FL250. I believe the instructions to intercept J225 and climb to FL240 along with an additional heading instruction was misconstrued and 25,000' was dialed into the cockpit altitude window. Apparently there was no conflict problem because none of the controllers seemed alarmed and, in fact, stated there was no problem. In my case, I feel fatigue was a factor. I'm on reserve status and I received a late evening call for an am show. I retired at approximately late evening and got up at early am. During this short night, my wife was actively sick (vomiting) and my 1 yr old baby had a fever and woke up crying. The first officer was also called late, got up at am and felt he too was fatigued. Perhaps the original controller was also fatigued and so missed out altitude readout.

Related reports:

Google
 

Original NASA ASRS Text

Title: FLT APPARENTLY CRUISING AT WRONG ALT. QUESTIONED BY SEVERAL CTLRS, BUT NEVER REASSIGNED OR TOLD TO CORRECT SO NOT SURE IF WRONG OR NOT.

Narrative: FLT WAS FROM PHL TO BOS. INTERIM LEVEL OFF AT 10,000' NE OF ACY, OVER WATER. FLYING ON ASSIGNED HDG (030 DEG APPROX). CTLR ISSUED INSTRUCTIONS. WE TURNED TO 060 DEG TO INTERCEPT J225 AND CLIMBED TO FL250. APPROX 5 MIN AFTER LEVEL OFF, THE CTLR SENT US OVER TO THE NEXT CTLR AND WE CHECKED IN. SHORTLY AFTERWARDS, THIS NEXT CTLR ASKED US TO CONFIRM OUR ALT. HE STATED THAT FL250 WAS NO PROBLEM BUT WONDERED IF THE PREVIOUS CTLR HAD CLRED US TO THIS ALT. WE REPLIED 'AFFIRMATIVE'. SINCE WE WERE HDG EASTERLY, I THOUGHT WE WERE AT THE CORRECT ALT. THE NEXT SECTOR CTLR ALSO INQUIRED ABOUT OUR ALT. AT THAT POINT, THE F/O AND I BEGAN TO QUESTION OURSELVES. REFLECTING BACK, WE BOTH FELT THAT WE HAD BEEN CLRED ONLY TO FL240. HOWEVER, WE'RE NOT ABSOLUTELY SURE SINCE THE ORIGINAL CTLR DID NOT QUESTION OUR LEVEL OFF AT FL250. I BELIEVE THE INSTRUCTIONS TO INTERCEPT J225 AND CLIMB TO FL240 ALONG WITH AN ADDITIONAL HDG INSTRUCTION WAS MISCONSTRUED AND 25,000' WAS DIALED INTO THE COCKPIT ALT WINDOW. APPARENTLY THERE WAS NO CONFLICT PROBLEM BECAUSE NONE OF THE CTLRS SEEMED ALARMED AND, IN FACT, STATED THERE WAS NO PROBLEM. IN MY CASE, I FEEL FATIGUE WAS A FACTOR. I'M ON RESERVE STATUS AND I RECEIVED A LATE EVENING CALL FOR AN AM SHOW. I RETIRED AT APPROX LATE EVENING AND GOT UP AT EARLY AM. DURING THIS SHORT NIGHT, MY WIFE WAS ACTIVELY SICK (VOMITING) AND MY 1 YR OLD BABY HAD A FEVER AND WOKE UP CRYING. THE F/O WAS ALSO CALLED LATE, GOT UP AT AM AND FELT HE TOO WAS FATIGUED. PERHAPS THE ORIGINAL CTLR WAS ALSO FATIGUED AND SO MISSED OUT ALT READOUT.

Data retrieved from NASA's ASRS site as of August 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.