Air carrier medium large transport altitude deviation overshot using autoplt automatic-throttles.

Attributes
ACN	120387
Time
Date	198908
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : atl
State Reference	GA
Altitude	msl bound lower : 14000 msl bound upper : 14250
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : atl tower : lax
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 210 flight time type : 600
ASRS Report	120387
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	aircraft equipment problem : less severe altitude deviation : overshoot
Independent Detector	other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

At 13000' MSL climbing to 14000', first officer called, '1 to go, armed' (autoplt, automatic-throttlers were engaged in IAS and EPR limit). DFGS reverted to vertical speed at 3300 FPM climb with full climb EPR going through 13500' and 'arm' for altitude capture dropped out. Pilot disengaged autoplt, automatic-throttle, leveled off and reduced power to idle. Climb stopped at 14250'. Type medium large transport DFGS needs software improvements!!!

Original NASA ASRS Text

Title: ACR MLG ALT DEVIATION OVERSHOT USING AUTOPLT AUTO-THROTTLES.

Narrative: AT 13000' MSL CLBING TO 14000', F/O CALLED, '1 TO GO, ARMED' (AUTOPLT, AUTO-THROTTLERS WERE ENGAGED IN IAS AND EPR LIMIT). DFGS REVERTED TO VERT SPD AT 3300 FPM CLB WITH FULL CLB EPR GOING THROUGH 13500' AND 'ARM' FOR ALT CAPTURE DROPPED OUT. PLT DISENGAGED AUTOPLT, AUTO-THROTTLE, LEVELED OFF AND REDUCED PWR TO IDLE. CLB STOPPED AT 14250'. TYPE MLG DFGS NEEDS SOFTWARE IMPROVEMENTS!!!

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.