Large transport descends to 10,000', ATC contends the flight was only cleared to 11,000'.

Attributes
ACN	119815
Time
Date	198908
Day	Sun
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : sju
State Reference	PR
Altitude	msl bound lower : 10000 msl bound upper : 11000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : mjzs
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	descent other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 210 flight time total : 18000 flight time type : 3000
ASRS Report	119815
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	altitude deviation : overshoot other anomaly other
Independent Detector	other controllera
Resolutory Action	none taken : detected after the fact
Consequence	Other
Supplementary
Primary Problem	Ambiguous
Air Traffic Incident	other

Narrative:

Flight was cleared to descend to 10,000' by center. When we reached that altitude, center informed us that the clearance altitude was 11,000'. There was no problems but still the confusion was there.

Original NASA ASRS Text

Title: LGT DESCENDS TO 10,000', ATC CONTENDS THE FLT WAS ONLY CLEARED TO 11,000'.

Narrative: FLT WAS CLRED TO DSND TO 10,000' BY CENTER. WHEN WE REACHED THAT ALT, CENTER INFORMED US THAT THE CLRNC ALT WAS 11,000'. THERE WAS NO PROBLEMS BUT STILL THE CONFUSION WAS THERE.

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.