Loss of aircraft control results in ground loop.

Attributes
ACN	115712
Time
Date	198906
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : sac
State Reference	CA
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : personal
Make Model Name	Small Aircraft, High Wing, 1 Eng, Retractable Gear
Flight Phase	landing other
Flight Plan	VFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Experience	flight time last 90 days : 25 flight time total : 550
ASRS Report	115712
Events
Anomaly	aircraft equipment problem : critical non adherence : clearance other anomaly other anomaly other other spatial deviation
Independent Detector	other flight crewa
Resolutory Action	flight crew : declared emergency none taken : unable
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

Pattern entry, pattern, final approach and touchdown normal and unremarkable. During rollout, as nose wheel touched down, or shortly thereafter, airplane swerved into a right ground loop and proceeded across open space. Came to rest on a taxiway. No discernable damage to machine or occupant. Full left pedal and brake were unable to straighten up the airplane. Airplane was towed to a&P for diagnosis. Result: right wheel brake may have been worn enough to cause it to grab. Nose wheel shimmy damper was inoperable due to serious corrosion and pitting of shaft and cylinder. Could have caused the nose wheel to lock into a hard right turn confign. Remedy: realign right wheel brake. Replace shimmy damper ($770.00). Lesson: check the a&P's work very carefully when the 100 hours and/or annual inspections are done.

Original NASA ASRS Text

Title: LOSS OF ACFT CTL RESULTS IN GND LOOP.

Narrative: PATTERN ENTRY, PATTERN, FINAL APCH AND TOUCHDOWN NORMAL AND UNREMARKABLE. DURING ROLLOUT, AS NOSE WHEEL TOUCHED DOWN, OR SHORTLY THEREAFTER, AIRPLANE SWERVED INTO A RIGHT GND LOOP AND PROCEEDED ACROSS OPEN SPACE. CAME TO REST ON A TXWY. NO DISCERNABLE DAMAGE TO MACHINE OR OCCUPANT. FULL LEFT PEDAL AND BRAKE WERE UNABLE TO STRAIGHTEN UP THE AIRPLANE. AIRPLANE WAS TOWED TO A&P FOR DIAGNOSIS. RESULT: RIGHT WHEEL BRAKE MAY HAVE BEEN WORN ENOUGH TO CAUSE IT TO GRAB. NOSE WHEEL SHIMMY DAMPER WAS INOPERABLE DUE TO SERIOUS CORROSION AND PITTING OF SHAFT AND CYLINDER. COULD HAVE CAUSED THE NOSE WHEEL TO LOCK INTO A HARD RIGHT TURN CONFIGN. REMEDY: REALIGN RIGHT WHEEL BRAKE. REPLACE SHIMMY DAMPER ($770.00). LESSON: CHECK THE A&P'S WORK VERY CAREFULLY WHEN THE 100 HOURS AND/OR ANNUAL INSPECTIONS ARE DONE.

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.