Staying on Track: The Essential Guide to EN 14363 and Running Dynamics

What is EN 14363?

EN 14363 is the overarching European Standard titled “Railway applications – Testing for the acceptance of running characteristics of railway vehicles – Testing of running behaviour and stationary tests.” It dictates the procedures required to validate that a train moves safely and smoothly on the track.

Effectively superseding the legacy **UIC 518** leaflet, EN 14363 is the cornerstone of vehicle authorization (homologation) in Europe. It ensures that rolling stock—whether high-speed trains, locomotives, or freight wagons—does not pose a risk of derailment and does not exert excessive forces that could damage the infrastructure.

The Two Pillars of Assessment

The standard divides the acceptance criteria into two distinct categories, both of which must be satisfied during on-track tests:

• Running Safety: This is the absolute critical limit to prevent accidents. It focuses on the risk of derailment (climbing the rail) and track shifting. The primary metric here is the Y/Q limit (Nadal criterion), which measures the ratio of lateral force (Y) to vertical load (Q).
• Track Loading & Ride Characteristics: This focuses on the long-term impact. It limits the forces applied to the track to prevent rapid degradation (fatigue) and assesses the vibrational environment for cargo or passenger comfort.

Testing Zones and Conditions

EN 14363 requires vehicles to be tested under varied conditions to prove their versatility. Tests are conducted in different “Test Zones” defined by curve radii:

Zone 1: Straight track and very large curves.
Zone 2: Large radius curves (typically 600m to infinity).
Zone 3: Small radius curves (250m to 400m).
Zone 4: Very small radius curves (less than 250m), critical for tram and metro networks.

Comparison: Simplified vs. Normal Method

Depending on the novelty of the vehicle design, the standard allows for different testing approaches.