Altitude deviation. Altitude overshot on descent.

Attributes
ACN	114149
Time
Date	198906
Day	Sat
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : aqn
State Reference	TX
Altitude	msl bound lower : 10500 msl bound upper : 11000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	artcc : zfw
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other
Flight Phase	descent other
Route In Use	arrival other arrival star : star
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 : 6000 flight time type : 1800
ASRS Report	114149
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : flight engineer pilot : atp pilot : cfi
Experience	flight time last 90 days : 210 flight time total : 16000 flight time type : 210
ASRS Report	114327
Events
Anomaly	aircraft equipment problem : less severe altitude deviation : overshoot non adherence : clearance
Independent Detector	other flight crewa
Resolutory Action	flight crew : overcame equipment problem flight crew : returned to intended course or assigned course
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

Assigned descent clearance to 11,000. Copilot flying aircraft. Approximately 11,100' aircraft still descending (autoplt on) at approximately 100 FPM. I called 'there's eleven'. By the time the copilot reacted got descent stopped and climbed back to 11,000' we descended to 10,500'. Autoplt did not capture altitude set in window. This is yet another case of the medium large transport busting an assigned altitude. The system's design failure to not 'automatic-arm' or 'automatic-rearm' to altitude capture mode is the culprit.

Original NASA ASRS Text

Title: ALT DEVIATION. ALT OVERSHOT ON DESCENT.

Narrative: ASSIGNED DSCNT CLRNC TO 11,000. COPLT FLYING ACFT. APPROX 11,100' ACFT STILL DSNDING (AUTOPLT ON) AT APPROX 100 FPM. I CALLED 'THERE'S ELEVEN'. BY THE TIME THE COPLT REACTED GOT DSCNT STOPPED AND CLIMBED BACK TO 11,000' WE DESCENDED TO 10,500'. AUTOPLT DID NOT CAPTURE ALT SET IN WINDOW. THIS IS YET ANOTHER CASE OF THE MLG BUSTING AN ASSIGNED ALT. THE SYSTEM'S DESIGN FAILURE TO NOT 'AUTO-ARM' OR 'AUTO-REARM' TO ALT CAPTURE MODE IS THE CULPRIT.

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.