B727 crew experienced an abrupt nose up pitch during cruise.

Attributes
ACN	499710
Time
Date	200101
Day	Wed
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : ind.airport
State Reference	IN
Altitude	msl bound lower : 26000 msl bound upper : 26700
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	artcc : zau.artcc
Operator	common carrier : air carrier
Make Model Name	B727 Undifferentiated or Other Model
Operating Under FAR Part	Part 91
Navigation In Use	other vortac
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : cfi pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 200 flight time total : 21000 flight time type : 5000
ASRS Report	499710
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : instrument pilot : commercial
Events
Anomaly	aircraft equipment problem : less severe altitude deviation : excursion from assigned altitude non adherence : clearance
Independent Detector	other flight crewa other flight crewb
Resolutory Action	flight crew : returned to assigned altitude other
Supplementary
Problem Areas	Flight Crew Human Performance Aircraft
Primary Problem	Aircraft

Narrative:

During a ferry flight to pick up cargo in minneapolis, mn, and return to indianapolis, in, the flight crew engaged the autoplt in cruise at FL260. The autoplt had been written up on previous flts and the maintenance crew in indianapolis asked the flight crew to help troubleshoot the autoplt problem en route if possible. After a short time level at FL260 with the autoplt on, the nose pitched up abruptly and the aircraft climbed to FL267 before the flight crew was able to overpwr the autoplt pitch command and disconnect the autoplt. The crew descended to FL260 and hand flew the aircraft for the rest of the flight.

Original NASA ASRS Text

Title: B727 CREW EXPERIENCED AN ABRUPT NOSE UP PITCH DURING CRUISE.

Narrative: DURING A FERRY FLT TO PICK UP CARGO IN MINNEAPOLIS, MN, AND RETURN TO INDIANAPOLIS, IN, THE FLC ENGAGED THE AUTOPLT IN CRUISE AT FL260. THE AUTOPLT HAD BEEN WRITTEN UP ON PREVIOUS FLTS AND THE MAINT CREW IN INDIANAPOLIS ASKED THE FLC TO HELP TROUBLESHOOT THE AUTOPLT PROB ENRTE IF POSSIBLE. AFTER A SHORT TIME LEVEL AT FL260 WITH THE AUTOPLT ON, THE NOSE PITCHED UP ABRUPTLY AND THE ACFT CLBED TO FL267 BEFORE THE FLC WAS ABLE TO OVERPWR THE AUTOPLT PITCH COMMAND AND DISCONNECT THE AUTOPLT. THE CREW DSNDED TO FL260 AND HAND FLEW THE ACFT FOR THE REST OF THE FLT.

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.