What is the closed position of the angle **** on PA5 cars?

The closed position of the angle on PA5 cars being in line with the running rails means that when the angle is in this position, it aligns perfectly with the horizontal plane of the track. This alignment is crucial for ensuring that the train operates smoothly and efficiently during travel. When the angle is in line with the running rails, it helps in minimizing friction and maintaining stability as the train navigates the track.

In train operation and engineering, the correct positioning of components is vital for safety and functionality. Having the angle positioned in line with the rails ensures that the train can maintain its intended course and speed without unnecessary complications. This position is especially significant during straight running and in turns where proper alignment prevents derailment and enhances passenger comfort.

The other options suggest orientations that would not provide the necessary stability or alignment required for safe operation on standard tracks. For instance, being perpendicular to the running rails could imply a blocking position that interferes with normal train operations. Similarly, being opposite to the incoming train direction or at an angle like 45 degrees would create issues in terms of the flow and stability of the train, impacting both safety and performance.