A320 experiences autoplt pitch over during approach in den airspace.

Attributes
ACN	426933
Time
Date	199901
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : den
State Reference	CO
Altitude	msl bound lower : 7000 msl bound upper : 7000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	A320
Navigation In Use	Other
Route In Use	approach : visual arrival other enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Experience	flight time last 90 days : 150 flight time total : 18000 flight time type : 75
ASRS Report	426933
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial
Events
Anomaly	aircraft equipment problem : critical other anomaly other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : overcame equipment problem flight crew : returned to intended course or assigned course
Consequence	Other
Supplementary
Air Traffic Incident	other

Narrative:

Maneuvering on visual approach using autoplt, on GS at 180 KTS with 7000 ft altitude captured, aircraft suddenly pitched over into 2000 FPM descent. GPWS activated. Captain and first officer simultaneously applied toga thrust to initiate go around and disconnected autoplt. Remainder of approach and landing uneventful. Callback conversation with reporter revealed the following information: the reporter states that no incorrect inputs were made to the autoplt by either pilot, and that the event was not turbulence related. He also states that he has low time in this aircraft (75 hours), and does not have any idea why the pitch-over occurred. He has requested further information from maintenance on their findings, but has heard nothing to date.

Original NASA ASRS Text

Title: A320 EXPERIENCES AUTOPLT PITCH OVER DURING APCH IN DEN AIRSPACE.

Narrative: MANEUVERING ON VISUAL APCH USING AUTOPLT, ON GS AT 180 KTS WITH 7000 FT ALT CAPTURED, ACFT SUDDENLY PITCHED OVER INTO 2000 FPM DSCNT. GPWS ACTIVATED. CAPT AND FO SIMULTANEOUSLY APPLIED TOGA THRUST TO INITIATE GAR AND DISCONNECTED AUTOPLT. REMAINDER OF APCH AND LNDG UNEVENTFUL. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATES THAT NO INCORRECT INPUTS WERE MADE TO THE AUTOPLT BY EITHER PLT, AND THAT THE EVENT WAS NOT TURB RELATED. HE ALSO STATES THAT HE HAS LOW TIME IN THIS ACFT (75 HRS), AND DOES NOT HAVE ANY IDEA WHY THE PITCH-OVER OCCURRED. HE HAS REQUESTED FURTHER INFO FROM MAINT ON THEIR FINDINGS, BUT HAS HEARD NOTHING TO DATE.

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.