Altitude deviation altitude excursion - autoplt altitude hold problem.

Attributes
ACN	297718
Time
Date	199502
Day	Mon
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : den
State Reference	CO
Altitude	msl bound lower : 11300 msl bound upper : 12000
Environment
Flight Conditions	IMC
Light	Night
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	cruise other
Route In Use	enroute airway : den
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : cfi pilot : atp pilot : commercial pilot : instrument pilot : flight engineer
Experience	flight time total : 8000 flight time type : 2500
ASRS Report	297718
Person 2
Affiliation	company : air carrier
Function	flight crew : second officer
Qualification	pilot : cfi pilot : atp pilot : instrument pilot : flight engineer
Experience	flight time last 90 days : 230 flight time total : 7000 flight time type : 500
ASRS Report	297719
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : became reoriented flight crew : overcame equipment problem flight crew : returned to intended course or assigned course
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Level 12000 ft altitude hold released and aircraft descended to 11300 ft before recovery was completed. Recovery completed and we climbed back to 12000 ft.

Original NASA ASRS Text

Title: ALTDEV ALT EXCURSION - AUTOPLT ALT HOLD PROB.

Narrative: LEVEL 12000 FT ALT HOLD RELEASED AND ACFT DSNDED TO 11300 FT BEFORE RECOVERY WAS COMPLETED. RECOVERY COMPLETED AND WE CLBED BACK TO 12000 FT.

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.