Aviation safety investigations & reports

Boeing Co 737-476, VH-TJY

Investigation number:
Status: Completed
Investigation completed


While on final approach to Brisbane at about 1,000 ft, the crew of the Boeing 737 reported feeling a 'kick' in the rudder pedals accompanied by a minor aircraft yaw oscillation. It was reported that there was no aircraft ahead to cause wake turbulence.

Investigation by the aircraft operator suggested a problem with the rudder power control unit. The aircraft manufacturer recommended that the standby rudder actuator and the standby input rod bearings should also be examined for wear; no wear was evident.

The rudder power control unit had accumulated 3,064 hours since its overhaul by the manufacturer in May 1999. It was removed from the aircraft and forwarded to the USA for examination.

The examination was conducted by the component manufacturer and supervised by the National Transportation Safety Board of the USA on behalf of the Australian Transport Safety Bureau. No discrepancies that may have led to the anomaly in the operation of the rudder power control unit were found. The internal and external components contained no evidence of excessive wear, damage or overtravel and met the manufacturer's standards for in-service units.

In support of the investigation, the National Transportation Safety Board also conducted a performance simulation study based on the actual aircraft configuration data at the time of the incident. The study concluded that the rudder had oscillated.

The investigation was unable to determine why the rudder reportedly oscillated.

General details
Date: 18 April 2000   Investigation status: Completed  
Time: 1400 hours EST    
Location   (show map): Brisbane, Outer Marker    
State: Queensland   Occurrence type: Flight control systems  
Release date: 06 February 2001   Occurrence category: Incident  
Report status: Final   Highest injury level: None  

Aircraft details

Aircraft details
Aircraft manufacturer The Boeing Company  
Aircraft model 737  
Aircraft registration VH-TJY  
Serial number 28151  
Type of operation Air Transport High Capacity  
Damage to aircraft Nil  
Departure point Melbourne, VIC  
Departure time 1208 hours EST  
Destination Brisbane, QLD  
Last update 13 May 2014