I recently learned that there is a locking mechanism on the nose wheel of a Robin DR-400. This mechanism locks the nose wheel in place when there is no weight on the wheel. In particular, the wheel will be locked when the plane is in the air. And at landing, when there is weight on the wheel again, it unlocks. But the nose wheel can also become locked if the center of gravity of the plane is too far back, or may fail to unlock upon landing. In this case, the aircraft becomes uncontrollable, and this can cause a runway excursion.
So I am wondering a few things:
- How does this mechanism work?
- What is gained by having the nose wheel lock itself? Rather than for instance a spring-like mechanism that just keep the wheel aligned with the plane when the plane is in the air.
- Are there other planes with a similar locking mechanism?
- Are there planes with a different mechanism to keep the nose wheel from moving in flight?
Here is what the landing gear looks like. It is not retractable and there are fairings on the wheels for better aerodynamics: