Narrative:

We were given clearance to cross 25 mi north of mcb at FL280. Somehow I got it in my head to cross mcb at FL280. About 28 DME north of mcb, center asked what our altitude was and a descent was started at that time. No traffic observed on TCASII and no further comment from ATC. A mental block on our part.

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Original NASA ASRS Text

Title: FLC OF A SUPER MD80 FAILED TO DSND TO A XING RESTR ALT DUE TO MISINTERP OF THE CLRNC.

Narrative: WE WERE GIVEN CLRNC TO CROSS 25 MI N OF MCB AT FL280. SOMEHOW I GOT IT IN MY HEAD TO CROSS MCB AT FL280. ABOUT 28 DME N OF MCB, CTR ASKED WHAT OUR ALT WAS AND A DSCNT WAS STARTED AT THAT TIME. NO TFC OBSERVED ON TCASII AND NO FURTHER COMMENT FROM ATC. A MENTAL BLOCK ON OUR PART.

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.