MD10 flight crew has an altitude deviation while en route.

Attributes
ACN	703769
Time
Date	200607
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : mlf.vortac
State Reference	UT
Altitude	msl single value : 34000
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zlc.artcc tower : zzz.tower
Operator	common carrier : air carrier
Make Model Name	MD-10 Conversion
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 100 flight time total : 15000 flight time type : 1200
ASRS Report	703769
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance
Independent Detector	other controllera
Resolutory Action	controller : issued advisory flight crew : returned to assigned altitude
Supplementary
Problem Areas	Weather Aircraft Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

We were deviating around multiple cloud build-ups with the ok from ZLC. After getting clear of all clouds; ZLC asked us to confirm level at FL340. We then noticed our altitude was 400+ ft high. We immediately corrected to FL340.

Original NASA ASRS Text

Title: MD10 FLT CREW HAS AN ALTDEV WHILE ENRTE.

Narrative: WE WERE DEVIATING AROUND MULTIPLE CLOUD BUILD-UPS WITH THE OK FROM ZLC. AFTER GETTING CLR OF ALL CLOUDS; ZLC ASKED US TO CONFIRM LEVEL AT FL340. WE THEN NOTICED OUR ALT WAS 400+ FT HIGH. WE IMMEDIATELY CORRECTED TO FL340.

Data retrieved from NASA's ASRS site as of January 2009 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.