Narrative:

ATC transponder readout. While on blue ridge arrival ATC gave us clearance to cross baton at 11000 ft. We leveled off at 11000 ft 5 mi prior to baton and ATC asked us to verify our altitude as ATC momentarily had our aircraft at 9000 ft. We told him we were level at 11000 ft and resumed the arrival. This is the first time an event like this has occurred to me. Altitude differences of 1-3 hundred ft have occurred but not 2 thousand. I am curious if this is an ATC or aircraft glitch.

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Original NASA ASRS Text

Title: ATC CTLR QUESTIONED FLC OF AN LGT REGARDING THEIR ASSIGNED ALT. READOUT WAS 2000 FT LESS THAN ASSIGNED MOMENTARILY.

Narrative: ATC XPONDER READOUT. WHILE ON BLUE RIDGE ARR ATC GAVE US CLRNC TO CROSS BATON AT 11000 FT. WE LEVELED OFF AT 11000 FT 5 MI PRIOR TO BATON AND ATC ASKED US TO VERIFY OUR ALT AS ATC MOMENTARILY HAD OUR ACFT AT 9000 FT. WE TOLD HIM WE WERE LEVEL AT 11000 FT AND RESUMED THE ARR. THIS IS THE FIRST TIME AN EVENT LIKE THIS HAS OCCURRED TO ME. ALT DIFFERENCES OF 1-3 HUNDRED FT HAVE OCCURRED BUT NOT 2 THOUSAND. I AM CURIOUS IF THIS IS AN ATC OR ACFT GLITCH.

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.