Mdt alleged to have descended to wrong altitude.

Attributes
ACN	308650
Time
Date	199506
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : sbi
State Reference	TX
Altitude	msl bound lower : 10000 msl bound upper : 12000
Environment
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zhu
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	other : unknown
Flight Phase	descent other
Flight Plan	VFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : atp pilot : commercial pilot : instrument
Experience	flight time last 90 days : 220 flight time total : 20800
ASRS Report	308650
Person 2
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Events
Anomaly	altitude deviation : overshoot other anomaly other
Independent Detector	other controllera
Resolutory Action	none taken : anomaly accepted
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Ambiguous
Air Traffic Incident	other

Narrative:

During cruise flight I was given a descent instruction that was unclr (partially blurred?) I asked the center to repeat the new altitude and then readback and wrote down '10000.' passing (downwind) through 11000 ft the controller asked for my altitude. I said '11,' and the controller said I was only cleared to 12. (I don't know if it was a 'hearback' problem on the part of the controller or on my part -- but I am sure that I both wrote down and readback '10'). No other airplane was involved and safety was not breached but now I've been involved in a communication error of some sort.

Original NASA ASRS Text

Title: MDT ALLEGED TO HAVE DSNDED TO WRONG ALT.

Narrative: DURING CRUISE FLT I WAS GIVEN A DSCNT INSTRUCTION THAT WAS UNCLR (PARTIALLY BLURRED?) I ASKED THE CTR TO REPEAT THE NEW ALT AND THEN READBACK AND WROTE DOWN '10000.' PASSING (DOWNWIND) THROUGH 11000 FT THE CTLR ASKED FOR MY ALT. I SAID '11,' AND THE CTLR SAID I WAS ONLY CLRED TO 12. (I DON'T KNOW IF IT WAS A 'HEARBACK' PROB ON THE PART OF THE CTLR OR ON MY PART -- BUT I AM SURE THAT I BOTH WROTE DOWN AND READBACK '10'). NO OTHER AIRPLANE WAS INVOLVED AND SAFETY WAS NOT BREACHED BUT NOW I'VE BEEN INVOLVED IN A COM ERROR OF SOME SORT.

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.