Narrative:

Cleared to FL280, while approaching. Controller asked why I ws cleared differently to original clearance. I said I wasn't, he was confused. In the process, I flew past FL280 to FL285. I exceeded my assigned level by 500 ft for a few seconds.

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Original NASA ASRS Text

Title: AN F100 CAPT ADMITTED TO AN ALT BUST WHILE ON APCH TO ELP DURING AN ARGUMENT WITH THE ARTCC CTLR.

Narrative: CLRED TO FL280, WHILE APCHING. CTLR ASKED WHY I WS CLRED DIFFERENTLY TO ORIGINAL CLRNC. I SAID I WASN'T, HE WAS CONFUSED. IN THE PROCESS, I FLEW PAST FL280 TO FL285. I EXCEEDED MY ASSIGNED LEVEL BY 500 FT FOR A FEW SECONDS.

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.