Bogie axles
Bogie axles, also known as double axle units or pendulum units, are double axles that are connected on each side via balance beams or leaf springs that are rotatably attached to the vehicle frame. The static axle load of two consecutive wheels then remains the same and is independent of the spring travel.
The advantage of this construction is that the tires maintain contact with the ground even on significant bumps. This is used, for example, in forest vehicles that have to drive over tree stumps or mounds of earth.
On larger aircraft, the main landing gear is also often equipped with bogie axles: with a double ( Airbus A300 , A310 , A330 , A340 , Boeing B747 ) or a triple axle ( A380 , B777 ). With this design, the wheels touch down one after the other when landing.
The name comes from the English word bogie for the bogie in railroad cars.
