A B737-200 at leveloff at 15000 ft experienced an uncommanded right nose rudder input of from 1-2 se...

Attributes
ACN	430945
Time
Date	199903
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : mlu.airport
State Reference	LA
Altitude	msl single value : 15000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zme.artcc
Flight Phase	cruise : level cruise : enroute altitude change
Route In Use	enroute : on vectors
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : multi engine pilot : instrument pilot : flight engineer pilot : atp pilot : commercial
Experience	flight time last 90 days : 131 flight time total : 8851 flight time type : 775
ASRS Report	430945
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial pilot : multi engine
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : rudder position indicator other flight crewa other flight crewb
Resolutory Action	flight crew : regained aircraft control none taken : insufficient time
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

Had just leveled at 15000 ft, heading 080 degrees, on top in clear. Airspeed 330 KIAS, 'a' autoplt engaged since 7000 ft. Aircraft experienced hard nose right or uncommanded right rudder for approximately 1-2 seconds. Rudder pedals remained neutral, yam damper on, remainder of flight uneventful. Situation was written up in logbook as uncommanded rudder. I did not mention yaw damper because it never clicked off, nor did it show any other abnormality. Callback conversation with reporter revealed the following information: the reporter stated the yaw damper did not disconnect when the momentary kick occurred and remained on during the entire flight. The reporter said no follow-up was made with maintenance to determine what corrective actions, if any, were made.

Original NASA ASRS Text

Title: A B737-200 AT LEVELOFF AT 15000 FT EXPERIENCED AN UNCOMMANDED R NOSE RUDDER INPUT OF FROM 1-2 SECONDS DURATION.

Narrative: HAD JUST LEVELED AT 15000 FT, HDG 080 DEGS, ON TOP IN CLR. AIRSPD 330 KIAS, 'A' AUTOPLT ENGAGED SINCE 7000 FT. ACFT EXPERIENCED HARD NOSE R OR UNCOMMANDED R RUDDER FOR APPROX 1-2 SECONDS. RUDDER PEDALS REMAINED NEUTRAL, YAM DAMPER ON, REMAINDER OF FLT UNEVENTFUL. SIT WAS WRITTEN UP IN LOGBOOK AS UNCOMMANDED RUDDER. I DID NOT MENTION YAW DAMPER BECAUSE IT NEVER CLICKED OFF, NOR DID IT SHOW ANY OTHER ABNORMALITY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE YAW DAMPER DID NOT DISCONNECT WHEN THE MOMENTARY KICK OCCURRED AND REMAINED ON DURING THE ENTIRE FLT. THE RPTR SAID NO FOLLOW-UP WAS MADE WITH MAINT TO DETERMINE WHAT CORRECTIVE ACTIONS, IF ANY, WERE MADE.

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.

A B737-200 at leveloff at 15000 ft experienced an uncommanded right nose rudder input of from 1-2 seconds duration.