MD80 flight crew had an altitude deviation in bwi class east airspace.

Attributes
ACN	512590
Time
Date	200105
Day	Fri
Local Time Of Day	1801 To 2400
Place
Locale Reference	navaid : emi.vortac
State Reference	MD
Altitude	msl bound lower : 10500 msl bound upper : 11000
Environment
Light	Night
Aircraft 1
Controlling Facilities	tracon : d10.tracon
Operator	common carrier : air carrier
Make Model Name	MD-80 Super 80
Flight Phase	descent : intermediate altitude
Route In Use	arrival star : westminster 3
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	512590
Events
Anomaly	altitude deviation : overshoot non adherence : clearance non adherence : far non adherence : published procedure non adherence : company policies other anomaly other
Resolutory Action	controller : issued alert flight crew : returned to assigned altitude
Consequence	other
Supplementary
Problem Areas	ATC Human Performance Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Altitude deviation. While on the westminster 3 arrival into bwi, the controller gave us an altitude and airspeed. We thought he gave us 250 KTS and 5000 ft. Passing 10500 ft, we queried the controller about the altitude and he said we were only cleared to 11000 ft. We immediately climbed back to 11000 ft and leveled off. No known traffic conflicts were noted.

Original NASA ASRS Text

Title: MD80 FLT CREW HAD AN ALTDEV IN BWI CLASS E AIRSPACE.

Narrative: ALTDEV. WHILE ON THE WESTMINSTER 3 ARR INTO BWI, THE CTLR GAVE US AN ALT AND AIRSPD. WE THOUGHT HE GAVE US 250 KTS AND 5000 FT. PASSING 10500 FT, WE QUERIED THE CTLR ABOUT THE ALT AND HE SAID WE WERE ONLY CLRED TO 11000 FT. WE IMMEDIATELY CLBED BACK TO 11000 FT AND LEVELED OFF. NO KNOWN TFC CONFLICTS WERE NOTED.

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.