An air carrier large transport descended through its assigned altitude. Error admitted.

Attributes
ACN	355123
Time
Date	199612
Day	Mon
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : jvl
State Reference	WI
Altitude	msl bound lower : 23700 msl bound upper : 24000
Environment
Flight Conditions	IMC
Light	Night
Aircraft 1
Controlling Facilities	artcc : zau
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	descent other
Route In Use	enroute : direct
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 150 flight time total : 9000 flight time type : 1000
ASRS Report	355123
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 150 flight time total : 11000 flight time type : 2400
ASRS Report	354980
Events
Anomaly	altitude deviation : overshoot non adherence : clearance other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course flight crew : became reoriented
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Aircraft cleared to descend to FL240. There were numerous distrs in the cockpit due to flight engineer chkout as well as flight engineer check pilot also being trained. Aircraft descended to FL237. Immediate action was taken to return to FL240. No conflicts arose with other aircraft.

Original NASA ASRS Text

Title: AN ACR LGT DSNDED THROUGH ITS ASSIGNED ALT. ERROR ADMITTED.

Narrative: ACFT CLRED TO DSND TO FL240. THERE WERE NUMEROUS DISTRS IN THE COCKPIT DUE TO FE CHKOUT AS WELL AS FE CHK PLT ALSO BEING TRAINED. ACFT DSNDED TO FL237. IMMEDIATE ACTION WAS TAKEN TO RETURN TO FL240. NO CONFLICTS AROSE WITH OTHER ACFT.

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.