Incident Overview

Description
The Boeing 737-33A was on a stabilised approach to runway 27R atr Paris Charles de Gaulle Airport, France. The aeroplane landed with a ground speed of 129 kt. The crew stated that they felt violent vibrations as soon as the wheels touched down, especially through the rudder pedals. During the landing roll, the recorded lateral load varied with increasing amplitude up to 0.8 g at 90 kt (the lateral load factor then reached the absolute maximum value of 0.41 g) then dropped towards 0.4 g at 80 kt. The aeroplane?s path began to deviate slightly to the right of the runway centreline. The oscillations stopped suddenly when the speed reached 75 kt. The aeroplane?s lateral deviation in relation to the runway centreline reached a maximum of about 10 m to the right, then the aeroplane moved back onto the centreline. The aeroplane left the runway via taxiway Z3 and came to a stop before being towed to the ramp. Significant damage was observed on the right main landing gear, especially on the lower torsion link. Conclusion: The accident was caused by the failure, undetected by the maintenance personnel, to reconnect the right main landing gear shimmy damper hydraulic line to the aeroplane?s hydraulic system. The vibrations caused during landing rollout could not be damped down and weakened the torsion link until it failed suddenly. The following factors contributed to the accident: – Poor resource planning caused overstretching of the personnel?s capacities when unexpected extra work turned up. This generated increased time pressure that led to things being forgotten and approximate execution of the work cards. – The supervisor had worked for an excessive number of hours over a long period of time, which lowered his performance and his aptitude to carry out checks efficiently. – Boeing work card nø32-011-00-02 in force in July 2011 did not specifically mention re-connecting the shimmy damper hydraulic line to the aeroplane?s hydraulic system.
Source of Information
https://bea.aero/en/investigation-reports/notified-events/detail/vibrations-rupture-du-compas-du-train-principal-droit-lors-du-roulement-a-latterrissage/https://bea.aero/en/investigation-reports/notified-events/detail/vibrations-rupture-du-compas-du-train-principal-droit-lors-du-roulement-a-latterrissage/Primary Cause
Inadequate maintenance procedures and resource planning regarding the reconnection of the shimmy damper hydraulic line to the aircraft’s hydraulic system.Inadequate maintenance procedures and resource planning regarding the reconnection of the shimmy damper hydraulic line to the aircraft’s hydraulic system.Share on: