What is the purpose of an anti-climber on a train?

The primary purpose of an anti-climber is to prevent 'overriding' or 'telescoping' during a collision. It locks the ends of two train cars together vertically, ensuring that the crash energy is absorbed by the frame and crumple zones rather than allowing one car to crush the passenger compartment of another.

How does a railway anti-climber work?

It works by using textured surfaces, such as horizontal ribs or teeth, located on the front of the train chassis or couplers. Upon impact, these surfaces mesh with the opposing vehicle's anti-climber, physically preventing vertical movement while allowing horizontal compression.

What is telescoping in a train crash?

Telescoping is a catastrophic type of train accident where the underframe of one vehicle overrides the underframe of the next, shearing through the upper body shell and effectively sliding inside it. Anti-climbers are specifically designed to prevent this.

Are anti-climbers mandatory on trains?

Yes, in many regions. For example, in the European Union, the EN 15227 standard for crashworthiness requires measures to prevent overriding, which effectively mandates the use of anti-climbing devices on new rolling stock.

The Shield Against Override: How Anti-Climbers Prevent Telescoping

What prevents train cars from stacking during a crash? Discover the vital role of the Anti-Climber, a safety device designed to stop overriding and prevent telescoping.

December 10, 2025 12:37 pm

What is an Anti-Climber?

An Anti-Climber is a passive safety structural feature located at the ends of railway vehicles, typically integrated into the chassis, buffers, or couplers. Its primary function is to prevent one train car from lifting off the tracks and riding up over the adjacent car (a phenomenon known as “overriding”) during a collision. By interlocking with the opposing vehicle, it ensures that crash forces are directed horizontally into the train’s energy absorption systems rather than vertically into the passenger compartment.

The Danger: Telescoping vs. Absorption

Without anti-climbers, a high-speed impact can cause the frame of one carriage to shear through the superstructure of the next—a catastrophic event called telescoping. The anti-climber uses horizontal ribs, teeth, or robust plates that mesh together upon impact. This engagement locks the vertical movement of the vehicles, forcing them to remain aligned so that crumple zones can effectively crush and absorb the kinetic energy.

Design and Standards

Modern rolling stock design is governed by strict crashworthiness standards, such as EN 15227 in Europe. These regulations mandate that trains must resist vertical displacement during a collision. Anti-climbers are the physical implementation of this requirement, ensuring the survival space for passengers and the driver remains intact.

Comparison: Collision Dynamics

The difference between a collision with and without anti-climbing devices is the difference between a repairable incident and a mass-casualty event.

Collision Aspect	Without Anti-Climber	With Anti-Climber
Vertical Movement	Unrestricted; high risk of “ramp” effect.	Restricted; vehicles lock together vertically.
Energy Path	Chaotic; force shears through weak body shells.	Controlled; force directed to chassis/crumple zones.
Primary Risk	Telescoping: One car enters another.	Deceleration: High G-forces (but structure stays intact).
Passenger Survival	Low (due to structural intrusion).	High (survival space preserved).

Types of Anti-Climbers

Anti-climbers appear in various forms depending on the train type:

Ribbed Plates: Horizontally grooved steel plates on the headstock that mesh like a zipper.
Coupler Integration: Modern automatic couplers often feature built-in anti-climbing elements that lock before the main crash tubes deform.
Buffer Interlock: Side buffers designed with specific geometries to prevent slipping over one another.