Replace worn out stop lugs to reduce drag? Really?
This often overlooked but important part is affordable at McFarlane!
The torque link stop lug is a sacrificial part that hammers against a flat spot on the lower part of the shock strut outer tube when the strut extends after takeoff. This prevents the strut from overextending and forces the nose wheel and rudder system into proper alignment for flight.
Due to repeated hammering with every takeoff, these stop lugs must be periodically replaced. Excessive wear can allow overextension of the strut. They also often wear unevenly resulting in inconsistent alignment of the nose wheel in flight which then causes extra drag and yaw. The extra yaw can require increased rudder trim which causes even more drag. So yes, replacing a torque link stop lug can reduce drag!
For ordering information, go to Torque Link Stop Lugs and Safety Plate.
Other nose wheel steering parts:
Replace the stop lug if it is no longer flush with the strut, mushroomed, worn, rounded, bent away from the torque link, or if it has stress cracks. The safety plate should not be reused.
|More important than you think
Overextension of the nose strut due to a worn out stop lug can lead to a cascade of problems. McFarlane A&P mechanics have seen struts over extend to the point where the metering pin comes out of the orifice. This results in loss of dampening action and the pin hammering the orifice every landing, and distorting and enlarging it. Over time, the excess nose strut travel and lack of dampening can result in fatigue cracks in the torque link arms. McFarlane recommends thoroughly inspecting all nose strut components when replacing a severely worn stop lug.